JPH04168423A - Liquid crystal display element - Google Patents

Abstract

PURPOSE:To effectively utilize the circumferential light or the incident light from an illuminating light source by forming a concave lens in an array form on a glass substrate on which a common picture element electrode is formed so that nearly the central axis of the concave lens is conformed with nearly the center of a light shielding part. CONSTITUTION:In a liquid crystal display element, a liquid crystal driving part and a wiring part 17 are covered with a light shielding film 14 to stabilize the characteristic of a driving element. On the light shielding part, a band concave lens array 11 is formed, and nearly the center axis of the concave lens is situated about in the center part of the light shielding part. The incident light 14 onto the light shielding part is curved in its optical path by the concave lens, and the most part is guided to a picture element opening part 13. Thus, the incident light onto the light shielding part can be also guided to a transparent picture element opening part 16 without being limited by the size of the picture element opening part 13, and a bright liquid crystal display element having a high light utilizing efficiency can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid crystal display element, and particularly to a light-receiving type liquid crystal display element capable of displaying a bright screen.

[Conventional technology]

A liquid crystal display element is an element that utilizes the electro-optical effect of liquid crystal to control the amount of transmitted light and transmit image information and the like. Because it is possible to reduce size and weight and reduce power consumption during driving,
Practical use as thin display elements is progressing rapidly.

[Problem to be solved by the invention]

In order to improve the display image quality of a liquid crystal display element, it is essential to increase the definition of the element. However, on the other hand, increasing the resolution of devices leads to a decrease in the brightness and contrast of displayed images.Generally, liquid crystal display devices consist of transparent pixel apertures, liquid crystal drive sections, wiring sections, etc., and these are configured in a planar manner. ing.

The liquid crystal drive section and the wiring section always have a certain finite size due to their function and manufacturing process, so the higher the pixel density of the liquid crystal display element, the higher the aperture ratio (the area ratio of the transparent pixel aperture to the pixel). ) decreases and the displayed image becomes darker. Therefore, when increasing the definition of liquid crystal display elements, an important point is how to improve the pixel density without reducing the aperture ratio (in other words, the light utilization efficiency).

SUMMARY OF THE INVENTION The present invention aims to solve the above-mentioned problems, and its purpose is to provide a liquid crystal display element with a novel structure that can effectively utilize ambient light or incident light from an illumination light source for display purposes. It is about providing.

[Means to solve the problem]

In order to solve the above problems, the liquid crystal display element of the present invention is an active matrix or multi-matrix liquid crystal display device in which a transparent pixel opening and a light shielding part consisting of a liquid crystal drive part, a wiring part, etc. are regularly arranged. The element is characterized in that concave lenses are formed in an array on a glass substrate on which a common pixel electrode of the liquid crystal display element is formed, such that the approximate central axis of the concave lenses coincides with the approximate center of the light shielding part.

Furthermore, it is characterized by having a reflective layer having a triangular cross-sectional shape, located between the concave lens and the glass substrate and approximately on the central axis of the concave lens.

[Effect]

The operation of the present invention will be explained based on FIG. 1.

By arranging a concave lens approximately on the central axis of the light shielding section consisting of the liquid crystal drive section and wiring section of the liquid crystal display element (aligning it with the approximately central axis of the concave lens), the light that enters the light shielding section is directed through the concave lens to its optical path. is bent and guided into the transparent pixel aperture. Therefore, the amount of luminous flux that passes through the transparent pixel opening increases, and the light utilization efficiency of the liquid crystal display element improves. Further, as shown in FIG. 2, by providing a reflective layer having a triangular cross-section at the lower center of the concave lens, light incident on the center of the concave lens can also be guided to the transparent pixel opening.

〔Example〕

Hereinafter, the present invention will be explained in detail based on Examples.

However, the present invention is not limited to the following examples.

[Embodiment 1] FIG. 1 is a sectional view of a liquid crystal display element showing an embodiment of the present invention. In FIG. 1, 11 is a concave lens array;
2 is a common electrode substrate, 13 is a pixel opening, 14 is a light shielding part,
15 is a liquid crystal, 16 is a transparent pixel opening, 17 is a liquid crystal driving section and wiring section, 18 is a transparent glass substrate, and 19 is an incident light beam. In this example, a strip-shaped concave lens array was formed. In the liquid crystal display element, in order to stabilize the characteristics of the driving element, the liquid crystal driving part and the wiring part 17 are covered with a light-shielding film 1.
Covered by 4.

As can be seen from the figure, in the liquid crystal display element of the present invention, the recesses are arranged on the light shielding part so that the substantially central axis of the concave lens is located approximately at the center of the light shielding part.

The optical path of the light incident on the light shielding part is bent by the concave lens, and most of it is guided to the pixel aperture.

Therefore, without being limited by the size of the pixel aperture, it is possible to guide even the light incident on the light shielding part to the transparent pixel aperture, allowing more incident light to pass through the image than when no concave lens is installed. We were able to obtain a bright liquid crystal display element that can be used for display purposes and has high light utilization efficiency.

Here, one method for manufacturing the concave lens array 11 used in this example will be explained. FIG. 3(a) and FIG. 3(b) schematically show the steps for producing a concave lens array. A lens molding resin 31 is uniformly applied on the common electrode substrate 12, and a metal film 32 is selectively formed thereon so as to cover the pixel openings 13 (FIG. 3(a)). Thereafter, wet etching was performed to form a concave shape in the portion of the lens molding resin not covered with the metal film (FIG. 3(b)), and finally the metal film was removed to form a concave lens array 11.

[Example 2] The light incident on the central part of the concave lens has an angle of incidence close to 90'', so the optical path is hardly bent. Therefore, most of the light reaches the light shielding part, and the pixel aperture In other words, by guiding the light passing through the center of the concave lens to the pixel aperture, the light utilization efficiency of the liquid crystal display element can be improved compared to that of the liquid crystal display element shown in Example 1. It can be said that it can be further improved.

FIG. 2 shows a cross-sectional view of a liquid crystal display element according to another embodiment of the present invention in consideration of this point. In this example, a reflective layer having a triangular cross-sectional shape was formed below the concave lens (on the light output side of the concave lens) so that the substantially central axis of the concave lens and the axis of symmetry of the reflective layer substantially coincided. By forming this reflective layer, the optical path of the light that has passed through the center of the concave lens is bent by the reflective layer, allowing almost all of the light to be guided to the pixel aperture, resulting in a bright liquid crystal display with high light utilization efficiency. We were able to obtain a display element.

〔Effect of the invention〕

As explained above, in the liquid crystal display element according to the present invention, by forming a concave lens array and a reflective layer on the light shielding part on the light incident side, it is possible to guide the light incident on the light shielding part to the transparent pixel opening. As a result, the light utilization efficiency of the liquid crystal display element has improved, and it has become possible to obtain bright display images. In particular, by forming a reflective layer at the bottom of the concave lens, it is possible to effectively guide even light incident from an oblique direction to the pixel aperture, thereby achieving further improvement in light utilization efficiency. It can be said that the structure of the display element is particularly effective in increasing the definition of the element.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are diagrams showing one embodiment of the present invention. FIG. 3(a) and FIG. 3(b) are diagrams for explaining one method of manufacturing a concave lens array in Example 1. 11... Concave lens array 12... Common electrode substrate 13... Pixel aperture 14... Light shielding part 15... Liquid crystal 16... Transparent pixel opening 17... Liquid crystal driving part and wiring part 18 ... Transparent glass substrate 19 ... Incident light rays 20 ... Reflection layer 31 ... Lens molding resin 32 ... Metal film or more Applicant Seiko Epson Co., Ltd. Agent Patent attorney Kizoki Ogi 1 person) Rod 11 Figure 2 Calculation 3+”!l(b)

Claims (2)

[Claims] (1) In an active matrix or multi-matrix liquid crystal display element in which a transparent pixel aperture and a light shielding part consisting of a liquid crystal drive part, a wiring part, etc. are arranged regularly, the common pixel electrode of the liquid crystal display element is 1. A liquid crystal display device, characterized in that concave lenses are formed in an array on a glass substrate so that a substantially central axis of the concave lenses coincides with substantially the center of a light shielding portion. (2) The liquid crystal display element according to claim 1, further comprising a reflective layer having a triangular cross-sectional shape and located between the concave lens and the glass substrate and substantially on the central axis of the concave lens.