JPH052238B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a transmissive liquid crystal display device using a transmissive liquid crystal display panel that can be used in liquid crystal television receivers and the like.

BACKGROUND ART In recent years, liquid crystal television receivers using liquid crystal display panels have been put into practical use.

Such a liquid crystal television receiver is small and lightweight, making it useful as a portable television; however, since the liquid crystal display panel itself does not emit light, it requires some kind of light source. As an example of such a liquid crystal television receiver, conventionally,
Some devices use a transmissive liquid crystal display panel and have a light diffusing plate and a light source section on the back side of the panel. In this case, the light source section used includes a reflector whose inner surface is a substantially parabolic reflecting surface, and a light source placed at the focal point of the reflector.

Problems to be Solved by the Invention However, such conventional devices have a problem in that the depth of the reflector in the light source section is large, resulting in an increase in the overall depth of the LCD television receiver, etc. Ta.

SUMMARY OF THE INVENTION An object of the present invention is to solve these conventional problems and provide a transmissive liquid crystal display device that can reduce the depth of the light source section and make the entire device compact.

Means for Solving the Problems The transmissive liquid crystal display device of the present invention has a transmissive liquid crystal display panel, a light diffusing plate, and a light source section, and a reflector used in the light source section is used to emit almost no light. An object-like reflective surface is divided into multiple surfaces, and
The device is characterized in that each divided portion has an inner surface that is shifted forward toward the center so as to reduce the depth.

Function In this way, by dividing the inner surface of the reflector into multiple parts and shifting each divided part forward toward the center, the depth of the reflector can be reduced to that of a conventional continuous inner surface. It is possible to significantly reduce the size of the display device compared to the conventional one, and thus a small and thin display device can be realized.

Embodiment Hereinafter, a transmissive liquid crystal television receiver according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows an exploded view of the main parts of the structure. In the figure, 1 is a transmissive liquid crystal display panel, 2 is a light diffusion plate placed on the back side of the panel to reduce unevenness of light from the light source and illuminate the liquid crystal display panel 1 with uniform brightness, and 3 is a light diffusion plate placed on the back side of the panel to reduce unevenness of light from the light source and illuminate the liquid crystal display panel 1 with uniform brightness. This is the light source section placed on the back side. The light source section 3 is composed of a reflector 5 whose inner surface is a reflective surface 4, and a light source 6 disposed approximately at the focal point of the reflector 5. As the light source 6, a fluorescent tube or the like can be used.

The reflective surface 4 of the reflector 5 is formed by dividing the original substantially parabolic reflective surface (broken line) into a plurality of surfaces 4a, 4b, 4c, etc., as shown in a partially enlarged view of FIG. , each divided portion 4a, 4b, 4c, . . . is configured to have an inner surface shape that is shifted forward as it approaches the center.

If a reflector 5 having such a shape is used, the depth of the reflector 5 can be reduced to A compared to the conventional B, as shown in FIG.
The depth of the entire device can be reduced to make it smaller and thinner. Furthermore, since each divided portion is obtained by dividing the original parabolic shape, it is possible to obtain almost the same effect of reflecting the light from the light source 6 as that of a paraboloid.

Note that when the reflective surface 4 of the reflector 5 is configured with a large number of divided parts and shifted forward, the depth becomes smaller, so that more direct light from the light source 6 hits the light diffusing plate 2. In this case, the center part becomes too bright, and the part slightly away from the center part may suddenly become dark. Therefore, in such a case, as shown in FIG. 4, each divided portion of the reflective surface 4 is changed from the original so that a large amount of reflected light is focused on a portion slightly away from the center portion of the light diffusing plate 2. By arranging them at slightly different angles than the parabolic shape, changes in brightness can be reduced and brightness can be approximated to be uniform. Furthermore, similar light distribution may be obtained by varying the area of each divided portion.

Furthermore, when the reflective surface 5 of the reflector 4 is divided and arranged so as to be shifted forward, the boundary between each divided portion casts a shadow on the light source 6, as shown in FIG. This may cause uneven brightness or horizontal stripes. In such a case, as shown in Fig. 4, the back side of the light diffusing plate should be made into a glossy surface or a half mirror surface.
Uniform brightness can be obtained by repeatedly reflecting the light from the light source 6 between the light diffusing plate 2 and the reflecting surface 5.

Effects of the Invention As described above, according to the present invention, the reflective surface of the reflector of the light source section is divided and shifted forward, thereby reducing the overall depth and making it compact.
This makes it possible to realize a thin liquid crystal display device.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a transmissive liquid crystal display device according to an embodiment of the present invention, FIG. 2 is an enlarged view of its main parts, FIG. 3 is a side view thereof, and FIGS. 4A and B are front views thereof. and a cross-sectional side view. 1...Liquid crystal display panel, 2...Light diffusion plate, 3...
...Light source section, 4...Reflecting surface, 5...Reflector, 6...
light source.

Claims (1)

[Claims] 1. A transmissive liquid crystal display panel, a light diffusing plate provided on the back side of the liquid crystal display panel, and a light source section provided on the back side of the light diffusing plate, The light source section includes a reflector having an inner surface in which a substantially parabolic reflecting surface is divided into a plurality of surfaces and each divided portion is shifted forward toward the center so as to reduce the depth; 1. A transmissive liquid crystal display device, comprising: a light source placed approximately at the focal point of a parabolic reflecting surface. 2. The transmissive liquid crystal display device according to claim 1, wherein each divided portion of the reflector is arranged at a different angle from the original parabolic shape. 3. A transmissive liquid crystal display device according to claim 1 or 2, wherein each divided portion of the reflector has a different area. 4. The transmission type liquid crystal display device according to claim 1, wherein the back surface of the light diffusing plate is a glossy surface or a half mirror surface.