JPH03269518A - Structure of light diffusing plate of liquid crystal display device - Google Patents

Abstract

PURPOSE:To allow easy production and assembly and the formation to a smaller thickness and to obtain the inexpensive structure of the light diffusing plate as well as to improve the deficiency of the light quantity in the peripheral part of a panel by forming selective light shielding patterns directly onto the light diffusing plate or selectively changing the thickness of the light diffusing plate. CONSTITUTION:A light source 11 is disposed behind the liquid crystal panel 13 and the light emitted by this light source 11 is uniformly difufsed over the entire part of the liquid crystal panel 13 in order to display characters and graphics of a high contrast on the compact light crystal panel 13 for a word processor, personal computer, etc. The light diffusing plate 12 formed with the selective light shielding patterns 12b directly in the positions strongly irradiated with the light of the light source 11 is fixed to a lamp house 10 by using a double-coated adhesive tape 12a for the above-mentioned purposed. The lighting curtain function is integrated with the light diffusing plate 12 in this way, by which the production is facilitated and the ease of assembly is assured. In addition, the total reflection loss of light and the deficiency of the light quantity are eliminated and the contrast of the liquid crystal display is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a light diffusing plate structure for a liquid crystal display device having a light source.

[Prior Art] A light diffusing plate structure of a conventional liquid crystal display device is shown in FIG. That is, in order to uniformly apply the light emitted by the light source 11 to the entire liquid crystal panel 15, the riding curtain 1 is provided with a light shielding pattern 1b formed in advance at a position where the light from the light source 11 is strongly hit in relation to the light source 11. is fixed to the lamp house 10 using double-sided tape 1α.

A light diffusion plate 12 that further diffuses the light passing through the lighting curtain 1 is fixed to the lamp house 10 using double-sided tape 12 (Z).

[Problems to be Solved by the Invention] In the conventional light diffusing plate structure of a liquid crystal display device, the lighting curtain 1 and the light diffusing plate 12 shown in FIG. This increased costs and assembly costs, which led to an increase in costs. Furthermore, the thick barrel of the structure was also an obstacle to making it thinner.

In addition, by inserting a material between the diffuser plate and the lamp, the light passing through the member passes through the air on its way from the member to the diffuser plate, so the light emitted from the member is totally reflected, causing light to pass through the air around the diffuser plate. This caused a loss in the passage of light, causing an insufficient amount of light.

The present invention solves these conventional problems, provides an inexpensive light diffusing plate structure that is easy to manufacture and assemble, contributes to a reduction in thickness, and improves the lack of light in the peripheral area of the panel.

[Means for Solving the Problems] The light diffusing plate structure of the liquid crystal display device of the present invention includes forming a selective light shielding pattern directly on the light diffusing plate or selectively changing the thickness of the light diffusing plate. It is characterized by:

[Example] A first example of the light diffusing plate structure of the liquid crystal display device of the present invention is described below.
This will be explained using figures.

Reference numeral 13 is a liquid crystal panel, which is used in word processors, personal computers, etc., in order to display two characters and figures with high contrast on the liquid crystal panel 15 in a more compact manner.
The above requirement is achieved by arranging the light source 11 behind the light source 11.

In order to uniformly apply the light emitted by the light source 11 to the entire liquid crystal panel 13, in advance, in the positional relationship with the light source 11,
A light diffusing plate 12 with a selective light shielding pattern 12h formed thereon is directly attached to the double-sided tape 12 in a position where the light from the light source 11 is strongly hit.
It is fixed to the lamp house 10 using α.

In this way, the integrated structure of the lighting curtain
As shown in the figure, it is also possible to use a method of changing the thickness of the light diffusing plate according to the strength of the light source, which is innovative in making the liquid crystal display device thinner and more compact.

Also, regarding the method of fixing the light diffusing plate, in the present invention, double-sided tape is used, but as shown in Fig. 4,
The light diffusing plate fitting part 1 is installed in the lamp house 10 in advance.
Using the method of molding 0α and fitting the light diffusing plate 12 in one-touch, the assembly cost is reduced and the structure allows the light diffusing plate 12 to be easily disassembled when the light source 11 is damaged. Alternatively, a fixed structure using screws or adhesive may be used.

[Effects of the Invention] According to the present invention, by integrating the lighting curtain function into the light diffusion plate, it is easy to manufacture and easy to assemble.
It is possible to provide a light diffusing plate structure that is highly mass-producible.

Furthermore, by integrating, the number of parts is reduced and a thinner light diffuser plate structure can be realized, and by eliminating the need for a member between the diffuser plate and the lamp, total reflection loss of light is eliminated.
This solves the problem of insufficient light and dramatically increases the contrast of liquid crystal displays.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the light diffusing plate structure of the present invention. FIG. 2 is a perspective view of a conventional example, and FIG. WJ3 is a perspective view of another embodiment. FIG. 4(α) is an enlarged view of part A in FIG. 4(b). FIG. 4(b) is a sectional view of another embodiment. 10...Lamp house 11...Light source 12...Light diffusion plate 15...Liquid crystal panel・・・・・・−・Lighting curtain or more

Claims (1)

[Claims] In the light diffusion plate structure of a liquid crystal display device that displays characters or figures using a light diffusion plate that diffuses light from a light source,
A light diffusing plate structure for a liquid crystal display device, characterized in that a selective light shielding pattern is directly formed on the light diffusing plate, or the thickness of the light diffusing plate is selectively changed.