JPH11231802A - Projector device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve light use efficiency. SOLUTION: Of the light emitted from a lamp 1, light emitted to a region other than a liquid crystal panel 8 in a vertical direction is deflected, and each micro lens of a micro lens array formed on an incident surface of the liquid crystal panel 8 is deflected. Is provided with a polarizing block 4 that can be incident on the light at a predetermined incident angle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a projector device which forms an image by modulating light from a lamp.

[0002]

2. Description of the Related Art FIG. 9 is a schematic diagram showing an example of a configuration of an optical system of a single-panel type liquid crystal projector using, for example, one liquid crystal panel. The lamp 40 has, for example, an elliptical reflector 40a, and reflects the light emitted from the light emitting unit 40b forward. Although not shown, it is also known to use a lamp having a parabolic reflector, for example, and to arrange a light collecting means such as a condenser lens in front of the lamp to collect light. Light emitted from the lamp 40 (RGB)
Is incident on a field lens 42 via a relay lens system 41. Although not shown, the relay lens system 41 is provided with a condensing grating, and an image passing through the grating is used as a virtual light source and enters the field lens 42.

The field lens 42 is a relay lens system 4
1 can be emitted as parallel light, that is, the relay lens 41 and the field lens 42 form a telecentric system. The light beam emitted as parallel light from the field lens 42 is reflected by the total reflection mirror 4 arranged at an angle of, for example, about 45 ° in the horizontal direction with respect to the light beam.
The light is reflected at 3 and is separated by the color separation unit 44 into RGB colors. The color separation unit 44 includes a dichroic mirror 44R that reflects only red light, a dichroic mirror 44G that reflects only green light, and a dichroic mirror 44B that reflects only blue light. For example, about 45
They are arranged with an angle of about °. The dichroic mirrors 44 (R, G, B) are arranged with a predetermined tilt angle δ so as to diverge and emit in the same direction as a horizontal line of an image formed by a liquid crystal panel described later. Each color light reflected here is emitted at an angle of divergence of 2δ to perform color separation.

[0004] Each color light (R, R,
G and B) are incident on a liquid crystal panel unit 48 including, for example, a polarizing plate 45, a liquid crystal panel 46, and a polarizing plate 47. The liquid crystal panel 46 drives a liquid crystal forming a pixel by a driving signal supplied from a path (not shown), and
The light modulation is performed by controlling the transmission of each color light incident through the reference numeral 5. The light beams of the respective colors RGB modulated by the liquid crystal panel unit 48 are enlarged by the projection lens 49 via the polarizing plate 47 and projected on a screen 50 hung on, for example, a wall. The total reflection mirror 43 is not necessarily required in the illustrated configuration because the total reflection mirror 43 is disposed in consideration of miniaturization of the optical system. Therefore, it is also possible to configure so that the parallel light from the telecentric system is directly incident on the color separation unit 44.

Here, the configuration of the liquid crystal panel 46 and the optical paths of the RGB color lights will be described with reference to the schematic diagrams of FIGS. 10 (a) and 10 (b). As shown in FIG. 10A, a thin film transistor (TFT) for driving liquid crystal is provided on the incident surface of the liquid crystal panel 46, for example, in order to correspond to a high definition panel.
r) A microlens array 62 in which microlenses 62a, 62a, 62a,... is formed in a counter substrate of the substrate, that is, in a stage preceding the liquid crystal unit 61. The RGB light beams condensed by the microlens 62a are light-modulated by the liquid crystal unit 61, and are subjected to black matrixes 63 and 6.
The light is emitted from the pixels P which are the gaps of 3, 63... To form an image. Note that, in this figure, as an example, each color light of RGB that is incident on one micro lens 62a is shown. The distance F indicates the focal length (principal point to focal point) of the micro lens 62a, and the distance d indicates the distance from the principal point of the micro lens 62a to the emission portion of the pixel.

The R light (broken line) separated by the color separation unit 44,
G light (solid line) and B light (dashed line) are 2δ
The light enters the microlens 62a at an angle of?, And is condensed and emitted to the pixel P corresponding to the microlens 62a. FIG. 10 shows the pixel P from the front.
The result is as shown in FIG. That is, a square pixel 64 having a stripe structure and forming a color color by three pixels P corresponding to each of the RGB colors is formed. FIG. 10B shows, for example, three square pixels 64 arranged side by side, and a predetermined number of the square pixels 64 are arranged in the horizontal and vertical directions according to the resolution of the image. Will be. The RGB light can be combined by one square pixel 64 by making each of the separated RGB light beams incident on the liquid crystal panel 46 having such pixels at an incident angle of 2δ, for example. A color image can be formed without providing a color filter on the panel 46.

As described above, by providing the microlens array 62 on the incident side of the liquid crystal panel 46, the light-collecting efficiency can be increased, and the effective aperture ratio due to a decrease in the absorptivity when no color filter is used is reduced. Improvement is achieved. Further, since color synthesis using optical elements such as prisms is not required, for example, using three liquid crystal panels corresponding to each color of RGB, light from a lamp is separated for each color, and then light modulation is performed, and then each color is converted. Compared with a three-panel liquid crystal projector that forms a color image by combining light, it is possible to obtain luminance comparable to that of a three-panel liquid crystal projector.

[0008]

By the way, in order to improve the brightness of an image, it has been considered to effectively use the light output from the lamp 40. Normally, the light emitted from the lamp 40 has two orthogonal polarization planes, and these polarization planes generally have a P-polarized component (hereinafter, referred to as P-wave) and an S-polarized component (hereinafter, S-wave). ). That is, by using the polarization conversion means,
The randomly polarized wave (P wave + S
After separating the P wave and the S wave from the (wave), for example, the S wave is converted into the P wave, and an image is formed using only the P wave, thereby achieving light use efficiency.

For example, in a three-panel type liquid crystal projector,
An integrator for effectively using light (randomly polarized light) output from a lamp and an optical system using polarization conversion means for converting the polarization component of light are known. In the optical system of such a three-panel type liquid crystal projector, since an image is formed by using a combination of light of each color, there is no need to use parallel light.

However, in the single-panel type liquid crystal projector described with reference to FIGS. 9 and 10, the angle of incidence of light in the horizontal direction is restricted in order to suppress the mixing of RGB colors. It is necessary to make each color light accurately enter the pixel P corresponding to each color.
For this reason, the light incident on the color separation unit 44 is required to have a degree of parallelism. For example, an illumination system including the lamp 40, the relay lens system 41, the field lens 42, and the like is designed to emit parallel light. .

However, with respect to the substantially circular irradiation area of the lamp 40, for example, the image forming area of the liquid crystal panel is a rectangle having a 4: 3 aspect ratio corresponding to the display image. Therefore, when the parallel light from the illumination system is directly radiated to the liquid crystal panel unit 46, the light radiated to a portion other than the image forming area (for example, the outer frame of the liquid crystal panel) is not used for image formation and is wasted. Had become something.

FIG. 1 shows the optical path of the parallel light incident on the microlens 62a from the side of the liquid crystal panel 46.
As shown in FIG. As described above, the focal point of the microlens 62a is set to be the emission part of the pixel P, so that the parallel light condensed by the microlens 62a enters the pixel P as indicated by an arrow. Therefore, the imaging range of the pixel P is, for example, near the center of the pixel P, as schematically shown in FIG. That is, the image is not uniformly formed in the pixel P, and the image cannot be efficiently formed with respect to the incident area of the pixel P.

The light not used here does not contribute to the brightness of an image to be formed, but also causes heat to be generated inside the apparatus housing. Therefore, cooling means (such as a large fan) is provided. The need arises. This increases the cost and increases the size of the projector device itself. Further, the area of the emission part such as the polarization conversion means is formed to be equal to the area of a liquid crystal panel, for example.
/ 2 area. In other words, there is a problem that it is difficult for the light from the lamp 40 to efficiently enter the incident portion formed with a smaller area than the liquid crystal panel.

[0014]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention separates at least a lamp and light emitted from the lamp into RGB light beams, and forms each of the RGB light beams. Color separation means for emitting light at a predetermined divergence angle in the plane direction corresponding to the horizontal line of the image to be reproduced, and the RG separated by the color separation means.
B: a condensing unit in which a lens group that condenses each color light in a predetermined direction is formed, and a plurality of pixels that form an image by light-modulating each color light condensed by the condensing unit for each color In the projector device provided with the light modulating means, the light emitted from the lamp is deflected in the vertical direction to light other than the light modulating means, and There is provided a light deflecting unit that can make the light enter the lens group at a predetermined incident angle.

According to the present invention, it is possible to effectively use light that has not been used in the past to extend the imaging range in a pixel. That is, since the light use efficiency is improved,
The brightness of the image can be improved. Further, since unnecessary light can be suppressed, the configuration can be made without using a large-sized cooling unit or the like, so that downsizing and cost reduction can be realized.

[0016]

Embodiments of the present invention will be described below. FIG. 1 is a schematic diagram showing one configuration example of an optical system of a single-panel liquid crystal projector device according to the present embodiment. In this figure,
Lamp 1 (reflector 1a, light emitting unit 1b), relay lens system 2, field lens 3, total reflection mirror 5, color separation unit 6 (dichroic mirrors 6R, 6G, 6B), liquid crystal panel unit 10 (polarizing plates 7, 9, The liquid crystal panel 8), the projection lens 11, and the screen 12 correspond to the lamp 4 shown in FIG.
0 (reflector 40a, light emitting section 40b), relay lens system 41, field lens 42, total reflection mirror 43, color separation section 44, liquid crystal panel section 48 (polarizing plates 45, 47, liquid crystal panel 46), projection lens 49, screen 50 is supported.

In the single-panel type liquid crystal projector of the present embodiment, for example, between the field lens 3 and the total reflection mirror 5, the parallel light made of a transparent member and incident on the upper part and the lower part The deflection block 4 which emits light at a predetermined emission angle is arranged. FIG. 2 is a perspective view illustrating the configuration of the deflection block 4. In this deflection block 4, the incident surface 4a facing the lamp 1 and the like is flat. On the emission surface side, the central portion is a flat portion 4b having substantially the same shape as the image forming area of the liquid crystal panel 8, and inclined portions 4c and 4d having a predetermined inclination are formed above and below the flat portion 4b. I have. The inclined portions 4c, 4
The angle formed by d is set according to the angle of incidence on the pixels of the liquid crystal panel 8 as described later.

FIG. 3 is a view for explaining the optical path of the light emitted at a predetermined emission angle by the deflection block 4. In this figure, as a part of the single-panel type liquid crystal projector device,
Only the lamp 1, the deflection block 4, and the liquid crystal panel 8 are shown,
Optical systems such as a color separation unit and a reflection unit are omitted. Light that enters from the central portion of the incident surface 4a and exits from the plane portion 4b reaches the liquid crystal panel 8 as parallel light as it is. Further, the light incident from above the incident surface 4a and transmitted through the inclined portion 4c is emitted in a state where it is refracted downward by the prism effect in the inclined portion 4c. That is, the light emitted from the inclined portion 4c enters the liquid crystal panel 8 from above at a predetermined incident angle. Similarly, the incident surface 4a
Incident from below, and transmitted through the inclined portion 4d, is emitted while being refracted upward by the prism effect in the inclined portion 4d, and enters the liquid crystal panel 8 from below at a predetermined incident angle. Become. Therefore, in this example, parallel light incident on the deflecting block 4 from, for example, upper, front, and lower directions is refracted by the deflecting block 4, and the liquid crystal panel 8 is viewed from a vertical direction in three directions (upper, front). , From below).

Next, an optical path of light incident on the liquid crystal panel 8 from the three directions by the deflection block 4 and an image forming range by the light will be described. FIG. 4 shows a micro lens forming a micro lens array formed on the liquid crystal panel 8,
FIG. 12 is a schematic diagram showing pixels of a stripe structure forming a square pixel from the side, and the microlens 15a and the pixel 17 correspond to the microlens 62a and the pixel P described in FIG.

Light emitted from the plane portion 4b of the deflection block 4 and incident from the front of the liquid crystal panel 8, ie, from the front of the microlens 15a, is shown as a V center, which is substantially the same as the light described in FIG. The light enters the central portion of the pixel 17 through an equivalent path. Light emitted from the inclined portion 4c and incident from above the microlens 15a is V +
And enters below the pixel 17 due to the lens effect of the microlens 15a. Further, light emitted from the inclined portion 4d and incident from below the microlens 15a is indicated as V−,
The light enters above the pixel 17 by the lens effect 5a.

As described above, when the shape of the pixel 17 is a stripe structure, pixels of the same color are arranged in the vertical direction, so that the angles of the inclined portions 4c and 4d can be set relatively rough. it can.

When the incident angle of each color in the horizontal direction is set to, for example, 2δ, and when the incident angle in the vertical direction is also set to 2δ, the range of image formation in the square pixel 16 is as shown in FIG. As indicated by the circle. The micro lens 15a is moved in three directions (V +, V center,
Light incident from V-) can be imaged in the same pixel 17. That is, more light can be taken into the pixel 17 to expand the imaging range, and the brightness can be increased in principle.

As described above, when the pixel 17 has a stripe structure, pixels of the same color are arranged in the vertical direction, so that the angles of the inclined portions 4c and 4d can be set relatively rough. it can. In the case of the square pixel 16, the opening portion is generally set to an aspect ratio of 3: 1. However, the inclination angles of the inclined portions 4c and 4d are set in consideration of the focal length of the microlens 15a. By setting the incident angle with respect to the microlens 15a, it is possible to arbitrarily set the image forming range in the pixel 17.

Further, according to the present invention, separation of each color light of RGB,
And an illumination system (lamp 1, relay lens system 2, field lens 3) having a high degree of parallelism for the purpose of performing the synthesis with high accuracy. It is formed for the purpose of generating parallel light without distinction of directions. Therefore, since parallel light can be obtained also in the vertical direction, the incident angle with respect to the microlens 15a can be accurately set by using the parallel light.

In the above-described embodiment, an example has been described in which the deflection block 4 is disposed between the field lens 3 and the total reflection mirror 5, but, for example, the deflection block 4 is disposed between the total reflection mirror 5 and the color separation unit 6. You may do it. In this case, since the distance to the liquid crystal panel 10 is different, the inclination angles of the inclined portions 4c and 4d are set so that the incident angle corresponds to the distance.

Hereinafter, a modified example of the deflection block 4 will be described. In the deflection block 20 shown in FIG. 6, portions corresponding to the inclined portions 4c and 4d of the deflection block 4 are formed in a saw-toothed shape such as a Fresnel shape.
c and 20d are formed. The light that enters from the central portion of the incident surface 20a and exits from the flat portion 20b directly reaches the liquid crystal panel portion 10 as parallel light. Further, the light incident from above the incident surface 20a and transmitted through the deflecting unit 20c exits while being refracted downward by the deflecting unit 20c. That is, the light emitted from the deflecting unit 20c enters the liquid crystal panel unit 10 from above at a predetermined incident angle. Similarly, light incident from below the incident surface 20a and transmitted through the deflecting unit 20d is emitted while being refracted upward by the deflecting unit 20d, and
The light enters from below at a predetermined angle of incidence.

The deflection block 3 shown in FIG.
0 is a cylindrical lens 30a, 30a, 3
0a... The light emitted from each lens 30a exits at a predetermined divergence angle, and enters the liquid crystal panel 8 at a predetermined angle. In this case, the incident angle slightly varies depending on the position of each lens 30a, and the image forming range is as shown in FIG. That is, since the light enters the pixel 17 in a diffused state, an approximately elliptical image forming range can be obtained in the pixel 17.

Although not shown, for example, the lamp 1
A mirror that folds light emitted to a position outside the liquid crystal panel 8 inward is disposed at an arbitrary position between the liquid crystal panel unit 10 and the liquid crystal panel unit 10, and the angle of incidence of light incident on the liquid crystal panel 8 is determined by the arrangement angle of the mirror. It can also be set.

[0029]

As described above, according to the present invention, the vertical light emitted from the light source and not used conventionally can be converged on the liquid crystal panel surface by the light deflecting means. This makes it possible to effectively use the light from the light source to widen the image forming range in the pixel, thereby improving the brightness of the image. Further, since unnecessary light can be suppressed, the configuration can be made without using a large-sized cooling unit or the like, so that downsizing and cost reduction can be realized. Further, when the present invention is applied to, for example, a single-panel type liquid crystal projector, there is an advantage that it is possible to realize a configuration comparable to that of, for example, a three-panel type liquid crystal projector in terms of luminance.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration example of an optical system of a single-panel type liquid crystal projector device according to an embodiment of the present invention.

FIG. 2 is a perspective view illustrating a configuration of a deflection block according to the present embodiment.

FIG. 3 is a diagram illustrating an optical path to a liquid crystal panel when the deflection block according to the present embodiment is used.

FIG. 4 is a schematic diagram illustrating an incident angle with respect to a pixel of a liquid crystal panel.

FIG. 5 is a diagram schematically showing an image forming area in a pixel of the liquid crystal panel.

FIG. 6 is a diagram illustrating an optical path to a liquid crystal panel when a deflection block according to a modified example is used.

FIG. 7 is a diagram illustrating an optical path to a liquid crystal panel when a deflection block according to another modification is used.

FIG. 8 is a diagram schematically showing an image forming area in a pixel of a liquid crystal panel when a deflection block according to another modification is used.

FIG. 9 is a diagram illustrating a configuration example of an optical system of a conventional single-panel liquid crystal projector device.

FIG. 10 is a diagram illustrating the configuration of a liquid crystal panel and a light path of RGB light of a conventional single-panel type liquid crystal projector device.

11 is a schematic diagram illustrating an incident angle with respect to a pixel of the liquid crystal panel shown in FIG.

12 is a diagram schematically showing an image forming area in a pixel of the liquid crystal panel shown in FIG.

[Explanation of symbols]

1 lamp, 2 relay lens system, 3 field lens, 4, 20, 30 deflection block, 4a entrance surface, 4b
Flat part, 4c, 4d inclined part, six color separation part, 8 liquid crystal panel, 16 square pixels, 17 pixels

Claims (3)

[Claims] 1. At least a lamp and light emitted from the lamp are separated into RGB light beams, and each of the light beams is separated by a predetermined divergence angle in a plane direction corresponding to a horizontal line of an image to be formed. A color separation unit that emits the light in the color separation unit; a light collection unit in which a lens group that collects the RGB light beams separated in the color separation unit in a predetermined direction is formed; A light modulating means in which a plurality of pixels for forming an image by light modulating each color light for each color are arranged. In the projector device, of the light emitted from the lamp, the light modulation is performed in a vertical direction. By deflecting the light emitted to the area other than the means,
A projector device, comprising: a light deflecting unit that can make the light converging unit enter the lens group at a predetermined incident angle. 2. The projector device according to claim 1, wherein in the light deflecting unit, an incident angle with respect to the lens group is set according to a size of an opening of the pixel. 3. The light deflecting means is formed by a plurality of cylindrical lenses formed with a longitudinal direction corresponding to a plane direction corresponding to the horizontal line, and having the light collecting means as an irradiation area. The projector device according to claim 1, wherein