JPS6232420A - Picture display device - Google Patents

Abstract

PURPOSE:To make a device thin and light-weight by changing the waveguide condition to emit an incident light propagated in a plane optical waveguide and displaying it as a picture. CONSTITUTION:The light which is irradiated from a light source 11 and passes polarizers 19a, 19b... to have the angle of the plane of polarization fixed and is made incident on optical waveguides Fa, Fb... is propagated in optical waveguides Fa, Fb... as it is without being emitted out of them while being totally reflected on boundary faces among a core layer 12 and clad layers 13 and 14. If the magnetic field of a prescribed intensity is given to a Farady rotator 18k in the incidence side of the optical waveguide Fk in this state, the incident light which has the angle of the plane of polarization fixed by the polarizer 19k has the angle of the plane of polarization rotated at a required angle thetam so that the direction of the plane of polarization coincides with the direction of an optional analyzer 16km in an analyzer array group. Then, the condition of total reflection on the boundary face between the core layer 12 and the analyzer 16km, namely, the waveguide condition of the light is changed, and the light is emitted out of the waveguide through the analyzer 16km, and the light emission part of the analyzer 16km is displayed in a spot by lighting.

Description

[Detailed description of the invention] Industrial applications The present invention relates to an image display device using an optical waveguide.

2. Description of the Related Art Various types of image display devices have been known in the past for displaying television broadcast images, computer information, and the like.

For example, a cathode ray tube is widely used, in which an electron beam is emitted from an electron gun onto a fluorescent surface to cause it to emit light and display an image.

Further, as an image display device to replace the cathode ray tube, devices using liquid crystals have been put into practical use.

Problems to be Solved by the Invention However, with conventional cathode ray tubes, the electron beam irradiated from an electron gun is deflected within the cathode ray tube to irradiate every corner of the substantially planar fluorescent surface that forms the screen. Since images are displayed by emitting light, it was necessary to prevent the images from being distorted. Therefore, a sufficient electron beam irradiation distance is required so that image distortion is not noticeable, and there is a limit to how thin and lightweight an image display device using a cathode ray tube method can be made.

Therefore, to solve the above problems (-1), as an image display device that is thinner and lighter, a liquid crystal panel that displays images using all liquid crystals that can control the molecular arrangement state by applying an electric field has been put into practical use. However, there are currently drawbacks in terms of resolution, contrast, responsiveness, viewing angle, etc.

Therefore, the present invention was made to solve the problems in conventional technology, and it is possible to achieve a thinner and lighter product with a simple and simple structure, and also has high resolution, high contrast, and a wide viewing angle. It is an object of the present invention to provide an image display device that has excellent responsiveness and high reliability.

Means for Solving All Problems In order to achieve the above object, the present invention is constructed as follows.

A core Mk made of a material with a relatively high refractive index is sandwiched by a cladding layer made of a material with a relatively low refractive index to form a planar optical waveguide, and locally outside the original gold optical waveguide propagated within this optical waveguide. A device for displaying images by emitting light, in which one of the cladding layers is formed by arranging a plurality of analyzers in a matrix, and the direction of the main axis of the plurality of analyzers and light propagation are determined. The rotation means 14 is arranged so that the individual Vs are different in the direction, and rotates the polarization plane angle of all the lights incident on the optical waveguide. According to the image display device of the present invention, light is incident into the optical waveguide formed by the core layer with the entire polarization plane angle of the light rotated by an arbitrary angle. The incident light does not propagate inside the optical waveguide with the angle rotated.Then, the light whose polarization plane angle has been rotated by an arbitrary angle has its principal axis fully rotated to the same angle corresponding to the polarization plane angle of this light. When the light reaches the position of any one analyzer provided in the optical waveguide, light is emitted through the entire analyzer to the outside of the optical waveguide, and the emitting part emits light. This element has all the characteristics of completely transmitting only angular light, and the details will be explained in Examples.

As described above, the polarization plane angle of the light entering the optical waveguide is controlled, and the light is emitted from an arbitrary analyzer to emit light. Analyzers that emit such light are provided in stripes or in a matrix to form pixels, and an arbitrary pixel is selected by controlling the polarization angle as described above to emit light and display an image. Ru.

Example Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show an image display device according to the present invention, which includes a rectangular flat display panel 10 on which a planar optical waveguide is formed, and a display panel 10 provided on one side of the display panel 10. The light source 11 is generally composed of a light source 11 and a light source 11. Light emitted from the light source 11 enters the optical waveguide from one side of the display panel IO and propagates to the opposite side.

The display panel IO has a core layer 12 made of a material with a relatively high refractive index sandwiched between cladding layers 13 and 14 made of a material with a relatively low refractive index to form a planar optical waveguide. The structure is such that the light propagated inside passes through the entire one cladding layer 14 and is locally emitted to the outside of the optical waveguide.

The core layer 12 includes a plurality of substantially rectangular rod-shaped optical waveguides Fa.

A plurality of Fb, . . . are arranged in parallel to form a planar shape.
, is there. The material for the core layer 12 may be transparent or light-transmissive glass, plastic, or the like.

The cladding layer 13 on the back side of the display panel 10 is the substrate 15 of the display panel 10, and is made relatively thick to supplement the strength of the display panel 10. , the substrate 15 is the core layer 1
It is made of glass, plastic, or the like having a relatively lower refractive index than the refractive index of 2. This substrate 15 does not need to transmit light and may be opaque. Alternatively, a mirror-like reflective thin film may be formed on the interface with the core layer 12.

On the other hand, the cladding layer 14 on the front side of the display panel 1O, which becomes the display surface, is formed of an analyzer plate 17 formed by arranging a plurality of microchip-like analyzers 16 in a stripe or matrix shape. .

The analyzer 16 has a property of transmitting light when the light with the required polarization plane angle corresponding to the direction is incident with respect to the polarization plane of the light. The required number of analyzers 16 are arranged in the light propagation direction for each optical waveguide Fa, Fb, mountain, etc. by shifting continuously or intermittently by any angle in all 16 directions. For example, analyzers 16 aI, 16 a2°, etc. are formed on the plate-shaped analyzer plate 17 on one optical waveguide Fa.
..., 16an are arranged in the light propagation direction, and analyzers 16t)t, 16b,
,..., 16bn are arranged in the optical waveguide direction. In this way, the analyzer plate 17 is formed by arranging a plurality of analyzers 16 in a matrix. Then, in each optical waveguide, an analyzer 16
The azimuths of the principal axes of ... are tilted continuously or intermittently at a constant angle with respect to the light propagation direction.

Furthermore, on the light incident side of the optical waveguides Fa, Fb, . . . , there are Faraday rotators 18 a, 18 b, .
, 19 b, .
fi7 ways and then through the Faraday rotator 18a'i. Faraday rotator 18a, l8b,
. . . rotates the polarization plane angle of the light by an arbitrary angle by immersing the light in a magnetic field of arbitrary strength. The polarization plane angle of the incident light into the optical waveguides Fa, Fb, . . . is controlled by a Faraday rotator 18a.
, 18b, . . . , and this magnetic field is controlled by a drive signal from a ringing circuit. Polarizer 19 a,
l 9 b, ..., Faraday rotator 18
a, 18 b, ...... and optical waveguide Fa,
This is provided to keep the initial polarization plane angle of the incident light incident on Fb constant at all times.
The incident light whose polarization plane angle is made constant through the polarizers 19a, 19b, .
, . . . on the way to the exit port on the other side, its polarization plane angle does not correspond to the orientation of any analyzer in the analyzer array group.

Next, the operation of displaying an image by the image display device of this embodiment with the above configuration will be explained. 1) First, as shown in FIG.
The light incident on the optical waveguides Fa, Fb, . . . through the optical waveguides Fa, Fb, . The optical waveguide Fa is totally reflected at the boundary surface of the optical waveguide Fa.

Fb, . . . are propagated as they are without being released outside the road.

In this state, for example, as shown in FIG.
When a magnetic field of a predetermined strength is applied to the Faraday rotator 18k on the incident side of the analyzer, the polarization plane angle is kept constant by the polarizer 19, and the incident light is It is rotated by a required angle θm to match the orientation of an arbitrary analyzer 16 km. Then, the light whose polarization plane angle has been rotated by θm passes through the core layer 12 and the analyzer 16.
The conditions for total reflection at the interface with 16 km, that is, the waveguide conditions for light, change, and the light is no longer emitted to the outside through the analyzer 16 km. Then, the light emitting portion of the 16 km analyzer is displayed as a spot.

As described above, each Faraday rotator 18a.

When the magnetic field applied to the optical waveguides 18b, . The orientation of the analyzer corresponds to the polarization plane angle of the incident light rotated by a required angle by the application of a magnetic field, and the light is emitted out of the path and emitted from there. Now, for each waveguide, 1~
A plurality of spot-like pixels are formed, and an image is displayed with bright and dark contrast added by a collection of the pixels.

In Example E, an optical switch is provided on the light incidence side of each optical waveguide, and the switching operation of the optical switch causes red light, green light, and blue light to selectively enter the all-optical waveguide. According to the image display device of the present invention, it will be possible to colorize images using the so-called RGB method. As described in detail, according to the image display device of the present invention, the incident light that is propagated entirely through the planar optical waveguide is guided. Since the wave conditions can be completely changed, and in particular, the image can be displayed by emitting light from multiple paths, the device can be made extremely thin and lightweight.

In addition, the light that passes through the detector and is emitted outside the road becomes a spot with a small diameter, and because the image is displayed as a collection, the resolution, contrast, and viewing angle are superior to that of conventional methods. Become something. Furthermore, since there is no need to provide any moving parts or mechanical parts, it has excellent high-speed response and high reliability.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the image display device according to the present invention, Fig. 2 is a side view thereof, Fig. 3 is a side sectional view showing the state of propagation of light, and Fig. 4 is an external view of the propagating light. It is a side sectional view explaining release to. 1O... Display panel, 11... Light source, 12... Core layer, 13.14... Clad layer, 15...
・Substrate, Engineering 6... Analyzer, 18...
Faraday rotator (means for rotating the plane of polarization of light), 19...
...Polarizer, F...Optical waveguide. Figure 1

Claims (1)

[Claims] (1) A planar optical waveguide is formed by sandwiching a core layer made of a material with a relatively high refractive index between cladding layers made of a material with a relatively low refractive index, and light propagated within this optical waveguide is guided. The device displays images by emitting light locally outside the wave path, wherein one of the cladding layers is formed by arranging a plurality of analyzers in a matrix, and the plurality of analyzers are arranged in a matrix. An image characterized in that the orientations of the principal axes are individually set to be different from each other with respect to the light propagation direction, and the light is incident into the optical waveguide through a rotation means for rotating the polarization plane angle of the light. Display device.