JPS61118789A - Light apparatus for liquid crystal display element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an illumination device for a liquid crystal display element that can be used in a large screen display device comprising a plurality of transmissive liquid crystal display elements.

Problems with conventional structure In recent years, in addition to nine-screen display devices that use three primary color fluorescent lamps or three primary color cathode ray chains (CRTs), liquid crystals have been used as optical switches, and three A method using primary color filters is being considered.

A conventional illumination system for a liquid crystal display element will be described below with reference to the drawings.

In FIG. 2, light emitted from a white fluorescent lamp 4 enters a liquid crystal display (LCD) 1, and the LCD adjusts the amount of light passing therethrough according to an external signal, and enters a layer of a color filter 3.

The filter is a three-color filter corresponding to one picture element,
It consists of B, G, and R (B, G, and R refer to slanted color filters that turn white light into backlight, green light, and red light, respectively). This constitutes a picture element and displays a color image at position 7 on the front panel 6.

The size of a single liquid crystal display element that can currently be manufactured ranges from 6 inches to 12 inches square, and in order to construct a larger screen, it is necessary to arrange multiple panels. However, since the wiring portion 2 is generally located at the edge of a liquid crystal display element, there has been a problem in that the joint 6 appears as a black line (8 in FIG. 3) in a large screen configuration.

This article relates to lighting devices for liquid crystal display elements.

In order to form a surface, the bottom part is on the liquid crystal display side, and the surface is inclined from the picture element on the outer edge of the adjacent liquid crystal part toward the apex located on the light source side, at the position corresponding to the joint,
A long triangular prism is placed along the seam, and the illumination light is incident diagonally to the edge of the liquid crystal display element, so that the seam is not noticeable on the front panel of the liquid crystal display element. As a result, the joints are not visible as black lines and are no longer independent.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 illustrates the invention.

In addition to the basic components shown in FIG. 2, a prism 1o is added. The operation of the embodiment configured as above will be described below. A beam of light 11 emitted from the illumination light source 4 is bent by a prism 10 in the direction of the LCD joint, passes through the picture elements 12 of I and CD, and passes through the pixels 12 on the front panel 6.
It is irradiated to position 3. On the other hand, the ray bundle 14 is transmitted through the prism 1o
It is bent in the direction of the first seam of the LCD, and the LC
It passes through the picture element 16 of D and reaches 16 on the front panel 6. If 13 and 16 are placed adjacent to each other with a gap,
Information about picture elements 12 and 1g on the outer edge of the LCI (LCI) is shown on 13.16, where no light originally came, so if the front panel is configured to use that as a light source and emit light in all directions. , a person viewing this display device from the front can see the image as if there were no L(jD joints).

As described above, according to this embodiment, by adding an illumination light prism, it is possible to display a large screen with unnoticeable seams.

As shown in FIG. 4, the length l of the bottom surface of the prism is selected depending on how many picture elements are used for this joint. That is, the length of the part without picture elements of each IID is 4. If the required number of pixels is n1 and the size of the pixel is dl, then (1>ndl + 2(1).The inclination angle M becomes larger if the refractive index of the prism material is small, and the distance between the LCD and the front panel The shorter the length, the larger it will be.

In addition to the general light source, the illumination device of the present invention has prisms arranged along the rows of a plurality of LCJD boards, so the prisms are arranged in a mesh pattern as shown in Fig. 6. Consists of Neftwork. The intersection between the prisms is shaped like a horizontal prism passing through a vertical prism.

In other embodiments, the shape of the prism in the above configuration is such that the bending angle of the light beam is gradually increased toward the joint, as shown in Figure 1, in order to smoothly connect the part without the prism to the part with the prism. A shape is taken.

As is clear from the detailed description of the invention, the present invention provides a prism with the liquid crystal section as the bottom surface on the illumination light side of the joint of the liquid crystal display element, thereby reducing the display area near the outer edge of the liquid crystal display element. The luminous flux is obliquely incident on the screen, covering the seams through which no light would normally pass, and providing an excellent effect in that the seams can be displayed without being visible.

Furthermore, by dividing the inclined surface of the prism into several parts having different angles, it is possible to obtain the effect that the natural feeling of the connecting part can be further strengthened.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the basic components of the present invention, Fig. 2 is a diagram showing a conventional illumination system, Fig. 3 is a diagram showing a displayed image when using the conventional illumination system, and Fig. 4 is a diagram showing a prism. FIG. 5 is a diagram showing the arrangement of prisms, which are the constituent elements of the illumination device according to the present invention, and FIG. 6 is a diagram showing the improved shape of the prism. 1...Liquid crystal section, 2...Wiring section of liquid crystal section, 3...Color filter, 4...Light source,
6...front panel, e...joint,
7... Image display section, 8... Black stripes at joints, 1o... Prism, 11.14...
... Luminous flux, 12.15 ... Picture element, 13.16
・・・・・・Position of adjacent picture elements on the front panel. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (2)

[Claims] (1) When forming a large-screen liquid crystal display element by arranging multiple transmissive liquid crystal display elements, a triangular prism with the liquid crystal display side as the bottom and the light source side as the apex is placed at the joint of the liquid crystal display elements. An illumination device for a liquid crystal display element, characterized in that a prism is arranged to make illumination light obliquely incident on the outer edge of the liquid crystal display element so that the joints are not noticeable on the front panel of the liquid crystal display element. (2) The angle of inclination of the triangular prism is small near the bottom and increases toward the apex in several steps.
The lighting device for a liquid crystal display element according to claim 1, characterized in that the joint on the front panel of the liquid crystal display element is made more natural and unnoticeable.