JPS60227233A - Plane image display panel device - Google Patents

Abstract

PURPOSE:To form a large-sized image screen by providing light guides of which the center spacing expands with an increase in distance from a plane image panel for each of picture elements to the front face of the panel and providing means for bending rays and means for diffusing light at the middle or end thereof. CONSTITUTION:The light guide means 4 are provided for each of picture elements to the front face of the liquid crystal panel 1 and further a Fresnel lens 5 is provided in front thereof. A lenticular lens 6 is further superposed in front thereof. Light guide plates 17 are formed by assembling this metallic sheets into a grating shape and the central spacing thereof increases with an increase in distance from the picture element thus acting to expand the central spacing of the picture elements. The lens 5 parallels approximately the ray 19 advancing through the center 18 of each light guide from each picture element and further the light spreading horizontally when viewed from an observer is emitted from the lens 6 so that the horizontal visual field is expanded. If such liquid crystal panels are two-dimensionally arrayed, the joints are invisible to the observer and the luminance is uniformly distributed. The large image screen having a wide visual field angle and giving no a sense of incompativility is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a flat image display panel device,
In particular, the present invention relates to a flat image display panel device in which a plurality of flat image display panels are two-dimensionally arranged to increase the screen size.

Conventional Structure and Problems There is a well-known method of arranging a plurality of flat image display panels, such as liquid crystal panels, two-dimensionally in order to realize a large-screen liquid crystal panel.

However, as shown in FIG. 1, since the liquid crystal panel 1 has a spacer around it for sealing liquid crystal, it has an invalid screen area 2 around it. When a plurality of liquid crystal panels 1 are two-dimensionally arranged as shown in FIG. 2, a grid-like invalid screen area 3 is generated. Therefore, the observer can see the grid pattern 3.
It felt strange, as it felt like I was looking at an image through the lens.

Purpose of the Invention The present invention provides a planar image for eliminating the above-mentioned grid pattern and projecting a large-screen image that does not give a strange feeling when a plurality of planar image display panels are two-dimensionally arranged. A display panel device is provided.

Structure of the Invention The flat image display panel device according to the present invention includes light guide means arranged in front of the flat image display panel for each picture element, the distance between the centers of which increases as the distance from the flat image display panel increases, and each of the light guide means A light beam bending means and a light diffusing means are arranged at the end or in the middle of the screen to prevent a grid-like invalid screen area from appearing when a plurality of flat image display panels are arranged two-dimensionally, and to prevent the screen from appearing. This prevents uneven brightness throughout the display and further widens the viewing angle.

DESCRIPTION OF EMBODIMENTS A flat image display panel device according to the present invention will be described with reference to the accompanying drawings. FIG. 3 shows a cross section of an embodiment of the flat image display panel device according to the present invention. A light guide means 4 is disposed in front of the liquid crystal panel 1, and a Fresnel lens 5 as a light bending means and a lenticular lens 6 as a light diffusion means are further disposed thereon. Light guide means 4. The external dimensions of the Fresnel lens 6 and the lenticular lens 6 are the same.

The liquid crystal panel 1 has two transparent substrates 7 and 8 stacked on top of each other with a surrounding spacer 9 in between, and a liquid crystal 1o is sealed in an internal sealed space. On the surface of the transparent substrate 7.8 on the liquid crystal 1o side, a large number of transparent electrodes 11.12 are arranged in parallel at required intervals. The transparent electrodes 11 and 12 are arranged in directions perpendicular to each other, and both transparent electrodes 11
, 12 each constitute one picture element 13.

Polarizing plates 14 and 15 are arranged on the outer surfaces of the transparent substrates 7 and 8. A planar light source 16 is arranged behind the liquid crystal panel 1, and each picture element 13 becomes transparent due to the signal voltage applied to both transparent electrodes 11 and 12. The emitted light passes through and is washed away.

As shown in FIG. 4, the light guide means 4 is a combination of thin metal light guide plates 17 in a lattice shape, and the distance between the centers thereof increases as the distance from the liquid crystal panel 1 increases. The end of each element of the light guide means 4 on the liquid crystal panel 1 side is connected to the liquid crystal panel 1.
It overlaps each picture element. The overall external dimensions of the opposite end of the light guide means 4 are slightly larger than the overall external dimensions of the liquid crystal panel 1. The light guide means 4 functions to gradually widen the distance between the centers of adjacent picture elements 13 of the image displayed on the liquid crystal panel 1. As a result, the invalid screen area caused by the spacer 9 around the liquid crystal panel 1 is eliminated.

This light guide means 4 prevents the light emitted from each picture element 13 of the liquid crystal panel 1 from mixing with each other, but it is possible to prevent the light emitted from each picture element 13 of the liquid crystal panel 1 from mixing with each other by vapor-depositing an aluminum thin film on the light guide plate 17 that constitutes the light guide means 4. It is also possible to increase the surface reflectance of the light guide plate 17 and prevent the amount of light passing through the light guide means 4 from attenuating.

The Fresnel lens 6 changes the light ray 19 traveling along the central axis 18 of each element of the light guide means 4 into a light ray 21 parallel or nearly parallel to the normal 2o of the liquid crystal panel 1. When the Fresnel lens 5 is not used, as shown in FIG. It doesn't appear. Moreover, since the direction that provides the maximum brightness almost coincides with the central axis 18 of each element of the light guide 4, for example, when the observer 23 looks at the liquid crystal panel 1 from the direction of arrow B, The image at the far end 24 appears much darker than other locations. On the other hand, when the Fresnel lens 5 is used, as shown in FIG. 3, the light rays 21 giving the maximum brightness are parallel to all picture elements, so the directional dependence of the brightness of each picture element is almost the same. This can be understood from the fact that when the light guide 4 is observed through the Fresnel lens 6, all the light guide plates 17 appear to be approximately parallel to each other. By using the Fresnel lens 6 in this manner, the brightness distribution over the entire screen can be made uniform no matter which direction the liquid crystal panel 1 is viewed from.

The lenticular lens 6 has a cylindrical surface 27 regularly and parallelly formed on one surface of a single transparent plate 26, which is long in the vertical direction when viewed from the viewer.

When the parallel light rays 21 exiting the Fresnel lens 6 enter the lenticular lens 6, light that is spread in the horizontal direction as viewed from the viewer emerges, so that the horizontal viewing angle can be widened. On the other hand, the lenticular lens 6 hardly changes the vertical viewing angle. Generally, in large screen displays, it is not necessary to make the vertical viewing angle very large, but it is desired to make the horizontal viewing angle as wide as possible. Therefore, it is very important to use lenticular lenses in liquid crystal panel devices as in the present invention. Seems like a reasonable measure.

The connection between the liquid crystal panel 1 and the light guide means 4 and the connection between the light guide means 4 and the Fresnel lens 6 can be easily realized by applying an adhesive to both ends of the light guide plate 17 and overlapping them. In addition, the lenticular lens 6 and the collane lens 5
This connection can be easily achieved by attaching a connecting plate 28, which is sufficiently thin compared to the size of one picture element 13, to the end surfaces of the lenticular lens 6 and the Fresnel lens 6 using an adhesive.

As shown in FIG. 6, the third
By two-dimensionally arranging a large number of the liquid crystal panel devices shown in the figure, a large-screen liquid crystal panel device can be realized. Each liquid crystal panel device is fixed to a grid frame 29.

In this way, each liquid crystal panel device is arranged without gaps to the viewer, and the viewer sees it as if it were one liquid crystal panel, so that the viewer does not feel any strangeness.

Other embodiments of the present invention will be described below.

FIG. 7 shows another embodiment of the light guide means. The light guide means 3o is composed of transparent square columns 32 having aluminum thin films 31 deposited on their sides, and arranged so that the distance between their central axes 33 increases as the distance from the liquid crystal panel 1 increases. In other words, the light guide plate 17 of the light guide 4 shown in FIG. 3 is changed to an aluminum vapor-deposited film, and the air inside the light guide 4 is changed to a solid.

The orientation of the lens surface 34 of the Fresnel lens 5 and the orientation of the lens surface 27 of the lenticular lens 6 shown in FIG. 11.3 may be directed toward the liquid crystal panel 1 side or toward the viewer side. Furthermore, the Fresnel lens 6 may take any form as long as it is a positive lens means. For example, as shown in FIG.
4 may be inserted.

FIG. 9 shows an example in which a light diffusing material is used as the light diffusing means. A light diffusing material is distributed inside the Fresnel lens 34. This light diffusing material can widen the viewing angle in the horizontal and vertical directions. Note that the light diffusing material may be distributed on the surface 36 of the Fresnel lens 36 on the liquid crystal panel 1 side or the surface 37 on the opposite side.

FIG. 10 shows an example in which the mud Fresnel lens 5 and the lenticular lens 6 shown in FIG. 3 are constructed in one piece. A Fresnel lens 39 is formed on the surface of one transparent plate 38 on the liquid crystal panel 1 side, and a lenticular lens 4o is formed on the opposite surface. Since the connecting plate 28 shown in FIG. 3 is used, when a large number of liquid crystal panel devices shown in FIG. , you can avoid feeling any discomfort at all. Furthermore, since the number of refractive surfaces is minimized to two, the loss of light amount due to surface reflection is further reduced.

FIG. 11 shows the lenticular lens 4 shown in FIG.
This shows an example in which the lens 41 is replaced with a lenticular lens 41 that has a very wide horizontal viewing angle by utilizing total internal reflection. This lenticular lens 41 has one element 42
The cross-sectional shape is trapezoidal, and the upper surface 43 is cylindrical and the side surface 44 is straight. The parallel rays coming out of the Fresnel lens 39 are a ray 46 incident on the top surface 43 and a ray 46 incident on the side surface 44.
The light ray 46 incident on the light beam is divided into two parts. Light rays 45 incident on the top surface 42 are laterally diffused by the lens action of the cylindrical surface, but the viewing angle is small. On the other hand, the light ray 46 incident on the side surface 44 is bent laterally by total reflection on the side surface 44, and further bent laterally on the upper surface 43,
Diffused over a wide viewing angle area. Therefore, the viewing angle can be made very wide. Note that the cross-sectional shape of the lenticular lens is not limited to the shape shown in FIG. 11, but can also be shaped as shown in FIGS. 12 a, b, c, d, and e. In FIG. 12a, the upper surface 43 of the trapezoidal lenticular element 42 shown in FIG. 11 is changed to a cylindrical surface 47 that is concave toward the outside.

In FIG. 12, trapezoidal lenticular elements 41 and cylindrical lenticular elements 48 are alternately formed. In FIG. 12C, the upper surface 41 of FIG. 12 is made into a cylindrical surface 47 that is concave toward the outside.

FIG. 12d shows an upper surface 43 of the trapezoidal lenticular element 42 shown in FIG. 11 having two cylindrical surfaces 49. FIG. 12 θ shows an arrangement in which trapezoidal lenticular elements and cylindrical lenticular elements 48 shown in FIG. 12d are alternately formed.

The flat image display panel device according to the present invention is not limited to liquid crystal panels, but can be applied to any flat image display panels such as electroluminescent display panels, plasma display panels, photochromic display panels, and LED panels.

Effects of the Invention As explained above, in the flat image display panel device according to the present invention, when a large number of these flat image display panel devices are arranged two-dimensionally, an invalid screen area that appears as a grid pattern to the viewer is visible. In addition, the brightness distribution across the entire screen is almost uniform, and the viewing angle is wide. has a big effect.

[Brief explanation of drawings]

Fig. 1 is a schematic external view of a typical liquid crystal panel, Fig. 2 is an explanatory diagram regarding the problems of the liquid crystal panel shown in Fig. 1, and Fig. 3 is an illustration of the problems of the liquid crystal panel shown in Fig.
The figure is a cross-sectional view showing one embodiment of the flat image display panel device according to the present invention, FIG. 4 is a perspective view showing one embodiment of the light guide means, and FIG. 6 is an explanation for explaining the function of the Fresnel lens. 6 is a cross-sectional view of a flat image display panel device formed by two-dimensionally arranging a large number of the flat image display panel devices shown in FIG. 3, and FIG. 7 is a cross-sectional view of another embodiment of the light guide means. 8, 9, 10 and 11 are cross-sectional views for illustrating other embodiments of the light bending means and the light diffusing means, and FIGS. 12a and 12b , c, d, and e are route maps for showing configuration examples of lenticular lenses. 1...Liquid crystal panel, 4...Light guide means, 6...Fresnel lens, 6...Lenticular lens, 3o...Light guide means,
34.35... Fresnel lens, 38...
・Transparent plate. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 1 Figure 2 Figure 3, ? /1 Figure 4 4'5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11

Claims (1)

[Scope of Claims] (1) On the front surface of a flat image display panel, a light guide means is disposed for each picture element, the distance between the centers of which increases as the distance from the flat image display panel increases, and the ends of the light guide means or A flat image display panel device characterized in that a light beam bending means and a light diffusing means are arranged in the middle. (Odor) The light guiding means is characterized in that the overall external dimensions on the side opposite to the flat image display panel are the same as or larger than the overall external dimensions of the flat image display panel. A flat image display panel device according to claim (1), characterized in that the light guide means is a combination of thin plates in a lattice shape. A patent claim characterized in that the bending means bends the light beam passing on the central axis of each of the light guide means in the normal direction of the flat image display panel or in a direction close to the normal line. A flat image display panel device according to claim (1). (@ A flat image display panel device according to claim (1), wherein the light beam bending means is a Fresnel lens. (6 ) The light diffusing means is a flat image display panel device according to claim 1 (@), characterized in that the light diffusing means is one in which a diffusing material is distributed inside or on the surface of the Fresnel lens. A flat image display panel device according to claim (1), characterized in that the device is a curar lens. A flat image display panel device according to claim 1, characterized in that the liquid crystal panel side is a Fresnel lens, and the surface facing the liquid crystal panel is a Fresnel lens at the end or middle of the light guide means. A flat image display panel device according to claim (1), characterized in that a single transparent plate whose opposite surface is a lenticular lens is disposed.(1o) The lenticular lens is A flat image display panel device according to claim 1, characterized in that the cross-sectional shape of the element is trapezoidal. (11) The light guide means, the light beam bending means, and the light diffusing means are The flat image display panel device according to claim 1, wherein the width of the invalid screen area around the external picture element is sufficiently smaller than the thickness of each picture element.