JP2012203111A - Stereoscopic image display device - Google Patents

Abstract

The present invention provides a stereoscopic image display device capable of simultaneous left-right viewing without using dedicated glasses, with reduced screen resolution and reduced crosstalk.
A stereoscopic image display device 1 is a condensing lens between a backlight 2 and a liquid crystal display 5 having a first image forming region 21 and a second image forming region 22 each including a plurality of horizontal lines 23. It has a Fresnel lens 3 and a retardation plate 4 of optical means having a first polarizing region 31 and a second polarizing region 32. The frame image displays the right-eye image in the first image forming area 21 and the left-eye image in the second image forming area 22, and the image forming areas are alternately switched or overwritten every frame switching. The backlight 2 applies linearly polarized light or circularly polarized light having different polarization directions from the left and right with the center as the boundary in accordance with the display of the right-eye image or the left-eye image in the first image forming area 21 and the second image forming area 22. Radiate.
[Selection] Figure 1

Description

  The present invention relates to a stereoscopic image display device.

  In recent years, thin televisions using a flat display panel have been actively developed. For example, liquid crystal televisions using a liquid crystal panel have been developed. Then, as one approach for improving the functionality of a thin-screen television, development of a stereoscopic image display device that displays a stereoscopic image is being promoted.

  A number of methods have been proposed for a technique for configuring a stereoscopic image display device using a liquid crystal display composed of a liquid crystal panel. They are a method in which an observer needs special glasses when observing a stereoscopic image as disclosed in Patent Document 1, and a method in which glasses are not required as disclosed in Patent Document 2. Can be classified.

  As a stereoscopic image display method using dedicated glasses, the shutter glasses method is known. This method has the advantage that the resolution is not lowered and the viewing angle of the display in the image display device is widened. However, in this method, in addition to the complexity of using dedicated glasses, the observer obtains a natural image due to the occurrence of flicker that causes the display image to flicker, the decrease in brightness on the display screen, and the time difference between the images displayed on the left and right eyes. There is a problem that it is not possible.

  Patent Document 1 discloses a stereoscopic image display device using a phase difference plate having two different polarization regions so that the polarization axes of incident light are orthogonal to each other as a novel optical means. This stereoscopic image display device includes a liquid crystal display that displays a right-eye image and a left-eye image in different areas, and the above-described retardation plate that is arranged to correspond to the left and right image display areas. 3D images can be obtained by projecting parallax images onto the screen.

  In the stereoscopic image display device described in Patent Document 1, the display position according to the right-eye video signal and the display position according to the left-eye video signal on the display screen are always fixed. Therefore, both the left and right images have a problem that the vertical resolution is halved. Further, when observing from the position of a certain viewing angle with respect to the vertical direction of the stereoscopic display device, a part of the image for the right eye on the liquid crystal display reaches the left eye of the observer through the half-wave plate for the left eye. End up. In other words, there is a new problem that crosstalk occurs depending on the observation position.

JP 2006-284873 A JP-A-10-63199

In recent years, a method that does not require dedicated glasses when observing a stereoscopic image has been actively developed.
As methods that do not require special glasses, for example, a parallax barrier method, a lenticular lens method, a switch backlight method, and the like are known. However, the parallax barrier method and the lenticular lens method have a problem that the resolution of image display is lowered, for example, the horizontal resolution is lowered. The switch backlight type has a problem that flicker, which is image flickering, occurs.

  In addition, a stereoscopic image display apparatus that obtains a stereoscopic image using an optical unit having another configuration has been proposed. For example, Patent Document 2 discloses a stereoscopic image display device that uses a polarizing filter or a Fresnel lens as optical means and does not require special glasses.

  In the stereoscopic image display device described in Patent Document 2, right-eye polarization filter sections and left-eye polarization filter sections whose polarization directions are orthogonal to each other on the front and right sides of a light source disposed on the opposite side of the observer across the liquid crystal display. And are arranged. The mutually orthogonally polarized light beams that have passed through the filter parts are made substantially parallel light by the Fresnel lens, and are irradiated toward the liquid crystal display from the back side. In the liquid crystal display, polarizing filters are disposed on both sides. In each of the polarizing filters, linear polarizing filter line portions orthogonal to each other are alternately arranged for each horizontal line so as to correspond to one horizontal line of the liquid crystal display. At this time, the linearly polarizing filter line portions facing each other on the light source side and the viewer side are set to have polarization directions orthogonal to each other. Then, the liquid crystal panel of the liquid crystal display is configured to alternately display the video information for the right eye and the left eye for each horizontal line in accordance with the light transmission lines of the two polarizing filters.

  That is, the stereoscopic image display device described in Patent Document 2 divides all horizontal lines of a display screen into odd lines and even lines, displays left-eye and right-eye images on the respective lines, and displays them as the new optical lines. The three-dimensional image is displayed by allocating to the left and right eyes of the observer.

  According to this apparatus, an observer can observe a stereoscopic image without dedicated glasses. And even if the position seen by the observer is slightly shifted left and right, the stereoscopic image is not damaged. Furthermore, the phenomenon that the horizontal resolution, which is a problem in the parallax barrier method and the lenticular lens method, is halved can be avoided.

  However, in the stereoscopic image display device using the polarization filter described in Patent Document 2, the display position according to the right-eye video signal and the display position according to the left-eye video signal on the display screen are always fixed. Therefore, both the left and right images have a problem that the vertical resolution is halved.

  Therefore, in a method that does not require dedicated glasses, a conventional stereoscopic image display device is insufficient to reduce flicker and crosstalk while maintaining high brightness on the screen, and to prevent a decrease in resolution. There is a need for a new stereoscopic image display device.

  The present invention has been made in view of these points. That is, an object of the present invention is to provide a high-intensity stereoscopic image display device that eliminates the need for dedicated glasses, reduces flicker and crosstalk, and can simultaneously view left and right images without reducing the screen resolution. It is in.

  Other objects and advantages of the present invention will become apparent from the following description.

Aspects of the present invention include a liquid crystal panel configured by arranging a plurality of horizontal lines in which pixels are arranged in the horizontal direction in the vertical direction, and a liquid crystal display having a pair of polarizing plates sandwiching the liquid crystal panel;
A plurality of polarized light sources that emit polarized light, and a backlight having a row of polarized light sources arranged in a horizontal direction so that the polarization directions of the emitted light are different between the polarized light sources adjacent to the left and right;
A condenser lens and optical means are arranged in this order between the liquid crystal display and the backlight,
A stereoscopic image display device that provides a stereoscopic image to an observer,
In the backlight, a plurality of rows of polarized light sources are arranged in the vertical direction, and between the rows of polarized light sources adjacent in the vertical direction, the polarization direction of the emitted light is different between the polarized light sources adjacent in the vertical direction. Configured,
The condensing lens is configured to make the light from the backlight condensing toward the observer,
The liquid crystal display has a first image forming area and a second image forming area, each of which is composed of a plurality of horizontal lines connected to the liquid crystal panel, and the first image forming area is a right-eye image and a left-eye image. The second image forming area is configured to display one of the images at the same time, and the other image is displayed simultaneously.
The first image forming area and the second image forming area are
(1) Whether the image for the right eye and the image for the left eye are switched every time the frame is switched,
Or
(2) In cases other than (1), when switching frames, the right-eye image and the left-eye image are interchanged and the image displayed in the previous frame is overwritten.
The optical means has a position and a size corresponding to the first image forming area and the second image forming area, the first polarizing area and the second polarizing area are arranged, and the first polarizing area and the second polarizing area are Either one forms a half-wave plate, both form half-wave plates whose slow axes are 45 degrees different from each other, or both are quarter wavelengths whose slow axes are 90 degrees different from each other The present invention relates to a stereoscopic image display device that is configured to form a plate.

  In the aspect of the present invention, it is preferable that the backlight is configured so that lighting is controlled for each column of the polarized light source.

  In the aspect of the present invention, the backlight is preferably configured so that lighting is controlled for each polarized light source.

  In the aspect of the present invention, it is preferable that the column of the polarized light sources of the backlight includes four or more polarized light sources.

  In the aspect of the present invention, the backlight is preferably configured by arranging four or more rows of polarized light sources in the vertical direction.

  In the aspect of the present invention, it is preferable that the backlight is configured so that the entire lighting state is controlled in accordance with the timing at which the right-eye image and the left-eye image are switched.

  In the aspect of the present invention, the polarized light source of the backlight is preferably configured using an LED and a polarizing plate.

  In the aspect of the present invention, it is preferable that a light shielding portion is provided at least at a part of the boundary between the first polarizing region and the second polarizing region of the optical means.

  In the aspect of the present invention, each of the first image forming area and the second image forming area is an image forming area composed of 2 to 60 horizontal lines arranged continuously in the vertical direction of the liquid crystal panel. preferable.

  In the aspect of the present invention, each of the first image forming area and the second image forming area is an image forming area composed of 3 to 30 horizontal lines arranged continuously in the vertical direction of the liquid crystal panel. preferable.

  In the aspect of the present invention, each of the first image forming area and the second image forming area is an image forming area composed of 5 to 15 horizontal lines arranged continuously in the vertical direction of the liquid crystal panel. preferable.

  In the aspect of the present invention, the frame switching in the liquid crystal display is preferably performed at a period of 120 Hz or more.

  In the aspect of the present invention, the frame switching in the liquid crystal display is preferably performed at a cycle of 240 Hz or more.

  According to the present invention, it is possible to provide a stereoscopic image display device with a wide viewing angle that can reduce the flicker and crosstalk without using dedicated glasses and can simultaneously view left and right images without reducing the screen resolution. it can.

It is a typical exploded perspective view explaining the principal part composition of the stereoscopic image display device of a 1st embodiment of the present invention. It is a top view which illustrates typically the optical system of the three-dimensional image display apparatus of 1st Embodiment of this invention. It is a top view explaining the polarization characteristic of the polarizing plate which the backlight of the three-dimensional image display device of a 1st embodiment of the present invention has. It is a typical top view of the liquid crystal panel which comprises the three-dimensional image display apparatus of this Embodiment. It is a typical disassembled perspective view explaining the principal part structure of the three-dimensional image display apparatus of 2nd Embodiment of this invention. It is a typical exploded perspective view explaining the principal part structure of the three-dimensional image display apparatus of 3rd Embodiment of this invention. It is a top view which illustrates typically the optical system of the three-dimensional image display apparatus of 3rd Embodiment of this invention. It is a disassembled perspective view which illustrates typically the structure of the backlight which has a liquid crystal element. (A) is a figure which shows typically an example of the polarization characteristic of the light radiated | emitted from a backlight, (b) shows typically another example of the polarization characteristic of the light radiated | emitted from a backlight. FIG. It is a top view which illustrates typically the backlight which the stereoscopic image display apparatus of 4th Embodiment of this invention has. It is a side view which illustrates typically the optical system of the three-dimensional image display apparatus of 4th Embodiment of this invention.

<Embodiment 1>
The stereoscopic image display device 1 according to the first embodiment of the present invention is configured such that one viewpoint (observation position) suitable for observation of a stereoscopic image is formed.

FIG. 1 is a schematic exploded perspective view for explaining a main configuration of the stereoscopic image display apparatus 1 according to the first embodiment of the present invention.
FIG. 2 is a plan view schematically illustrating the optical system of the stereoscopic image display apparatus 1 according to the first embodiment of the present invention.

As shown in FIGS. 1 and 2, the stereoscopic image display apparatus 1 includes a backlight 2, a Fresnel lens 3 that is a condensing lens, a phase difference plate 4 that is optical means, and a liquid crystal display 5 in this order. Prepare. And the control apparatus 12 which respectively controls the drive of the backlight 2 and the liquid crystal display 5 is provided. These are housed in a housing (not shown). As shown in FIGS. 1 and 2, the observer 50 who observes the stereoscopic image observes the stereoscopic image on the screen from the front side of the liquid crystal display 5.
Hereinafter, a main configuration of the stereoscopic image display apparatus 1 will be described.

The backlight 2 is disposed on the farthest side of the stereoscopic image display device 1 when viewed from the observer 50.
In the three-dimensional image display device 1 according to the first embodiment of the present invention, the backlight 2 is composed of two upper and lower light source rows (first row and second row) extending in the horizontal direction. Each of the upper and lower light source columns is composed of two polarized light sources (a polarized light source 13a and a polarized light source 13b, and a polarized light source 14a and a polarized light source 14b).

That is, of the upper and lower two rows of light source columns constituting the backlight 2, two polarized light sources 13 a and 13 b are arranged on the left and right sides with the center as a boundary. In the second row below the first row, two polarized light sources 14a and 14b are arranged on the left and right sides with the center as a boundary.
The four polarized light sources 13a, 13b, 14a, and 14b can be independently controlled by the control device 12, and the lighting state is controlled for each of the upper and lower light source columns. be able to.

  As shown in FIG. 2, the polarized light sources 13a and 13b are configured by disposing polarizing plates 17a and 17b in front of the light sources 15a and 15b that emit white non-polarized light. Similarly, the polarized light sources 14a and 14b not shown in FIG. 2 are each configured by disposing a polarizing plate in front of a light source that emits white non-polarized light. The polarizing plate has a transmission axis and an absorption axis perpendicular to the transmission axis. For example, when non-polarized light emitted from the light source 15a or the light source 15b of the backlight 2 enters the polarizing plate, light having a polarization axis parallel to the transmission axis direction of the non-polarized light is transmitted and a polarization axis parallel to the absorption axis direction. Block the light. Here, the direction of the polarization axis is the vibration direction of the electric field in the light.

  The polarized light sources 13a, 13b, 14a, and 14b can be configured using, for example, a point light source that emits white non-polarized light. Specifically, the polarized light sources 13a, 13b, 14a, and 14b can be configured using LEDs or the like.

  FIG. 3 is a plan view for explaining the polarization characteristics of the polarizing plates 17a, 17b, 18a, and 18b of the backlight 2. As shown in FIG. In FIG. 3, the arrow on each polarizing plate 17a, 17b, 18a, 18b represents the transmission axis of each polarizing plate 17a, 17b, 18a, 18b.

  In the polarized light source 14a and the polarized light source 14b that constitute the first row of light sources and are arranged on the left and right with the center as a boundary, the polarization directions of the polarizing plates 17a and 17b are orthogonal to each other. For example, as shown in FIGS. 1 and 2, the screen of the stereoscopic image display apparatus 1 can be installed so as to face the observer 50 standing on the horizontal ground. In that case, as shown in FIG. 3, in the polarizing plate 17a, the transmission axis is set in a direction perpendicular to the horizontal direction, and in the polarizing plate 17b, the transmission axis is set in the horizontal direction. In addition, regarding the relationship between the first row and the second row of the light sources, the polarizing plates of the polarized light source that are vertically adjacent between the two rows are set so that their polarization directions are orthogonal to each other. Therefore, as shown in FIG. 3, the transmission axis of the polarizing plate 18a included in the polarized light source 14a is set in the horizontal direction, and the transmission axis of the polarizing plate 18b included in the polarized light source 14b is set in a direction perpendicular to the horizontal direction. Is done.

  As a result, when comparing the case where the first row of light sources is turned on and the case where the second row is turned on, the polarization characteristics of the light emitted from the left and right light sources differ from the center. That is, in the first row of light sources, linearly polarized light in a direction perpendicular to the horizontal direction is emitted from the left side at the center, and linearly polarized light in a direction parallel to the horizontal direction is emitted from the right side. On the other hand, in the second row of light sources, linearly polarized light in a direction parallel to the horizontal direction is emitted from the left side at the center, and linearly polarized light in a direction perpendicular to the horizontal direction is emitted from the right side. In the first column and the second column of the light source, the relationship between the characteristics of the polarized light emitted from the center is the opposite relationship on the left and right.

  As a result, the polarization direction of the linearly polarized light emitted from the four polarized light sources 13a, 13b, 14a, and 14b has a polarization characteristic indicated by an arrow in FIG. That is, as shown in FIG. 1, the polarized light source 13a and the polarized light source 13b emit linearly polarized light whose polarization directions are orthogonal to each other toward the liquid crystal display side. Also from the polarized light source 14a and the polarized light source 14b, linearly polarized light whose polarization directions are orthogonal to each other is emitted toward the liquid crystal display side. The linearly polarized lights emitted from the polarized light source 13a and the polarized light source 14a are orthogonal to each other in polarization direction. The same applies between the polarized light source 13b and the polarized light source 14b.

  In the stereoscopic image display apparatus 1, it is also possible to configure the two polarized light sources constituting the first row of light sources described above from one white non-polarized light source by using a surface light source having an appropriate area. It is. That is, it is possible to configure the first row of light sources by disposing two polarizing plates on the front surface of one light source with the vicinity of the center as a boundary. At this time, in the first row of light sources, the polarization directions of two adjacent polarizing plates are set to be orthogonal to each other.

Similarly, the two polarized light sources constituting the second row of light sources can be composed of one white non-polarized light source and two polarizing plates.
However, it is not preferable to configure four polarized light sources using one non-polarized white light source and four polarizing plates. This is because, as will be described later, it is necessary to be able to control the lighting state at least for each row of light sources.

  Next, a sheet-like Fresnel lens 3 as a condensing lens is disposed between the backlight 2 and the phase difference plate 4 so as to have a predetermined distance from the liquid crystal display 5. The Fresnel lens 3 has a concentric concave and convex lens surface on one side surface. Then, light incident from the central focal point on the back side can be emitted to the front side where the liquid crystal display 5 is placed and condensed toward the eyes of the observer.

As shown in FIG. 1, on the front side of the Fresnel lens 3, a retardation plate 4, which is optical means described later, and a liquid crystal display 5 are sequentially arranged.
The liquid crystal display 5 includes a liquid crystal panel 6 sandwiched between a pair of polarizing plates 7 and 8.

  The polarizing plate 7 is disposed on the backlight 2 side of the liquid crystal panel 6 in the liquid crystal display 5. The polarizing plate 7 has a transmission axis and an absorption axis orthogonal to the transmission axis, like the polarizing plates 17a, 17b, 18a, and 18b described above. Therefore, when the linearly polarized light is emitted from the backlight 2, passes through the phase difference plate 4 and is incident thereon, the linearly polarized light having a polarization axis parallel to the transmission axis direction is transmitted, and the linearly polarized light having a polarization axis parallel to the absorption axis direction is transmitted. Shut off. The direction of the transmission axis in the polarizing plate 7 is a direction perpendicular to the horizontal direction when the observer 50 views the stereoscopic image display device 1 as indicated by an arrow in FIG.

The liquid crystal panel 6 is configured by sandwiching liquid crystal with a substrate such as a glass substrate. An electrode having a desired patterning for pixel formation is provided on the surface of the substrate on which the liquid crystal is sandwiched. The electrode is made of a transparent conductive material such as ITO (Indium Tin Oxide). As the liquid crystal panel 6, for example, a color liquid crystal panel in a TN (Twisted Nematic) mode, an IPS (In-Plane-Switching) mode, or a VA (Vertical Alignment) mode can be used. In any of these, the change in the alignment of the liquid crystal is caused by the application of a voltage. In combination with the action of the polarizing plates 7 and 8 disposed on both surfaces of the liquid crystal panel 6, the amount of transmitted light and the like can be adjusted.
The liquid crystal panel 6 is a component responsible for image formation in the stereoscopic image display device 1 and simultaneously displays a right-eye image and a left-eye image on one screen.

FIG. 4 is a schematic plan view of the liquid crystal panel 6 constituting the stereoscopic image display device 1 of the present embodiment.
As shown in FIG. 4, the liquid crystal panel 6 is configured by arranging a plurality of horizontal lines 23 in which pixels (not shown) are arranged in the horizontal direction in the vertical direction. Hereinafter, the configuration and the image display function will be described.

  As shown in FIG. 1, in the image display portion of the liquid crystal panel 6, a first image forming region 21 and a second image forming region 22 that are partitioned in the horizontal direction are provided. The first image forming area 21 and the second image forming area 22 are areas having substantially the same area as each other, as shown in FIG. In the image display portion of the liquid crystal panel 6, the plurality of first image forming areas 21 and second image forming areas 22 are alternately arranged in the vertical direction.

  As shown in FIG. 4, the first image forming area 21 and the second image forming area 22 of the liquid crystal panel 6 are each composed of a plurality of horizontal lines 23 arranged continuously in the vertical direction. In the liquid crystal panel 6 shown in FIG. 4, the first image forming area 21 and the second image forming area 22 are each composed of three horizontal lines 23 arranged in succession.

  As a result, the first horizontal line to the third horizontal line at the top of the liquid crystal panel 6 are bundled to form the first image forming region 21, and the fourth horizontal line to the sixth horizontal line are formed. The second image forming area 22 is bundled to form a first image forming area 21 from the seventh horizontal line to the ninth horizontal line, and the twelfth line from the tenth horizontal line is formed. The second image forming area 22 is configured by bundling up to the horizontal line. That is, three horizontal lines 23 are sequentially bundled, and a plurality of first image forming areas 21 and second image forming areas 22 are alternately formed on the liquid crystal panel 6.

  At this time, the number of horizontal lines 23 constituting the first image forming area 21 and the second image forming area 22 is not limited to three, and can be constituted by a plurality of lines. For example, the number of horizontal lines 23 constituting the first image forming area 21 and the second image forming area 22 can be set to ten.

  In that case, the first horizontal line to the 10th horizontal line at the top of the liquid crystal panel 6 are bundled to form the first image forming area 21, and the 11th horizontal line to the 20th horizontal line are formed. The second image forming area 22 is bundled to form the first image forming area 21 by bundling from the 21st horizontal line to the 30th horizontal line, and the 40th line from the 31st horizontal line. The second image forming area 22 is configured by bundling up to the horizontal line. That is, ten horizontal lines 23 are sequentially bundled, and a plurality of first image forming areas 21 and second image forming areas 22 are alternately formed in the liquid crystal panel 6.

  As will be described later, the number of horizontal lines 23 constituting the first image forming area 21 and the second image forming area 22 is selected from the viewpoint of reducing crosstalk and widening the viewing angle of the liquid crystal display 5. .

On the liquid crystal panel 6 of the liquid crystal display 5 of the stereoscopic image display device 1, a right-eye image and a left-eye image are displayed in the first image forming area 21 and the second image forming area 22 of one frame image to be displayed, respectively. . Then, according to the following method (1) or (2), the right-eye image and the left-eye image are exchanged between the first image forming area 21 and the second image forming area 22.
(1) The right-eye image and the left-eye image are switched every time the frame is switched.
(2) In cases other than (1), at the time of frame switching, one of the replacement of the right-eye image and the left-eye image and the overwriting of the image displayed in the immediately preceding frame is performed (not replaced) Does not include the case where each keeps the image for the right eye and the image for the left eye).

  Although not shown in FIG. 1, an outer frame is disposed on the periphery of the liquid crystal panel 6, and the first image forming region 21 and the second image forming region 22 in the liquid crystal panel 6 are supported by the outer frame. The

  The polarizing plate 8 is disposed on the viewer side in the liquid crystal display 5. The image light that has passed through the first image forming area 21 and the image light that has passed through the second image forming area 22 are incident on the polarizing plate 8. Of these image lights, light whose polarization axis is parallel to the transmission axis is transmitted, and light whose polarization axis is parallel to the absorption axis (perpendicular to the transmission axis) is blocked. Here, the direction of the transmission axis in the polarizing plate 8 can be a direction parallel to the horizontal direction when the observer views the stereoscopic image display device 1 as indicated by an arrow in FIG.

  As shown in FIG. 1, the phase difference plate 4 that is an optical means is disposed between the Fresnel lens 3 and the liquid crystal display 5. The phase difference plate 4 has a first polarizing region 31 and a second polarizing region 32. The positions and sizes of the first polarizing region 31 and the second polarizing region 32 in the phase difference plate 4 are the positions of the first image forming region 21 and the second image forming region 22 of the liquid crystal panel 6 as shown in FIG. It corresponds to the size.

  As described above, in the liquid crystal panel 6 constituting the stereoscopic image display device 1 of the present embodiment shown in FIG. 4, among all the horizontal lines related to the image display of the liquid crystal panel 6, sequentially from top to bottom. Three horizontal lines 23 are bundled to form one set for convenience. Then, the first image forming region 21 and the second image forming region 22 having the same area are provided so as to correspond to each of the bundled horizontal line groups. Therefore, the positions and sizes of the first polarizing region 31 and the second polarizing region 32 in the retardation plate 4 are a set of three horizontal lines bundled in the liquid crystal panel 6 as shown in FIG. This corresponds to the positions and sizes of the one image forming area 21 and the second image forming area 22.

  Therefore, in the usage state of the stereoscopic image display device 1, when a certain frame image is displayed, the light transmitted through the first polarizing region 31 of the phase plate 4 passes through the polarizing plate 7 and the first of the liquid crystal panel 6. The light enters the image forming area 21. The light transmitted through the second polarizing region 32 of the phase difference plate 4 passes through the polarizing plate 7 and enters the second image forming region 22.

  About the structure of the phase difference plate 4, the 1st polarization area 31 is comprised as members, such as glass and resin which do not have a phase difference substantially, and the 2nd polarization area 32 is made into the polarization direction of the incident linearly polarized light, and Correspondingly, it can be configured as a half-wave plate whose optical axis is 45 degrees from the horizontal direction to the upper right. The retardation plate 4 is configured as a half-wave plate in which the first polarization region 31 is made to correspond to the polarization direction of the incident linearly polarized light, and the slow axis is horizontal or vertical with respect to the horizontal direction. The second polarizing region 32 can be configured as a half-wave plate whose optical axis is 45 degrees from the horizontal direction to the upper right.

  By making the structure of the phase difference plate 4 as described above, the light emitted from the phase difference plate 4 with respect to the incident light that is linearly polarized light is not rotated according to the region of the phase difference plate that is transmitted. Either linearly polarized light or linearly polarized light rotated by 90 degrees of the optical axis is obtained. That is, the light incident on the phase difference plate 4 and emitted from the first polarization region 31 of the phase difference plate 4 becomes linearly polarized light with the optical axis not rotated. On the other hand, the light emitted from the second polarization region 32 is linearly polarized light whose optical axis is rotated by 90 degrees.

  In the stereoscopic image display device 1 according to the present embodiment, the first image forming area 21 and the second image forming area 22 correspond to each one of all the horizontal lines related to the image display of the liquid crystal panel 6. It is also possible to provide. In that case, the first polarizing region 31 and the phase difference plate 4 also correspond to the positions and sizes of the first image forming region 21 and the second image forming region 22 corresponding to the horizontal lines 23 of the liquid crystal panel 6. A second polarizing region 32 is formed.

  Then, for example, an image for the right eye and an image for the left eye are respectively provided in the first image forming area 21 corresponding to the horizontal odd line of the one frame image to be displayed and the second image forming area 22 corresponding to the horizontal even line. Each time the frame is switched, the horizontal lines on which the right-eye image and the left-eye image are displayed are alternately switched, and a frame image in which the right-eye image and the left-eye image are interlaced is displayed. .

However, in that case, the problem of crosstalk becomes significant.
That is, the observer 50 may observe a stereoscopic image on the stereoscopic image display device 1 with a certain viewing angle from the central vertical direction of the liquid crystal display 5 constituting the screen of the stereoscopic image display device 1. Originally, when a certain frame image is displayed, the light transmitted through the first polarizing region 31 of the phase difference plate 4 needs to be incident only on the first image forming region 21 of the liquid crystal panel 6. On the other hand, the light transmitted through the second polarizing region 32 needs to be incident only on the second image forming region 22. On the other hand, when the viewing angle is large, the light transmitted through the first polarizing region 31 of the phase difference plate 4 is incident on the second image forming region 22 of the liquid crystal panel 6 and is transmitted through the second polarizing region 32. Light may enter the first image forming area 21.

This type of crosstalk is caused by the fact that the first polarizing region 31 and the second polarizing region 32 having different phase difference characteristics are provided adjacent to each other in the phase difference plate 4.
That is, crosstalk is likely to occur when the observer 50 observes an image on the screen with a viewing angle that is the vertical direction of the screen of the stereoscopic image display device 1.

  This type of crosstalk occurs in the boundary region between the first polarizing region 31 and the second polarizing region 32 that are adjacent to each other in the retardation plate 4. Therefore, in order to reduce this, it is effective to reduce the boundary region between the first polarizing region 31 and the adjacent second polarizing region 32 in the phase difference plate 4.

  For example, it is assumed that the liquid crystal panel 6 corresponds to the full HD (Full High Definition) specification and has 1080 horizontal lines. In this case, if the first image forming area 21 and the second image forming area 22 are provided so as to correspond to all the horizontal lines as described above, 540 of them are alternately provided. As a result, the retardation plate 4 has 540 first polarizing regions 31 and second polarizing regions each corresponding to the position and size of the first image forming region 21 and the second image forming region 22 of the liquid crystal panel 6. 32. Then, 1079 boundary regions between the first polarizing region 31 and the adjacent second polarizing region 32 are formed.

  When the observer 50 observes the screen of the stereoscopic image display device 1 with a certain viewing angle, crosstalk occurs in each of the boundary regions. The strength of the crosstalk becomes highest when the first image forming area 21 and the second image forming area 22 are provided so as to correspond to all the horizontal lines as described above.

  On the other hand, as illustrated in FIGS. 1 and 2, when the first image forming area 21 and the second image forming area 22 of the liquid crystal panel 6 of the present embodiment are configured by a plurality of horizontal lines 23. Is considered. In that case, in the phase difference plate 4, the first polarizing region 31 and the second polarizing region 32 are formed corresponding to the positions and sizes of the first image forming region 21 and the second image forming region 22 of the liquid crystal panel 6. The As a result, the areas of the first polarizing region 31 and the second polarizing region 32 increase according to the number of horizontal lines 23 that are bundled together. Thus, in the phase difference plate 4, the boundary region between the first polarizing region 31 and the adjacent second polarizing region 32 can be reduced.

  That is, since the boundary region between the first polarization region 31 and the second polarization region 32 that generates crosstalk is reduced, the occurrence of crosstalk is reduced as a whole in the stereoscopic image display apparatus 1. Therefore, crosstalk is suppressed as the number of horizontal lines 23 bundled together to form the first image forming area 21 and the second image forming area 22 of the liquid crystal panel 6 increases. And the observer 50 becomes difficult to feel crosstalk.

Therefore, in the stereoscopic image display device 1 of the present embodiment, crosstalk is reduced, the observable viewing angle is expanded, and the viewing angle characteristics are improved.
From the above, from the viewpoint of reducing crosstalk, the number of horizontal lines 23 bundled together to form the first image forming area 21 and the second image forming area 22 of the liquid crystal panel 6 is larger. Is preferred.

  In order to reduce crosstalk, it is also effective to provide a light shielding portion (not shown) in the boundary region between the first polarizing region 31 and the second polarizing region 32 on the surface of the retardation plate 4 facing the liquid crystal display 5. It is. This light shielding part has a belt-like shape, and is preferably disposed in a boundary region between the first polarizing region 31 and the second polarizing region 32.

  By providing such a light-shielding portion (not shown), light that exits from the first polarizing region 31 of the phase difference plate 4 and enters the first image forming region 21 of the liquid crystal panel is adjacent beyond the boundary. It is possible to absorb and block the light incident on the second image forming area 22. By providing the light shielding portion on the phase difference plate 4, it is possible to make it difficult for crosstalk that occurs in the stereoscopic image display device 1 to occur.

  The light shielding portion (not shown) in the phase difference plate 4 is preferably formed of, for example, a binder resin in which a filler component is dispersed. As the filler component, metal particles and oxides thereof, or pigments and dyes are used. The color tone of the filler component is preferably black with respect to the image light. Binder resins for dispersing or dissolving the pigments and dyes are known resins such as acrylic resins, urethane resins, polyesters, novolac resins, polyimides, epoxy resins, vinyl chloride / vinyl acetate copolymers, nitrocellulose, or combinations thereof. Etc. can be used.

  However, the light shielding portion shields part of the image light that passes through the phase difference plate 4 and the liquid crystal display 5 and reaches the eyes of the observer 50. Although effective in reducing the crosstalk, the screen brightness in the image display of the stereoscopic image display device 1 is lowered. For example, as described above, when the first image forming area 21 and the second image forming area 22 are provided so as to correspond to all the horizontal lines, a strip-shaped light shielding that needs to be formed for each boundary area. The number of parts is maximized. As a result, the decrease in luminance due to the formation of the light shielding portion is significant.

Although the formation of the light shielding portions is effective, it is preferable to configure the phase difference plate 4 so as to reduce the number of the light shielding portions.
Therefore, from the viewpoint of reducing the number of light-shielding portions formed, it is preferable that the number of horizontal lines 23 bundled together to form the first image forming region 21 and the second image forming region 22 is larger. Become.

  However, there is a problem in increasing the number of horizontal lines 23 in one set without limitation. That is, it may cause a problem that a natural image cannot be obtained for the observer.

  From the above, in the stereoscopic image display device 1 of the present embodiment, the first aspect of the liquid crystal panel 6 is from the viewpoint of reducing crosstalk and suppressing reduction in screen luminance and providing a natural stereoscopic image to the viewer 50. It is preferable to select the number of horizontal lines 23 that are bundled together to form one image forming area 21 and second image forming area 22. And it is preferable to form the 1st polarizing region 31 and the 2nd polarizing region 32 of the phase difference plate 4 by the position and magnitude | size corresponding to it.

  As a result of intensive studies, the first image forming area 21 and the second image forming area 22 of the liquid crystal panel 6 are respectively arranged in two to 60 horizontal lines that are continuously arranged in the vertical direction of the liquid crystal panel 6. It was found that an image forming area consisting of 23 is preferable.

  Further, each of the first image forming area 21 and the second image forming area 22 of the liquid crystal panel 6 is an image forming area composed of three to thirty horizontal lines 23 arranged continuously in the vertical direction of the liquid crystal panel 6. It is more preferable that the image forming area is composed of 5 to 15 horizontal lines 23. Of course, it is preferable to form the first polarizing region 31 and the second polarizing region 32 of the phase difference plate 4 at positions and sizes corresponding thereto.

  The main configuration of the stereoscopic image display device 1 of the present embodiment has been described above. Next, a method of forming a stereoscopic image by the stereoscopic image display device 1 of the present embodiment and FIG. 1 and FIG. A method for the observer to observe the stereoscopic image will be described.

  When the observer 50 observes a stereoscopic image with the stereoscopic image display device 1, the observer 50 controls the display device to display a single frame image. At that time, a right-eye image and a left-eye image are simultaneously formed on the liquid crystal display 5. That is, for example, a right-eye image and a left-eye image are formed in the first image forming area 21 and the second image forming area 22 of the liquid crystal display 5 by the action of the polarizing plates 7 and 8 and the liquid crystal panel 5, respectively.

  Corresponding to the formation of the image for the right eye and the image for the left eye on the liquid crystal display 5, the control device 12 controls the linearly polarized light from the two polarized light sources 13a and 13b constituting the first row of light sources. It is injected. The polarization direction of linearly polarized light emitted from the polarized light sources 13a and 13b has a polarization characteristic indicated by an arrow in FIG. That is, as shown in FIG. 1, linearly polarized light whose polarization directions are orthogonal to each other is emitted toward the Fresnel lens 3 and the phase difference plate 4 from the polarized light source 13 a and the polarized light source 13 b arranged side by side.

  As shown in FIG. 2, the light emitted from the polarized light source 13 a of the backlight 2 becomes light directed to a region where the right eye 41 a of the observer 50 is present due to the action of the Fresnel lens 3 described above. When the light passes through the phase difference plate 4 and the liquid crystal display 5, the light enters the viewer's right eye 41 a located at a predetermined observation position. On the other hand, the light emitted from the polarized light source 13b becomes light directed to a region where the left eye 41b of the observer is present by the action of the Fresnel lens 3 described above. When the light passes through the phase difference plate 4 and the liquid crystal display 5, the light enters the left eye 41 b of the observer located at a predetermined observation position.

  At this time, as described above, the light incident on the phase difference plate 4 and emitted from the first polarization region 31 of the phase difference plate 4 becomes linearly polarized light without rotating the optical axis and is emitted from the second polarization region 32. The light becomes linearly polarized light rotated by 90 degrees on the optical axis.

  Therefore, the linearly polarized light having a polarization direction perpendicular to the horizontal direction emitted from the polarized light source 13 a passes through the Fresnel lens 3 and the phase difference plate 4 and irradiates the liquid crystal display 5. The transmission axis of the polarizing plate 7 of the liquid crystal display 5 is set in a direction perpendicular to the horizontal direction. Therefore, out of the light emitted from the phase difference plate 4, the light emitted from the first polarizing region 31 can pass through the polarizing plate 7 and is incident on the first image forming region 21 of the liquid crystal panel 6. On the other hand, the light emitted from the second polarizing region 32 of the phase difference plate 4 is linearly polarized light having a polarization direction parallel to the horizontal direction, and is blocked by the polarizing plate 7 and reaches the liquid crystal panel 6. I can't.

  As described above, the right-eye image is formed in the first image forming area 21 of the liquid crystal display 5, and the left-eye image is formed in the second image forming area 22. Therefore, the light emitted from the first polarizing region 31 of the phase difference plate 4 enters the first image forming region 21 of the liquid crystal display 5, and the light transmitted therethrough is image light for the right eye image (hereinafter “right eye image”). Abbreviated as “image light”) and reaches the right eye 41a of the observer. At this time, the light emitted from the polarization light source 13a and having passed through the second polarization region 32 of the phase difference plate 4 does not reach the right eye 41a of the observer 50 as described above.

Further, linearly polarized light having a polarization direction parallel to the horizontal direction emitted from the polarized light source 13 b passes through the Fresnel lens 3 and the phase difference plate 4 and irradiates the liquid crystal display 5. At this time, the transmission axis of the polarizing plate 7 is set in a direction perpendicular to the horizontal direction. Therefore, the light emitted from the first polarizing region 31 out of the light emitted from the phase difference plate 4 is blocked by the polarizing plate 7 and cannot reach the liquid crystal panel 6.
On the other hand, the light emitted from the second polarization region 32 of the phase difference plate 4 is linearly polarized light having a polarization direction in a direction perpendicular to the horizontal direction, and can pass through the polarizing plate 7. The light enters the second image forming area 22.

  As described above, the right-eye image is formed in the first image forming area 21 of the liquid crystal display 5, and the left-eye image is formed in the second image forming area 22. Therefore, the light emitted from the second polarizing region 32 of the phase difference plate 4 enters the second image forming region 21 of the liquid crystal display 5, and the light transmitted therethrough is the image light of the left eye image (hereinafter referred to as “left eye image”). Abbreviated as “image light”) and reaches the left eye 41b of the observer. At this time, the light emitted from the polarized light source 13b and having passed through the first polarizing region 31 of the phase difference plate 4 does not reach the left eye 41b of the observer 50 as described above.

  Thus, the observer 50 can observe only the right eye image light with the right eye and the left eye only with the left eye image when observing the image of the stereoscopic image display device 1. Therefore, the observer 50 can recognize these right-eye image light and left-eye image light as a stereoscopic image.

  Next, a description will be given of a case where, when the observer 50 observes a stereoscopic image with the stereoscopic image display device 1, the image area is switched as the frame is switched as described above. That is, under the control of the control device 12, the left-eye image is formed in the first image forming area 21 in the liquid crystal display 5 and the right-eye image is formed in the second image forming area 22 in a certain frame. The case will be described.

  In the liquid crystal display 5, when the image area is switched along with the frame switching, the control device 12 controls the polarization light source column used in the backlight 2 to be switched. That is, when the formation area of the right eye image and the left eye image is switched, the light source is switched, and the second column is used instead of the first column of the light source. As a result, linearly polarized light is emitted from the two polarized light sources 14a and 14b constituting the second row.

  The polarization direction of the linearly polarized light emitted from the polarized light sources 14a and 14b has the polarization characteristics indicated by arrows in FIG. 1, and the linearly polarized light whose polarization directions are orthogonal to each other is applied to the Fresnel lens 3 and the phase difference plate 4. It is injected towards.

  As in the case of using the first column of the polarized light source described above, the light emitted from the polarized light source 14a becomes light directed to the region where the right eye 41a of the observer 50 is located by the action of the Fresnel lens 3 described above. When the light passes through the phase difference plate 4 and the liquid crystal display 5, the light enters the viewer's right eye 41 a located at a predetermined observation position. On the other hand, the light emitted from the polarized light source 14b becomes light directed to a region where the left eye 41b of the observer is present by the action of the Fresnel lens 3 described above. When the light passes through the phase difference plate 4 and the liquid crystal display 5, the light enters the left eye 41 b of the observer located at a predetermined observation position.

  At this time, as described above, the light incident on the phase difference plate 4 and emitted from the first polarization region 31 of the phase difference plate 4 becomes linearly polarized light without rotating the optical axis and is emitted from the second polarization region 32. The light becomes linearly polarized light rotated by 90 degrees on the optical axis.

  Therefore, the linearly polarized light in the horizontal direction and the horizontal polarization direction emitted from the polarized light source 14 a passes through the Fresnel lens 3 and the phase difference plate 4 and irradiates the liquid crystal display 5. At this time, the transmission axis of the polarizing plate 7 is set in a direction perpendicular to the horizontal direction. Therefore, the light emitted from the first polarizing region 31 is blocked by the polarizing plate 7 and cannot reach the liquid crystal panel 6. On the other hand, out of the light emitted from the phase difference plate 4, the light emitted from the second polarization region 32 of the phase difference plate 4 is linearly polarized light having a polarization direction in a direction perpendicular to the horizontal direction. And enters the second image forming region 22 of the liquid crystal panel 6.

  As described above, the left-eye image is formed in the first image forming area 21 of the liquid crystal display 5, and the right-eye image is formed in the second image forming area 22. Therefore, the light emitted from the second polarizing region 32 of the phase difference plate 4 enters the second image forming region 22 of the liquid crystal display 5, and the light transmitted there from becomes right-eye image light, which is the right eye of the observer. 41a is reached. At this time, the light emitted from the polarized light source 14a and having passed through the first polarizing region 31 of the phase difference plate 4 does not reach the right eye 41a of the observer 50 as described above.

Further, linearly polarized light having a polarization direction perpendicular to the horizontal direction emitted from the polarized light source 14 b passes through the Fresnel lens 3 and the phase difference plate 4 and irradiates the liquid crystal display 5. At this time, the transmission axis of the polarizing plate 7 is set in a direction perpendicular to the horizontal direction. Therefore, out of the light emitted from the phase difference plate 4, the light emitted from the first polarizing region 31 can pass through the polarizing plate 7 and is incident on the first image forming region 21 of the liquid crystal panel 6.
On the other hand, the light emitted from the second polarizing region 32 of the phase difference plate 4 is linearly polarized light having a polarization direction parallel to the horizontal direction, and is blocked by the polarizing plate 7 and reaches the liquid crystal panel 6. I can't.

  As described above, the left-eye image is formed in the first image forming area 21 of the liquid crystal display 5, and the right-eye image is formed in the second image forming area 22. Therefore, the light emitted from the first polarizing region 31 of the phase difference plate 4 is incident on the first image forming region 21 of the liquid crystal display 5, and the light transmitted there from becomes the left-eye image light, and the left eye of the observer 41b is reached. At this time, the light emitted from the polarized light source 14b and having passed through the second polarization region 32 of the phase difference plate 4 does not reach the left eye 41b of the observer 50 as described above.

  Thus, the observer 50 can observe only the right eye image light with the right eye and the left eye only with the left eye image when observing the image of the stereoscopic image display device 1. Therefore, the observer 50 can recognize these right-eye image light and left-eye image light as a stereoscopic image.

  As described above, the state of change is changed between the light for the left eye and the light for the right eye emitted from the backlight 2 in synchronization with the replacement of the image areas accompanying the switching of the frames on the liquid crystal display 5. It is configured so that it can be switched alternately. By doing so, even if the image areas are switched in which the areas for forming the right-eye image and the left-eye image are switched as the frame is switched in the liquid crystal display 5, the observer 50 receives only the right-eye image light in the right eye. The left eye can only observe the image light for the left eye. Therefore, the observer 50 can always recognize these right-eye image light and left-eye image light as a stereoscopic image.

  Therefore, in the conventional stereoscopic image display device, since the image area for forming the right eye image and the left eye image is fixed, there is a problem that the resolution is lowered, for example, the vertical resolution is halved. The stereoscopic image display device 1 can display at a full resolution with the full performance of the liquid crystal display 5 without reducing the resolution at all.

  In addition, in the conventional stereoscopic image display device, only one of the left and right eye images is always displayed, and there may be a time difference when recognizing a stereoscopic image. Since the display device 1 always displays images of the left and right pictures, it is possible to reduce the fatigue of the viewer. In addition, there is also an effect that the sense of incongruity of stereoscopic vision caused by the shift of the left and right images that occurs in the case of a stereoscopic image that moves vigorously is not caused.

Next, the relationship between the formation of a stereoscopic image and the frame frequency in the stereoscopic image display device 1 of the first embodiment will be described.
The liquid crystal display 5 of the stereoscopic image display device 1 simultaneously forms a right-eye image and a left-eye image on one frame image. That is, a right eye image and a left eye image are formed in the first image forming area 21 and the second image forming area 22 of the liquid crystal panel 6 of the liquid crystal display 5 shown in FIG.

  Then, each time the frame is switched, the image forming areas where the right-eye image and the left-eye image are displayed are alternately switched, and a frame image in which the right-eye image and the left-eye image are alternately arranged can be displayed. It is configured as follows. However, in order to reduce the influence of crosstalk caused by the mixture of the right-eye image and the left-eye image that occurs when switching the frame image, after displaying the right-eye image and the left-eye image simultaneously on one frame image, In the next frame, the image area is not replaced, and control is performed so that the image is overwritten, and the overwritten image can be displayed on the liquid crystal display 5 for at least the next one frame period.

  In that case, the control device 12 can simultaneously control blinking of the entire backlight 2. That is, in a period in which one frame image is displayed, either one of the upper and lower columns of the backlight 2 is turned on, and in the frame in which the image forming areas in which the right-eye image and the left-eye image are displayed are replaced before and after that, Control is performed so that the entire backlight 2 is turned off or the luminance is appropriately reduced. By doing so, it is possible to prevent the observer 50 from detecting the above-described crosstalk based on the replacement of the afterimage and the image area of the right-eye image and the left-eye image.

  As described above, when the right-eye image and the left-eye image are simultaneously displayed on one frame image, when the next frame is not overwritten and is overwritten as it is, the optimum frame frequency is set. Thus, the smoothness of the display image is not lost. In the backlight 2, the blinking of the backlight performed for each frame is detected by the observer 50, and there is no concern that the observer feels flicker due to the blinking.

  Therefore, the frame frequency in the liquid crystal display 5 is preferably set to 120 Hz or higher, for example. By doing so, after the image for the right eye and the image for the left eye are simultaneously displayed on one frame image, the image area is not replaced in the next frame, and the frame frequency corresponds to 60 Hz even when overwriting as it is. A stereoscopic image can be formed, the number of times that the image can be switched is increased, and there is no concern that flicker is felt by the observer 50. Further, the flicker resulting from the blinking of the backlight 2 is not perceived by the observer 50. Therefore, the display image provided by the stereoscopic image display device 1 of the present embodiment is also natural.

  Furthermore, in the stereoscopic image display device 1 of the present embodiment, the frame frequency in the liquid crystal display 5 controlled by the control device 12 can be set to 240 Hz. In that case, the controller 12 displays the right-eye image and the left-eye image simultaneously on one frame image by switching the frames, and then overwrites the image area as it is without replacing the image area in the subsequent three frames. Can be controlled. That is, it is possible to form a stereoscopic image by displaying the overwritten image on the liquid crystal display 5 for a period of three frames following the replacement of the image areas.

  When such control is performed, the backlight 2 is turned off only for 1/240 seconds that is the first one frame period, and then the overwriting image display is performed, and the backlight 2 is displayed for 3/240 seconds that is the three frame period. Can be lit. As a result, the backlight is compared with the pattern in which the display area of the right-eye image and the left-eye image on the liquid crystal display 5 is exchanged and overwritten as it is for each frame, which is enabled by driving at 120 Hz. The period during which is turned off can be reduced. As a result, the brightness of the stereoscopic display image in the stereoscopic image display apparatus 1 can be further improved.

  As described above, by improving the frame frequency of the liquid crystal display 5 such as 120 Hz or 240 Hz, it becomes possible to enjoy natural and high-quality stereoscopic display image display.

<Embodiment 2>
The stereoscopic image display device 61 according to the second embodiment of the present invention is configured such that one viewpoint (observation position) suitable for observation of a stereoscopic image is formed. It becomes another example of the same three-dimensional image display apparatus 1 of 1st Embodiment mentioned above.
Hereinafter, the stereoscopic image display device 61 according to the second embodiment of the present invention will be described with reference to the drawings. The same reference numerals are used for the components common to the above-described stereoscopic image display device 1 according to the first embodiment. I will explain.

  FIG. 5 is a schematic exploded perspective view for explaining a main configuration of a stereoscopic image display device 61 according to the second embodiment of the present invention.

  As shown in FIG. 5, the stereoscopic image display device 61 includes a backlight 62, a Fresnel lens 3 that is a condenser lens, a retardation plate 74 that is an optical unit, and a liquid crystal display 5 in this order. And the control apparatus 12 which respectively controls the drive of the backlight 62 and the liquid crystal display 5 is provided. These are housed in a housing (not shown). As shown in FIG. 1, the observer 80 who observes the stereoscopic image observes the stereoscopic image on the screen from the front side of the liquid crystal display 5.

  The stereoscopic image display device 61 according to the second embodiment is particularly different from the stereoscopic image display device 1 according to the first embodiment described above in the structures of the backlight 62 and the phase difference plate 74. Other main components such as the Fresnel lens 3, the liquid crystal display 5, and the control device 12 have the same structure as the above-described stereoscopic image display device 1 and function in the same manner. Therefore, the description which overlaps about the structure of the principal part is abbreviate | omitted.

  The backlight 62 of the stereoscopic image display device 61 has the same arrangement as that of the stereoscopic image display device 1 described above, and includes four polarized light sources 63a, 63b, 64a, and 64b. These are all polarized light sources that emit circularly polarized light on either the left or right side. These polarized light sources can be configured by, for example, providing a linearly polarizing plate and a quarter wavelength plate on top of a point light source that emits white non-polarized light such as an LED.

  Specifically, for example, a linear polarizing plate whose transmission axis is parallel to the horizontal direction is disposed on each of the four point light sources included in the stereoscopic image display device 61. Then, on the linear polarizing plate, a quarter wavelength plate whose slow axis is 45 degrees in the upper right with respect to the horizontal direction or a quarter wavelength plate whose slow axis is 45 degrees in the upper left with respect to the horizontal direction. By stacking, four polarized light sources 63a, 63b, 64a, 64b can be formed. For example, as shown by arrows in FIG. 5, the four polarized light sources emit a right circularly polarized light, a polarized light source 63b emits a left circularly polarized light, and a polarized light source 64a emits a left circularly polarized light. The polarized light source 64b can be configured to emit right circularly polarized light.

  As shown in FIG. 5, the phase difference plate 74 that is an optical unit of the stereoscopic image display device 61 is disposed between the Fresnel lens 3 and the liquid crystal display 5. The phase difference plate 74 has a first polarizing region 71 and a second polarizing region 72. The positions and sizes of the first polarizing region 71 and the second polarizing region 72 on the phase difference plate 74 correspond to the positions and sizes of the first image forming region 21 and the second image forming region 22 of the liquid crystal panel 6. .

  In the stereoscopic image display device 61, as in the stereoscopic image display device 1 described above, in the liquid crystal panel 6, a plurality of horizontal lines among the all horizontal lines related to image display can be bundled to form one set for convenience. it can. The number of horizontal lines to be set can be, for example, three in a row from the top in the vertical direction. Then, the first image forming area 21 and the second image forming area 22 having the same area are provided so as to correspond to each of the bundled horizontal line sets. In that case, the positions and sizes of the first polarizing region 71 and the second polarizing region 72 in the retardation plate 74 are set to the first image forming region 21 and the second image forming region 22 of the liquid crystal panel 6 as shown in FIG. It corresponds to the position and size of. For example, when the liquid crystal panel 6 has three bundled horizontal lines, the first polarizing region 71 and the second polarizing region 72 can be set to positions and sizes corresponding to the set of the three horizontal lines. .

  Therefore, at the time of displaying one frame image with the stereoscopic image display device 61 in use, the light transmitted through the first polarization region 71 of the phase plate 74 passes through the polarizing plate 7 and the first image of the liquid crystal panel 6. Incident into the formation region 21. The light transmitted through the second polarizing region 72 of the phase difference plate 74 passes through the polarizing plate 7 and enters the second image forming region 22.

  Regarding the structure of the phase difference plate 74, the first polarizing region 71 and the second polarizing region 72 are each composed of a quarter-wave plate whose optical axes are orthogonal to each other. For example, the first polarizing region 31 can be configured by using a quarter wavelength plate whose slow axis is 45 degrees from the horizontal direction to the upper right. In addition, the second polarizing region 32 can be configured by using a quarter wavelength plate whose optical axis is 45 degrees from the horizontal direction to the upper left.

  With the retardation plate 74 having such a structure, the retardation plate 74 can control the polarization characteristics of incident light for each polarization region of the first polarization region and the second polarization region. That is, it is emitted from the backlight 62, and the left circularly polarized light and the right circularly polarized light enter the phase difference plate 74. Then, linearly polarized light parallel to the horizontal direction can be emitted or linearly polarized light perpendicular to the horizontal direction perpendicular to the horizontal direction can be emitted according to the polarization region of the incident retardation plate 74.

  Heretofore, the backlight 62 and the phase difference plate 74 of the stereoscopic image display device 61 of the present embodiment have been mainly described. Other components have the same structure as the stereoscopic image display apparatus 1 of the first embodiment as described above. Next, a method for forming a stereoscopic image by the stereoscopic image display device 61 of the present embodiment and a method for the observer 80 to observe the stereoscopic image will be described with reference to FIG.

  When the observer 80 observes a stereoscopic image of the stereoscopic image display device 61, a right-eye image and a left-eye image are simultaneously formed on the liquid crystal display 5 when one frame image is displayed. That is, for example, a right-eye image and a left-eye image are formed in the first image forming area 21 and the second image forming area 22 of the liquid crystal display 5 by the action of the polarizing plates 7 and 8 and the liquid crystal panel 6, respectively.

  Corresponding to the formation of the image for the right eye and the image for the left eye on the liquid crystal display 5, the control device 12 controls the circularly polarized light from the two polarized light sources 63a and 63b constituting the first row of light sources. It is injected. The circularly polarized light emitted from the polarized light sources 63a and 63b has the polarization characteristics shown in FIG. That is, as schematically shown using arrows in FIG. 5, right circularly polarized light is emitted from the polarized light source 63a, and left circularly polarized light is emitted from the polarized light source 63b.

  As shown in FIG. 5, the light emitted from the polarized light source 63 a of the backlight 62 becomes light directed to a region where the right eye 81 a of the observer 80 is present due to the action of the Fresnel lens 3 described above. When the light passes through the phase difference plate 74 and the liquid crystal display 5, the light enters the observer's right eye 81 a located at a predetermined observation position. On the other hand, the light emitted from the polarized light source 63b becomes light directed to the region where the left eye 81b of the observer is present due to the action of the Fresnel lens 3. When the light passes through the phase difference plate 74 and the liquid crystal display 5, the light enters the left eye 81 b of the observer located at a predetermined observation position.

  At this time, the right-handed circularly polarized light emitted from the polarized light source 63a passes through the Fresnel lens 3 and the phase difference plate 74 and irradiates the liquid crystal display 5 as linearly polarized light perpendicular to the horizontal direction. The transmission axis of the polarizing plate 7 of the liquid crystal display 5 is set in a direction perpendicular to the horizontal direction. Therefore, out of the light emitted from the phase difference plate 74, the light emitted from the first polarizing region 71 can pass through the polarizing plate 7 and is incident on the first image forming region 21 of the liquid crystal panel 6. On the other hand, the light emitted from the second polarization region 72 of the retardation plate 74 passes through the retardation plate 74 and becomes linearly polarized light having a polarization direction parallel to the horizontal direction, and is blocked by the polarizing plate 7. Thus, the liquid crystal panel 6 cannot be reached.

  As described above, the right-eye image is formed in the first image forming area 21 of the liquid crystal display 5, and the left-eye image is formed in the second image forming area 22. Therefore, the light emitted from the first polarizing region 71 of the phase difference plate 74 enters the first image forming region 21 of the liquid crystal display 5, and the light transmitted there from becomes right-eye image light, which is the right eye of the observer. 81a is reached. At this time, the light emitted from the polarization light source 63a and having passed through the second polarization region 32 of the phase difference plate 74 does not reach the right eye 81a of the observer 80 as described above.

Further, the left circularly polarized light emitted from the polarized light source 63b passes through the Fresnel lens 3 and the phase difference plate 74, becomes linearly polarized light parallel to the horizontal direction, and irradiates the liquid crystal display 5. At this time, the transmission axis of the polarizing plate 7 is set in a direction perpendicular to the horizontal direction. Therefore, the light emitted from the first polarization region 71 out of the light emitted from the phase difference plate 74 is blocked by the polarizing plate 7 and cannot reach the liquid crystal panel 6.
On the other hand, the light emitted from the second polarization region 72 of the phase difference plate 74 is linearly polarized light having a polarization direction in a direction perpendicular to the horizontal direction, and can pass through the polarizing plate 7. The light enters the second image forming area 22.

  As described above, the right-eye image is formed in the first image forming area 21 of the liquid crystal display 5, and the left-eye image is formed in the second image forming area 22. Therefore, the light emitted from the second polarizing region 32 of the phase difference plate 4 enters the second image forming region 21 of the liquid crystal display 5, and the light transmitted there from becomes the left-eye image light, which is the left eye of the observer. 81b is reached. At this time, the light emitted from the polarized light source 63b and having passed through the first polarization region 71 of the phase difference plate 74 does not reach the left eye 81b of the observer 80 as described above.

  Thus, the observer 80 can observe only the right eye image light with the right eye and the left eye only with the left eye image when observing the image of the stereoscopic image display device 61. Accordingly, the observer 80 can recognize the right eye image light and the left eye image light as a stereoscopic image.

  Next, a case will be described in which when the observer 80 observes a stereoscopic image with the stereoscopic image display device 61, the image area is switched along with the switching of frames. In that case, a left-eye image is formed in the first image forming area 21 of the liquid crystal display 5, and a right-eye image is formed in the second image forming area 22.

  When such switching of image areas is performed, similarly to the stereoscopic image display device 1 described above, the control device 12 switches the polarized light source to be used. That is, the two polarized light sources 64a and 64b constituting the second row of the light sources of the backlight 62 are used. The polarized light source 64a emits left circularly polarized light, and the polarized light source 64b emits right circularly polarized light.

  Thus, in the backlight 62, the polarization characteristic of the circularly polarized light emitted from the left and right light sources with the center as a boundary has the opposite characteristic to that before the switching in synchronization with the switching of the image area. The right-eye image light formed in the second image forming region 22 of the liquid crystal display 5 is obtained by the characteristics of the backlight 62 and the action of the full-lens 3 and the retardation plate 74 configured as described above. Only reaches 81a. At the same time, the image light for the left eye formed in the first image forming area 21 reaches only the left eye 81b of the observer 80. Therefore, the observer 80 can recognize the right eye image light and the left eye image light as a stereoscopic image.

<Embodiment 3>
The stereoscopic image display apparatus 101 according to the third embodiment of the present invention is configured such that there are a plurality of viewpoints (observation positions) suitable for stereoscopic image observation.
Hereinafter, the stereoscopic image display apparatus 101 according to the third embodiment of the present invention will be described with reference to the drawings. The same reference numerals are used for the components common to the above-described stereoscopic image display apparatus 1 according to the first embodiment. The duplicated explanation is omitted.

  FIG. 6 is a schematic exploded perspective view for explaining a main configuration of a stereoscopic image display apparatus according to the third embodiment of the present invention.

  The stereoscopic image display apparatus 101 according to the third embodiment of the present invention is configured to be provided with a plurality of viewpoints (observation positions) so as to correspond to a plurality of observers. The stereoscopic image display apparatus 101 illustrated in FIG. 6 is configured to correspond to four viewpoints (observation positions) that can correspond to the four observers 150a to 150d. When the observer alone observes the stereoscopic image of the stereoscopic image display device 101, since there are a plurality of viewpoints on the left and right, the stereoscopic image of the stereoscopic image display device 101 is observed from a plurality of left and right positions. be able to. Therefore, it is possible to observe a stereoscopic image with a wide viewing angle on the left and right.

  As shown in FIG. 6, in the stereoscopic image display apparatus 101, the backlight 102 is disposed on the farthest side of the stereoscopic image display apparatus 1 when viewed from the viewers 150 a to 150 d. The backlight 102 is composed of two upper and lower light source rows (first row and second row) extending in the horizontal direction. Each of the upper and lower light source columns is composed of eight polarized light sources (113a to 113h and 114a to 114h).

  Of the two upper and lower light source rows constituting the backlight 102, in the upper first row, two polarized light sources, for example, a polarized light source 113a and a polarized light source 113b are arranged on the left and right with the center as a boundary. It constitutes a set. For the other polarized light sources (113c to 113h), the polarized light source 113c and the polarized light source 113d are arranged on the left and right sides of the center to form one set, and the polarized light source 113e and the polarized light source 113f are located at the center. The polarized light source 113g and the polarized light source 113h are arranged on the left and right with the center as a boundary to constitute one set. These four sets of polarized light sources are arranged in the horizontal direction to form the first row of light sources. Each set of four polarized light sources, each composed of two polarized light sources, corresponds to each of the four viewpoints. That is, a set of four polarized light sources is used as a light source in order to form an image that is incident on the left and right eyes of the observers 150a to 150d at each of the four viewpoints.

  Similarly, also in the lower second row, two polarized light sources, for example, polarized light source 114a and polarized light source 114b are arranged on the left and right with the center as a boundary to form one set. For the other polarized light sources (114c to 114h), the polarized light source 114c and the polarized light source 114d are arranged on the left and right sides of the center to form one set, and the polarized light source 114e and the polarized light source 114f are located at the center. The polarized light source 114g and the polarized light source 114h are arranged on the left and right with the center as a boundary to constitute one set. These four sets of two polarized light sources constituting the first row of light sources respectively correspond to the above four viewpoints. That is, a set of four polarized light sources is used as a light source in order to form an image that is incident on the left and right eyes of the respective observers 150a to 150d at the four viewpoints.

  The 16 polarized light sources 113a to 113h and 114a to 114h can be controlled independently by the control device 12, and the lighting state is controlled for each of the upper and lower light source columns. It can be carried out.

  Each of the polarized light sources 113a to 113h and the polarized light sources 114a to 114h is configured by disposing a polarizing plate in front of a light source that emits white non-polarized light, like the above-described polarized light source 113a.

  The polarized light sources 113a to 113h and the polarized light sources 114a to 114h can be configured using, for example, a point light source that emits white non-polarized light. Specifically, it can be configured using an LED or the like.

  In each pair of polarized light sources that constitute the first row of light sources and are arranged on the left and right sides with the center as a boundary, the polarizing plates included in the polarizing plates are orthogonal to each other. For example, the polarization axis of the polarization light source 113a constituting one set of the polarization light sources is set in the direction perpendicular to the horizontal direction, and the polarization axis of the polarization light source 113b is set in the horizontal direction. The setting state of the polarizing plate is the same in other sets of polarized light sources.

  Further, regarding the relationship between the first column and the second column of the light source, similarly to the backlight 2 of the stereoscopic image display device 1 according to the first embodiment described above, the polarized light source adjacent vertically between the two columns. The polarizing plates are set so that the polarization directions are orthogonal to each other. Therefore, in the second column of the polarized light source, the transmission axis of the polarizing plate included in the polarizing light source 114a is set in the horizontal direction, and the transmission axis of the polarizing plate included in the polarized light source 114b that forms a pair with the polarizing axis is a direction perpendicular to the horizontal direction. Set to The setting state of the polarizing plate is the same in other sets of polarized light sources constituting the second row of polarized light sources.

  As a result, when comparing the case where the first row of light sources is turned on and the case where the second row is turned on, the polarization characteristics of the emitted light are different between the vertically adjacent polarized light sources. For example, when the first column is turned on, when linearly polarized light in a direction perpendicular to the horizontal direction is emitted from a certain polarized light source, the corresponding polarized light source in the second column adjacent to the lower side Linearly polarized light in a parallel direction is emitted. On the other hand, when the first row is turned on, when linearly polarized light in a direction parallel to the horizontal direction is emitted from a certain polarized light source, the corresponding polarized light source in the second row is horizontally adjacent to the lower side. Linearly polarized light in a direction perpendicular to the direction is emitted.

  As a result, the polarization direction of linearly polarized light emitted from, for example, the two polarized light sources 113a and the polarized light sources 114a between the upper and lower light source rows has a polarization characteristic indicated by an arrow in FIG. Thus, linearly polarized light whose polarization directions are orthogonal to each other is emitted toward the liquid crystal display side. Also from the polarized light source 113b and the polarized light source 114b, linearly polarized light whose polarization directions are orthogonal to each other is emitted toward the liquid crystal display side. The same applies to the other polarized light sources (113c to 113h and 114c to 114h).

  In the stereoscopic image display apparatus 101, it is also possible to configure the eight polarized light sources constituting the first row of light sources described above from one white non-polarized light source using a surface light source having an appropriate area. It is. That is, it is possible to configure the first row of light sources by appropriately arranging a plurality of polarizing plates on the front surface of one light source. At this time, in the first row of light sources, the polarization directions of two adjacent polarizing plates are set to be orthogonal to each other.

  Similarly, the eight polarized light sources constituting the second row of light sources can be composed of one white non-polarized light source and eight polarizing plates.

  In the three-dimensional image display device 101 according to the third embodiment of the present invention, when the observers 150a to 150d observe a three-dimensional image, the viewer is controlled by the control device 12 and is displayed on the liquid crystal display 5 when one frame image is displayed. The right-eye image and the left-eye image are formed simultaneously. That is, for example, a right-eye image and a left-eye image are formed in the first image forming area 21 and the second image forming area 22 of the liquid crystal display 5 by the action of the polarizing plates 7 and 8 and the liquid crystal panel 6, respectively.

  Corresponding to the formation of the image for the right eye and the image for the left eye on the liquid crystal display 5, from the eight polarized light sources 113a to 113h constituting the first column of the light source of the backlight 102 controlled by the control device 12, Linearly polarized light having the polarization direction shown in FIG. Then, as shown in FIG. 6, linearly polarized light whose polarization directions are orthogonal to each other is emitted toward the Fresnel lens 3 and the phase difference plate 4.

  FIG. 7 is a plan view schematically illustrating the optical system of the stereoscopic image display apparatus according to the third embodiment of the present invention.

  As shown in FIG. 7, the light emitted from the polarization light source 113a of the backlight 102 becomes light directed to the region where the right eye 141g of the observer 150d is present due to the action of the Fresnel lens 3 described above. Then, due to the action of the phase difference plate 4, the right-eye image light that has passed through the liquid crystal display 5 is incident only on the right eye 141g of the observer 150d located at a predetermined observation position. On the other hand, the light emitted from the polarized light source 113b becomes light directed to a region where the left eye 141h of the observer 150d is located by the action of the Fresnel lens 3 described above. Then, due to the action of the phase difference plate 4, the image light for the left eye that has passed through the liquid crystal display 5 is incident only on the left eye 141 h of the observer 150 d located at a predetermined observation position.

  Similarly, the light emitted from the polarized light source 113c of the backlight 102 becomes light directed to a region where the right eye 141e of the observer 150c is present due to the action of the Fresnel lens 3 described above. Then, due to the action of the phase difference plate 4, the image light for the right eye that has passed through the liquid crystal display 5 is incident only on the right eye 141 e of the observer 150 c located at a predetermined observation position. On the other hand, the light emitted from the polarized light source 113d becomes light directed to the region where the left eye 141f of the observer 150c is located by the action of the Fresnel lens 3 described above. Then, due to the action of the phase difference plate 4, the image light for the left eye that has passed through the liquid crystal display 5 is incident only on the left eye 141 f of the observer 150 c located at a predetermined observation position.

  Similarly, the light emitted from the polarized light source 113e of the backlight 102 becomes light directed to a region where the right eye 141c of the observer 150b is present by the action of the Fresnel lens 3 described above. Then, due to the action of the phase difference plate 4, the right-eye image light that has passed through the liquid crystal display 5 is incident only on the right eye 141 c of the observer 150 b located at a predetermined observation position. On the other hand, the light emitted from the polarized light source 113f becomes light directed to the region where the left eye 141d of the observer 150b is located by the action of the Fresnel lens 3 described above. Then, due to the action of the phase difference plate 4, the image light for the left eye that has passed through the liquid crystal display 5 is incident only on the left eye 141d of the observer 150b located at a predetermined observation position.

  Similarly, the light emitted from the polarized light source 113g of the backlight 102 becomes light directed to a region where the right eye 141a of the observer 150a is present due to the action of the Fresnel lens 3 described above. The right-eye image light that has passed through the liquid crystal display 5 is incident only on the right eye 141a of the observer 150a located at a predetermined observation position by the action of the phase difference plate 4. On the other hand, the light emitted from the polarized light source 113h becomes light directed to a region where the left eye 141b of the observer 150a is present due to the action of the Fresnel lens 3 described above. Then, due to the action of the phase difference plate 4, the image light for the left eye that has passed through the liquid crystal display 5 is incident only on the left eye 141 b of the observer 150 a located at a predetermined observation position.

  Thus, the observers 150a to 150d can observe only the image light for the right eye with the right eye and the image light for the left eye with the left eye when observing the image of the stereoscopic image display apparatus 101. . Therefore, the viewers 150a to 150d can recognize the right-eye image light and the left-eye image light as stereoscopic images.

  In addition, when the observers 150a to 150d observe the stereoscopic image by the stereoscopic image display device 101, the image areas are switched in accordance with the switching of the frames as in the stereoscopic image display device 1 of the first embodiment described above. In this case, similarly, the switching field of the polarized light source constituting the backlight 102 is performed, and the second column of the polarized light source is used. As in the case of using the first row of the polarized light sources described above, the observers 150a to 150d have the right eye with the right eye by the action of the phase difference plate 4 and the like described in the stereoscopic image display device 1 according to the first embodiment. Only the image light for the eye can be observed, and only the image light for the left eye can be observed with the left eye. Therefore, the viewers 150a to 150d can recognize the right-eye image light and the left-eye image light as stereoscopic images.

  Therefore, in the conventional stereoscopic image display device, since the image area for forming the right eye image and the left eye image is fixed, there is a problem that the resolution is lowered, for example, the vertical resolution is halved. The stereoscopic image display apparatus 101 can display at the full resolution with the full performance of the liquid crystal display 5 without reducing the resolution at all. Furthermore, the stereoscopic image display apparatus 101 according to the present embodiment can provide a plurality of viewpoints such as the four viewpoints illustrated in FIGS. 5 and 6. Therefore, the stereoscopic image display apparatus 101 according to the second embodiment has an effect that the visual in the left-right direction is enlarged and the stereoscopic image can be observed from various directions.

In the stereoscopic image display apparatus 101 of the third embodiment, when the first row (113a to 113h) or the second row (114a to 114h) of the light source of the backlight 102 is turned on, it is necessary to turn on all the polarized light sources. There is no.
For example, the stereoscopic image display apparatus 101 is provided with a sensor that detects the position of the observer. When there is only one observer, the observation position (viewpoint) is confirmed by a sensor, and only the polarized light source corresponding to the viewpoint is controlled to be turned on. It is also possible to provide an image.

  Further, as another configuration example of the stereoscopic image display apparatus 101 according to the third embodiment, for example, by using a TN (Twisted Nematic) mode liquid crystal element having 90 degrees of optical rotation, the backlight can be separated from one row of light sources. It is also possible to provide a stereoscopic image display device.

  FIG. 8 is an exploded perspective view schematically illustrating the configuration of a backlight having a liquid crystal element.

  As shown in FIG. 8, the backlight 172 used in another configuration example of the stereoscopic image display apparatus 101 according to the third embodiment includes a single row of light sources 173 a to 173 h extending in the horizontal direction. The row of light sources includes, for example, eight light sources 173a to 173h that emit white non-polarized light. A polarizing plate 174 is disposed on each of the eight light sources 173a to 173h. For example, a polarizing plate 174 having a polarization direction in a direction perpendicular to the horizontal direction is disposed, and the eight light sources 173a to 173h are polarization light sources that emit linearly polarized light in a direction perpendicular to the horizontal direction.

  A liquid crystal element 175 is further disposed on the polarizing plate 174 on the eight light sources 173a to 173h. The liquid crystal element is a liquid crystal element formed by sandwiching a 90 degree twisted nematic liquid crystal between a pair of transparent substrates on the surface of which transparent electrodes such as ITO are formed. This liquid crystal element can change the alignment of the liquid crystal between the substrates by applying a voltage. The liquid crystal element 175 has an optical rotation of 90 degrees when no voltage is applied, and the optical rotation disappears when a voltage is applied.

  Therefore, in the backlight 172 including the light sources 173a to 173h, the polarizing plate 174, and the liquid crystal element 175, the polarization characteristics of the light emitted from each light source can be individually selected depending on whether or not the voltage is applied to the liquid crystal element 175. it can.

  FIG. 9 is a diagram schematically illustrating the polarization characteristics of light emitted from the backlight. FIG. 9A is a diagram schematically illustrating an example of the polarization characteristic of light emitted from the backlight, and FIG. 9B is another example of the polarization characteristic of light emitted from the backlight. It is a figure shown typically.

  As a result, as shown in FIG. 9A, in the backlight 172, the light sources 173a, 173c, 173e, 173g, the polarizing plate 174, and the liquid crystal element 175 radiate linearly polarized light having a polarization direction perpendicular to the horizontal direction. The light sources 173b, 173d, 173f, and 173h, the polarizing plate 174, and the liquid crystal element 175 can emit linearly polarized light in the horizontal direction and the horizontal polarization direction.

  In addition, the liquid crystal element is driven to switch the polarization state of the emitted light, and as shown in FIG. 9B, the light sources 173a, 173c, 173e, 173g, the polarizing plate 174, and the liquid crystal element 175 are Can emit linearly polarized light in the direction parallel to the horizontal direction, and radiate linearly polarized light in the direction perpendicular to the horizontal direction from the light sources 173b, 173d, 173f, 173h, the polarizing plate 174, and the liquid crystal element 175. Can do.

Since the backlight 172 has the above-described configuration, it can control the deflection characteristics of light emitted from each polarized light source in the row of light sources, and the backlight of the stereoscopic image display apparatus 101 of the third embodiment described above. A function similar to 102 can be achieved by a row of light sources in a horizontal direction.
Therefore, in another configuration example of the stereoscopic image display apparatus 101 according to the third embodiment, a backlight 172 is used instead of the backlight 102 and a stereoscopic image is formed in the same manner as the stereoscopic image display apparatus 101 according to the third embodiment. Can do.

In another configuration example of the stereoscopic image display apparatus 101 according to the third embodiment, when the light source row of the backlight 172 is turned on, it is not necessary to turn on all the light sources 173a to 173h.
For example, a sensor for sensing the position of the observer is provided in the stereoscopic image display device. When there is only one observer, the observation position (viewpoint) is confirmed by a sensor, and only the light source corresponding to the viewpoint is turned on, the liquid crystal element is also controlled, and the viewpoint of one observer is It is also possible to provide an optimal stereoscopic image only for that.

  In the backlight 102 of the stereoscopic image display apparatus 101 according to the third embodiment shown in FIG. 6, two polarized light sources 113a and 113b are arranged on the left and right sides of the center in the first row on the upper side. It constitutes one set. For the other polarized light sources (113c to 113h), the polarized light source 113c and the polarized light source 113d are arranged on the left and right sides of the center to form one set, and the polarized light source 113e and the polarized light source 113f are located at the center. The polarized light source 113g and the polarized light source 113h are arranged on the left and right with the center as a boundary to constitute one set.

  On the other hand, in another configuration example of the stereoscopic image display apparatus 101 of the third embodiment, it is not necessary to form a set of light sources so as to correspond. For example, only the light source 173b and the light source 173c may be turned on, and a set of light sources arranged on the left and right with the center as a boundary may be configured. In that case, by controlling the liquid crystal element included, the light emitted from the light sources 173b and 173c can be converted into linearly polarized light with desired characteristics and used for the formation of a stereoscopic image.

  As a result, a sensor for detecting the position of the observer is provided in the stereoscopic image display device, and when the observer moves in the left-right direction, the observation position is confirmed, and the column of the light source corresponding to the position is confirmed. It is possible to select two adjacent light sources that can provide the viewer with the optimal left and right images. Then, by controlling the characteristics of the linearly polarized light emitted from the set of selected light sources, the optimal left-eye image and right-eye image are provided to the observer without providing the left and right reverse images, A stereoscopic image can be observed.

  Further, as still another configuration example of the stereoscopic image display apparatus 101 of the third embodiment, the polarized light sources 113a to 113h and the polarized light sources 114a to 114h are respectively used for the backlight 102 in the stereoscopic image display of the second embodiment described above. Similarly to the polarized light source 63a of the device 61, a polarized light source that emits circularly polarized light can be used. In such a case, the polarization direction of the circularly polarized light radiated in each of the pairs of polarized light sources arranged on the left and right sides of the center of the light source row is configured to be opposite to that of the left circularly polarized light and the right circularly polarized light. To do.

  Further, regarding the relationship between the first column and the second column of the light source, similarly to the backlight 62 of the stereoscopic image display device 61 of the second embodiment described above, the polarization of the polarized light source adjacent vertically between the two columns. The characteristic is configured to be opposite to that of left circularly polarized light and right circularly polarized light.

  As in the retardation plate 74 of the stereoscopic image display device 61 according to the second embodiment shown in FIG. 5 described above, the first polarizing region and the second polarizing region are orthogonal to each other. A retardation plate composed of a / 4 wavelength plate is used. In this manner, in the same manner as the stereoscopic image display device 61 shown in FIG. 5, another example of the stereoscopic image display device 101 of the third embodiment can be configured by combining with other components.

<Embodiment 4>
The stereoscopic image display apparatus 201 according to the fourth embodiment of the present invention is configured such that a plurality of viewpoints (observation positions) suitable for stereoscopic image observation are arranged in the left-right direction and expands the viewing angle in the vertical direction. It is configured as follows.
The stereoscopic image display apparatus 201 according to the fourth embodiment has the same structure as the stereoscopic image display apparatus 101 according to the third embodiment described above, except that the configuration of the backlight 202 is different so as to enlarge the viewing angle in the vertical direction.

  Therefore, the structure of the backlight 202 will be described with reference to the drawings, and then the effect of the stereoscopic image display device 201 will be described. And about the component which is common in the stereoscopic image display apparatus 1 of 1st Embodiment mentioned above and the stereoscopic image display apparatus 101 of 3rd Embodiment, a common code | symbol is used and the overlapping description is abbreviate | omitted.

  FIG. 10 is a plan view schematically illustrating the backlight included in the stereoscopic image display apparatus according to the fourth embodiment of the present invention.

  A stereoscopic image display apparatus 201 according to the fourth embodiment includes, for example, a backlight 202 illustrated in FIG. Therefore, similarly to the stereoscopic image display apparatus 101 of the third embodiment described above, it is configured to correspond to four viewpoints (observation positions) in the left-right direction. Further, when one observer 250 observes a stereoscopic image by the stereoscopic image display device 201 of the fourth embodiment, since there are a plurality of viewpoints on the left and right, the stereoscopic image is observed from a plurality of positions on the left and right. It is possible to observe a stereoscopic image with a wide viewing angle improved in the left-right direction.

  In the stereoscopic image display device 201 according to the fourth embodiment of the present invention, the first image forming area 21 and the second image forming area 22 of the liquid crystal panel 6 of the liquid crystal display 5 are arranged in a row in the vertical direction. The horizontal lines 23 are respectively configured. Also in the phase difference plate 4, a first polarizing region 31 and a second polarizing region 32 are provided so as to correspond to the first image forming region 21 and the second image forming region 22 formed of a plurality of horizontal lines 23. Therefore, it has a wide viewing angle in the vertical direction of the screen.

Therefore, in the stereoscopic image display apparatus 201 according to the fourth embodiment of the present invention, the backlight 202 uses the wide viewing angle on the liquid crystal display 5 and the backlight 202 includes a plurality of light source columns in which the number of polarized light sources is greater than the upper and lower columns. It is possible to have For example, as shown in FIG. 10, it is possible to have eight rows of light sources in the vertical direction. Thus, by providing the backlight 202 with a large number of rows of polarized light sources, the viewing angle in the vertical direction can be expanded in the stereoscopic image display device 201 as will be described later.
Note that the number of rows of light sources arranged in the vertical direction is not limited to the eight rows in the above example, and may be four rows, six rows, or more.

In the stereoscopic image display device 201 according to the fourth embodiment of the present invention, the backlight 202 is the most of the stereoscopic image display device 201 as viewed from the observer, like the stereoscopic image display device 101 according to the third embodiment shown in FIG. Arranged on the back side.
And in the three-dimensional image display apparatus 201 of 4th Embodiment of this invention, as shown in FIG. 10, the backlight 202 is comprised from the row | line | column of eight light sources each extended in a horizontal direction. Specifically, the first light source column 211, the second column 212, the third column 213, the fourth column 214, the fifth column 215, and the sixth column. Column 216, seventh column 217, and eighth column 218. The configurations of these light source columns 211 to 218 are the same as those of the first column and the second column of the light sources of the backlight 102 of the stereoscopic image display apparatus 101 according to the third embodiment described above. That is, each of the light source columns 211 to 218 of the backlight 202 is composed of eight polarized light sources.

  The first column 211, the third column 213, the fifth column 215, and the seventh column 217, which are the light source columns of the backlight 202, are respectively the backlights of the stereoscopic image display apparatus 101 according to the third embodiment. It has the same structure as the first row of 102 light sources. Also, the second column 212, the fourth column 214, the sixth column 216, and the eighth column 218, which are the light source columns of the backlight 202, are respectively the backlights of the stereoscopic image display apparatus 101 according to the third embodiment. It has the same structure as the second row of 102 light sources.

  The 64 polarized light sources constituting the first row of light sources 211 to 218, which are the first row of light sources, can be controlled independently. Therefore, in the backlight 202, the lighting state can be controlled for each of the light source columns 211 to 218.

  In the backlight 202 of the stereoscopic image display apparatus 201 according to the fourth embodiment of the present invention having the above configuration, the four backlights 102 of the stereoscopic image display apparatus 101 according to the third embodiment described above are arranged in the vertical direction. The configuration is the same as that described above. That is, a set of the first column 211 and the second column 212 of the light source of the backlight 202 functions in the same manner as the backlight 102 of the stereoscopic image display apparatus 101 of the third embodiment. Similarly, in the column 213 which is the third column and the column 214 which is the fourth column, the column 215 which is the fifth column and the column 216 which is the sixth column, and the seventh column of the light source of the backlight 202 A set of a certain column 217 and an eighth column 218 functions in the same manner as the backlight 102 of the stereoscopic image display apparatus 101 of the third embodiment.

  In this case, the column 211 as the first column, the column 213 as the third column, the column 215 as the fifth column, and the column 217 as the seventh column of the light source of the backlight 202 are respectively described in the third embodiment. Corresponds to the first column of the light source of the backlight 102 of the stereoscopic image display apparatus 101, and performs the same function. Then, the second column 212, the fourth column 214, the sixth column 216, and the eighth column 218 of the light source of the backlight 202 are respectively in the third embodiment. It corresponds to the second column of the light source of the backlight 102 of a certain stereoscopic image display apparatus 101 and performs the same function.

FIG. 11 is a side view schematically illustrating the optical system of the stereoscopic image display apparatus according to the fourth embodiment of the present invention.
As shown in FIG. 11, in the stereoscopic image display device 201, the viewpoint position of the observer 250 that is optimal for observing a stereoscopic image is the first row of light sources at the top of the backlight 202 in the vertical direction. From the optimal position for the pair of the column 211 and the second column 212 to the optimal position for the group of the second column 217 and the eighth column 218 of the light source at the bottom. become.

  That is, regarding the vertical viewpoint of the stereoscopic image display apparatus 201 shown in FIG. 11, the optimal position for the set of the first row 211 and the second row 212 of the light source at the top of the backlight 202, and the third light source Optimal position for the set of column 213 and fourth column 214, Optimal position for the set of fifth column 215 and sixth column 216 of light source, and Optimal for the set of seventh column 217 and eighth column 218 of light source It has four viewpoints consisting of position. In the backlight 102 of the stereoscopic image display apparatus 101 according to the third embodiment described above, the set of light source columns is a set of a first column and a second column. Therefore, the viewing angle in the vertical direction of the stereoscopic image display device 201 is wider than that of the stereoscopic image display device 101 of the third embodiment.

  As described above, the stereoscopic image display apparatus 201 according to the fourth embodiment can increase the viewing angle in the vertical direction in addition to the visual expansion in the left-right direction, and has an effect that a stereoscopic image can be observed from various directions.

In the stereoscopic image display apparatus 201 according to the fourth embodiment, the column 211 that is the first column of the light source of the backlight 202, the column 213 that is the third column, the column 215 that is the fifth column, and the column that is the seventh column. When 217 is lit, it is not necessary to light all the columns simultaneously. Similarly, when the column 212, which is the second column of light sources, the column 214, which is the fourth column, the column 216, which is the sixth column, and the column 218, which is the eighth column, are lit, all the columns of the light sources need to be lit. There is no.
For example, the stereoscopic image display device 201 is provided with a sensor that detects the position of the observer. When there is only one observer, the observation position (viewpoint) is confirmed by a sensor, and only the polarized light source corresponding to the viewpoint is controlled to be turned on. It is also possible to provide an image.

  Further, as another configuration example of the stereoscopic image display device 201 of the fourth embodiment, each polarization light source of the backlight 202 is a circle like the polarization light source 63a of the stereoscopic image display device 61 of the second embodiment described above. A polarized light source that emits polarized light may be used. In that case, in each of the eight rows of light sources, the polarization direction of the circularly polarized light emitted from each pair of the polarized light sources arranged on the left and right with the center as the boundary is opposite to that of the left circularly polarized light and the right circularly polarized light. Configure.

  The relationship between the columns adjacent to the upper and lower sides of the light source is the same as the backlight 62 of the stereoscopic image display device 61 of the second embodiment described above, and the polarization characteristics of the polarized light source adjacent to the upper and lower sides between the two columns are as follows. The left and right circularly polarized lights are configured to be opposite to the left and right circularly polarized lights.

  As in the retardation plate 74 of the stereoscopic image display device 61 according to the second embodiment shown in FIG. 5 described above, the first polarizing region and the second polarizing region are orthogonal to each other. A retardation plate composed of a / 4 wavelength plate is used. In this manner, in the same manner as the stereoscopic image display device 61 shown in FIG. 5, it is possible to configure still another example of the stereoscopic image display device 201 of the fourth embodiment by combining with other components.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

1, 61, 101, 201 Stereoscopic image display device 2, 62, 102, 172, 202 Backlight 3 Fresnel lens 4, 74 Phase difference plate 5 Liquid crystal display 6 Liquid crystal panel 7, 8, 17a, 17b, 18a, 18b, 174 Polarizer 12 Controller 13a, 13b, 14a, 14b, 63a, 63b, 64a, 64b, 113a, 113b, 113c, 113d, 113e, 113f, 113g, 113h, 114a, 114b, 114c, 114d, 114e, 114f, 114g , 114h Polarized light source 15a, 15b, 173a, 173b, 173c, 173d, 173e, 173f, 173g, 173h Light source 21 First image forming area 22 Second image forming area 23 Horizontal line 31, 71 First polarizing area 32, 72 First Two polarization regions 41a, 8 a, 141a, 141c, 141e, 141g Right eye 41b, 81b, 141b, 141d, 141f, 141h Left eye 50, 80, 150a, 150b, 150c, 150d, 250 Observer 175 Liquid crystal element 211, 212, 213, 214, 215, 216, 217, 218 Row of light sources

Claims (13)

A liquid crystal display having a pair of polarizing plates sandwiching the liquid crystal panel, and a liquid crystal panel configured by arranging a plurality of horizontal lines in the vertical direction by arranging pixels in the horizontal direction;
A plurality of polarized light sources that emit polarized light, and a backlight having a row of polarized light sources arranged in a horizontal direction so that the polarization directions of the emitted light are different between the polarized light sources adjacent to the left and right ,
A condensing lens and optical means are arranged in this order between the liquid crystal display and the backlight,
A stereoscopic image display device that provides a stereoscopic image to an observer,
The backlight includes a plurality of columns of the polarized light sources arranged in the vertical direction, and the polarization direction of the emitted light is between the polarized light sources adjacent in the vertical direction between the columns of the polarized light sources adjacent in the vertical direction. Configured to be different from each other,
The condensing lens is configured to collect light from the backlight toward the observer.
The liquid crystal display has a first image forming area and a second image forming area formed by alternately arranging the plurality of horizontal lines of the liquid crystal panel, and the first image forming area is for the right eye. One of the image and the image for the left eye, and the second image forming area is configured to simultaneously display the other image,
The first image forming area and the second image forming area are:
(1) Whether the image for the right eye and the image for the left eye are switched every time the frame is switched,
Or
(2) In cases other than (1), when switching frames, the right-eye image and the left-eye image are interchanged and the image displayed in the previous frame is overwritten.
The optical means includes a first polarizing region and a second polarizing region at positions and sizes corresponding to the first image forming region and the second image forming region, and the first polarizing region and the first polarizing region. Either one of the two polarization regions forms a half-wave plate, or both form half-wave plates whose slow axes are 45 degrees different from each other, or both have the slow axes of 90 degrees each other. A three-dimensional image display device, which is configured to form different quarter-wave plates.   The stereoscopic image display device according to claim 1, wherein the backlight is configured to be controlled to be lit for each column of the polarized light sources.   The stereoscopic image display device according to claim 1, wherein the backlight is configured to be controlled to be turned on for each polarized light source.   The stereoscopic image display device according to claim 1, wherein the row of the polarized light sources of the backlight includes four or more polarized light sources.   5. The stereoscopic image display device according to claim 1, wherein the backlight is configured by arranging four or more rows of the polarized light sources in the vertical direction.   The said backlight is comprised so that the whole lighting state may be controlled according to the timing which replaces the said image for right eyes, and the said image for left eyes, The any one of Claims 1-5 characterized by the above-mentioned. The stereoscopic image display device according to item.   The stereoscopic image display apparatus according to claim 1, wherein the polarized light source of the backlight is configured using an LED and a polarizing plate.   The three-dimensional object according to any one of claims 1 to 7, wherein a light-shielding portion is provided at least at a part of a boundary between the first polarizing region and the second polarizing region of the optical means. Image display device.   Each of the first image forming area and the second image forming area is an image forming area composed of 2 to 60 horizontal lines arranged continuously in the vertical direction of the liquid crystal panel. The three-dimensional image display apparatus of any one of Claims 1-8.   Each of the first image forming area and the second image forming area is an image forming area composed of 3 to 30 horizontal lines arranged continuously in the vertical direction of the liquid crystal panel. The stereoscopic image display apparatus according to claim 9.   Each of the first image forming area and the second image forming area is an image forming area composed of 5 to 15 horizontal lines arranged continuously in the vertical direction of the liquid crystal panel. The stereoscopic image display apparatus according to claim 9.   The stereoscopic image display device according to any one of claims 1 to 11, wherein the frame switching in the liquid crystal display is performed at a cycle of 120 Hz or more.   The stereoscopic image display device according to claim 12, wherein the frame switching in the liquid crystal display is performed at a cycle of 240 Hz or more.

Images