JPS629317A - Liquid crystal display - Google Patents

Abstract

PURPOSE:To reduce visual angle dependency and to make individual picture elements inconspicuous by forming a distributed index area which is smaller in size than a picture element and has variation in refractive index internally over the entire internal surface of a front-side substrate. CONSTITUTION:A distributed index area 6 which is smaller in size than a pic ture element 2 and has variation in refractive index internally is formed over the entire internal surface of the front substrate 5 of a liquid crystal display 5. When an incident light beam 7 exists from a picture element 2, it is bent in an area 6 in various directions, so contrast is improved and a visual angle is increased. Further, the end part of a picture element is seen as if it were superposed upon an adjacent picture element through light scattering operation and individual picture elements can be made inconspicuous.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to liquid crystal displays.

[Conventional technology]

Traditional liquid crystal displays are widely used in watches, calculators, hand belt computers, television watches, pocket color televisions, etc.

[Problem that the invention seeks to solve]

However, these liquid crystal displays have a major problem in that they are viewing angle dependent. In addition, in liquid crystal pocket color televisions and the like that display moving images, there is a problem in that each pixel easily catches the eye.

The present invention solves the above problems, and its purpose is to:
An object of the present invention is to provide a liquid crystal display with less viewing angle dependence than before. Another purpose is to provide a liquid crystal display in which each pixel is unnoticeable when displaying moving images.

[Means for solving problems]

In the liquid crystal display of the present invention, of the two substrates of the liquid crystal display, on the inner surface of the substrate in front of the viewer,
A refractive index distribution region including a change in refractive index on a scale smaller than that of a pixel is formed over at least the entire display portion.

[Effect]

According to the above structure of the present invention, as shown in FIG. 1, the light emitted from the pixel is bent in any direction by the light scattering effect of the refractive index distribution region, which results in good contrast. The viewing angle is wider than before. Further, as shown in FIG. 2, the edge portions of the pixels appear to overlap with adjacent pixels due to the light scattering effect of the refractive index distribution region, and each pixel becomes less conspicuous.

This will be explained in detail below using examples.

〔Example〕

A liquid crystal video display (240 x 240 pixels) that has a simple matrix structure and displays moving images using time-division drive.
A pixel pitch of 140μ5×1doμm, monochrome) was produced. Next, using glass containing 08 as a raw material, we fabricated a microlens array (lens diameter 20 μm, 20 μm pitch) using the ion exchange method to lower the refractive index inside the lens, and the refractive index at a size smaller than that of the pixels was fabricated. The substrate was made such that a refractive index distribution region including a change therein was formed over the entire substrate. A liquid crystal panel was fabricated using it as one side substrate, and a liquid crystal video display (I, V
D) was produced.

When a visual comparison test was conducted by displaying actual television broadcasts on the two types of liquid crystal video displays, it was clear that the latter was superior as shown below.

Although this example shows an example in which light-divergent microlenses are integrated on the substrate, the present invention is not limited to this. If the refractive index distribution region including the refractive index distribution region is formed over the entire display portion, the light scattering function can be efficiently performed, so that the same effect as that of this embodiment can be obtained. For example, when creating a substrate using an ion exchange reaction, a mask pattern such as the one obtained when openings other than circular (for example, square, triangular, irregular shapes, etc.) are provided. A substrate may also be used. It is also obvious that light-focusing microlenses may be integrated. Further, the method for manufacturing the substrate is not limited to the ion exchange method.

This example is an example of a monochrome liquid crystal display with a simple matrix structure. Similar effects can be obtained in active matrix color liquid crystal displays using T-substrates, as well as wall-mounted TVs, large-scale outdoor displays, and ultra-large-scale displays.

〔Effect of the invention〕

As described above, the liquid crystal display of the present invention has a refractive index distribution region that includes a change in refractive index on a scale smaller than that of a pixel on the inner surface of the substrate in front of the viewer, which covers the entire display area. Since it is formed over a wide area, it has the effect that viewing angle dependence is smaller than that of conventional liquid crystal displays. It also has the effect that each pixel is not noticeable when displaying a moving image or the like.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a liquid crystal display for explaining the reason why the liquid crystal display of the present invention has little viewing angle dependence. FIG. 2 is a cross-sectional view of the liquid crystal display for explaining the reason why each pixel of the liquid crystal display of the present invention is not conspicuous. 1... Part of the liquid crystal display of the present invention 2...
... Pixel 3 ... Pixel gap 4 ... Beautiful board from the viewer's perspective 5 ... Board 6 in front of the viewer... ...
Refractive index distribution area 7... Group of rays incident at an angle with good contrast 8... Group of rays scattered in the refractive index distribution area 9.
...more than a group of rays incident on the nearest example of a pixel

Claims (1)

[Claims] A refractive index distribution region containing changes in refractive index on a scale smaller than a pixel is formed on the inner surface of the one in front of the viewer of the two substrates of a liquid crystal display, covering at least the entire display area. A liquid crystal display characterized by: