JPH0731332B2 - Flat panel display - Google Patents

Description

The present invention relates to a flat panel display device that leaks light to perform various displays.

(Prior Art) In general, a device utilizing liquid crystal, electroluminescence, electrochromic, fluorescent tube or plasma is used to perform various displays. However, the liquid crystal display device cannot display in a dark place, and the screen is not clear and the response speed is slow. The electroluminescence display device has a dark screen and the electrochromic display device has a slow response speed. In addition, the fluorescent tube type display device has a drawback that it is difficult to produce color, and the plasma type display device has difficulty in producing an intermediate color and has a complicated structure.

(Object of the Invention) An object of the present invention is to provide a simple flat display device having a quick response speed, a clear image, easy colorization and high reliability.

(Structure of the Invention) The flat panel display device of the present invention has N optical waveguides arranged in parallel with each other and having an electro-optical effect, and a matrix form on the optical waveguides so as to intersect the optical waveguides. M upper electrodes arranged side by side in parallel with each other and on the side opposite to the upper electrode with the optical waveguide interposed therebetween, the upper electrodes are arranged in parallel with the upper electrodes, and the upper electrodes are shifted forward and backward with respect to the traveling direction of light. And M lower electrodes to which a voltage is selectively applied so as to generate an electric field in the optical waveguide between the upper electrodes and the upper electrodes, and the M upper and lower electrodes are respectively P widthwise. It is divided to have an interference filter function, and a voltage is applied between the upper and lower electrodes to leak light in the optical waveguide by the interference filter function near the intersection of the upper electrode and the optical waveguide. There is.

By doing so, light is partially leaked from the low-loss optical waveguide for display, so that the screen is clear, the response speed is fast, and colorization is easy by introducing three colors of light into the optical waveguide. By changing the brightness of the light source, intermediate colors can be easily obtained. Also, since this device has an interference filter function by dividing the upper and lower electrodes facing each other, the reflected light is increased and a large amount of light is obtained.

Embodiment An embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 and FIG. 2 show a flat panel display device 10 according to the present invention.
This flat display device 10 is arranged in parallel with each other, and is formed into a matrix form so as to intersect with the N optical waveguides 12 of low loss composed of a core 12a and a clad 12b having an electro-optical effect and the optical waveguides 12. The upper transparent electrodes 14 and the M upper transparent electrodes 14 arranged in parallel to each other are sandwiched between the upper transparent electrodes 14 and are arranged parallel to the upper transparent electrodes 14 on the side opposite to the upper transparent electrodes 14. A device main body 18 including M lower electrodes 16 to which a voltage is applied so as to generate an electric field in the waveguide 12 and a voltage source (not shown) for applying a voltage between the upper and lower electrodes 14 and 16 is provided. ing. The lower electrode 16 is
As shown in FIG. 1, the upper transparent electrode 14 and the opposing upper transparent electrode 14 are arranged so as to be shifted forward and backward with respect to the traveling direction of light.
The device body 18 is mounted on a substrate 20, and an antireflection film 22 is provided on the entire surface. The upper transparent electrode 14 and the lower electrode 16 which face each other are divided into P pieces in the width direction as shown in the figure to have an interference filter function. The number of divisions is an integer, and the distance d must be an odd multiple of λ / 4.

Next, the operation of the device of the present invention will be described with reference to FIG.
When light is incident on a specific optical waveguide, for example, i, from a light source 24 that emits light with high brightness, for example, laser light or LED light, and is applied between a specific upper transparent electrode j and lower electrode 16, the optical waveguide i and the upper electrode An electric field is generated at the intersection with the transparent electrode j,
The refractive index of the divided parts j1, j2, j3 ----- jp of this upper transparent electrode j and the refractive index of j1 and j2, j2 and j3 ----- jp-1 and jp are changed alternately. It constitutes a multilayer film filter. Therefore, the light wave having the wavelength λ is reflected in the upper direction, and the pixels of the matrix i · j which are one element of the image are obtained.

In this case, the wavelength λ can be colored by selecting three colors of red, blue and green. This colorization can be performed by either arranging the three colors in the longitudinal direction of the optical waveguide 12 or by arranging the three kinds of optical waveguides in parallel. However, in the former case, the light source is required to be white light.

As shown in FIG. 1, since the lower electrode 16 and the upper electrode 14 are arranged to be shifted forward and backward with respect to the traveling direction of light, the lines connecting the opposing upper electrode 14 and lower electrode 16 respectively. Means that the light is inclined at an angle θ (see FIG. 1: 0 ° <θ <90 °) with respect to the traveling direction of light. Therefore,
When light is incident on a specific optical waveguide i and a voltage is applied to the upper and lower electrodes, the refractive index changes at an angle θ, and exhibits birefringence characteristics. Therefore, the light is scattered in the vertical direction and the matrix i
j pixels are obtained.

The light introduced into the optical waveguide may be ultraviolet light in addition to visible light. In this case, a fluorescent substance is applied to the surface of the electrode. Further, it is preferable to change the emission efficiency and the emission area so that the amount of light emitted from the optical waveguide is the same on the light introducing side and the other end side of the optical waveguide.

(Effect of the Invention) According to the present invention, as described above, the optical waveguides and the transparent electrodes are arranged in a matrix, and an electric field is applied to a specific optical waveguide on which light is incident to partially leak light. As a result, clear pixels can be obtained, and the response speed is a few microseconds, which is faster than that of the crystal type, which makes it easy to colorize and easily output intermediate colors. Since the upper and lower electrodes are each divided in the width direction and have an interference filter function, the amount of light leaked increases due to the wavelength selectivity and the effect of increasing the reflected light, and thus the flat display device having a reliable structure is simple. There is a real benefit that can be provided.

[Brief description of drawings]

1 is a sectional view of a flat panel display device according to the present invention, and FIG. 2 is a schematic plan view of the device of FIG. 10 …… Flat panel display, 12 …… Optical waveguide, 14 …… Upper transparent electrode, 16 …… Lower electrode, 24 …… Light source, j1, j2, j3 to jp …… Split part of upper and lower electrodes.

Claims (1)

[Claims] 1. N optical waveguides arranged in parallel with each other and having an electro-optical effect, and arranged in parallel with each other in a matrix on the optical waveguides so as to intersect with the optical waveguides. The M upper electrodes and the upper electrode are arranged in parallel to the upper electrode on the side opposite to the upper electrode with the optical waveguide interposed therebetween, and the upper electrode is shifted forward and backward with respect to the traveling direction of light. And M lower electrodes to which a voltage is selectively applied so as to generate an electric field in the optical waveguide between the two, and the M upper and lower electrodes are divided into P in the width direction and interfere with each other. A flat display characterized by having a filter function and applying a voltage between the upper and lower electrodes to leak light in the optical waveguide by the interference filter function in the vicinity of the intersection of the upper electrode and the optical waveguide. Dress .