JPS58169132A - Liquid crystal display - Google Patents

Abstract

PURPOSE:To obtain the effect of uniform visibility, a wide angle of field, and high contrast, by providing a light diffusion element on the side opposite to an irradiating device for parallel light with a liquid crystal panel in-between. CONSTITUTION:The incident angle of the parallel rays incident to a transmission type liquid crystal panel 2 from an irradiating device 1 for parallel light is in the direction where the contrast of the transmitted light is maximized in the panel 2. With the liquid crystal display of such constitution, the parallel rays or nearly parallel rays are made incident to the panel 2 so as to transmit therethrough in the direction where the max. contrast is obtained; therefore, the display of high contrast is inevitably obtained, and further the parallel rays transmitted through the panel 2 are refracted by a concave lens 3 and are diffused as if the rays are radiated from the focus of said lens 3, so that the observers 5a, 5b in the different observation directions are able to observe the same display with the same visibility.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid crystal display device that provides uniform visibility, a wide viewing angle, high contrast, and a high contrast.

Figure 1 is a diagram showing an example of the contrast characteristics of transmitted light of a TN type liquid crystal.
is the polar axis, the angle is - (the normal direction is 1 = υ°) in the latitude direction, the angle ψ is clockwise in the longitude direction, and the arbitrary direction (
The contrast at -0ψJ is determined by equation 1 and is a diagram drawn by connecting four points with equal contrast.

C(-, de): Contrast in the (#, ψ) direction IMAx
(1, p): When the silk J-sleep pressure is changed by 1r.

(#, of the transmitted light intensity in the direction of the ladle force) Maximum value IMIN (town): Change the E4J loading pressure at 9 o'clock.

<1. The higher the minimum value contrast of the transmitted light intensity in the f) direction, the greater the contrast between light and dark, and good visibility can be expected. However, with TN type liquid crystals, as shown in Figure 1, high contrast, that is, good visibility is expected. The range that can be obtained is limited.

(#'' in Figure 1; 20°t = 210°~240'
As an all-LCD display device with a narrow high-contrast area, in a display device irradiated with diffused light in which light enters from various directions, the contrast varies greatly depending on the viewing direction, and excellent 4Mg properties can be obtained. The drawback was that the range, or viewing angle, was narrow.

The present invention aims to improve the above-mentioned drawbacks.

An example of this is shown in FIG.

Liquid crystal display in Figure 12 - 1 & position is parallel %L< is a parallel light irradiation device that irradiates parallel light that is close to parallel, and the transmitted light is changed by 9J degrees depending on the applied voltage.0 characters.

From a transmissive desire crystal panel (2) that displays figures, etc., and a concave lens (3) that is a light diffusing element provided on the opposite side of the parallel light irradiation device across the liquid crystal panel (2). It is configured. Here, the angle of incidence of the parallel rays entering the transmission-forming 6 panel (2) from the parallel light irradiation device is the direction in which the contrast of the transmitted light is maximized in the transmission-type Soteki panel (2). do. (For example, in Figure 11, −ζ
Let the angle M7Lt - the angle of incidence be such that the light is transmitted between 20° ψ = 210° and 2400°. ] In the liquid crystal display device of FIG. 2 having such a configuration, parallel light or nearly parallel light is incident on the transmissive liquid crystal panel (2) in such a way that it is transmitted in a direction that provides a large contrast of IMk and Rk. To be there.

Naturally, a display with high contrast is obtained, and the parallel light that passes through the Zaraani Station Transparent-type Sengoku Crystal Panel + 21 T- is transmitted through the concave lens (
3) and is diffused as if it were radiated from the focal point of the concave lens (3), so the observation direction is different as shown in FIG. (5aJ (5b
It becomes possible for both parties to observe the same display under the same oaaa characteristics.

FIG. 3 shows an embodiment of the present invention different from that shown in FIG. It has a similar structure. The liquid crystal and display device based on this third factor are manufactured in the same way as the liquid crystal display device shown in FIG.
The first parallel light I encountered.

The diffusive light transmission & 141 K allows the light to be diffused and submerged, and the same effect as explained in FIG. 2 of W#J can be obtained.

In the liquid crystal display device of the present invention described above with reference to FIGS. 2 and 3, the angle of incidence t of light on the liquid crystal panel is the same as the direction in which the contrast of transmitted light is maximum! and parallel or nearly parallel rays are incident, and in the case of parallel or nearly parallel rays, any direction other than the extension of the rays is parallel rays. The same visibility is achieved regardless of the direction by the concave lens of the light diffusion element and the diffusion effect of the diffusive light transmitting plate, resulting in uniform visibility and a wide viewing angle.

This is a display device that provides a high contrast effect.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of custom-made contrast of a TN type liquid crystal according to the present invention. Figure 2. FIG. 3 is a diagram showing an embodiment of the present invention. In the figure, the mountain is the parallel light irradiation device, (2) is the transmissive liquid crystal panel, and +31i4J is the optical sales promotion unit. Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent Kuzu ＃ times - Figure 1 Figure 2 Figure 3 177-

Claims (3)

[Claims] (1) Consisting of a parallel light irradiation device that emits parallel light, a transmissive liquid crystal panel, and a light diffusing element installed on a plane opposite to the parallel light irradiation device across the liquid crystal panel.
Characteristic liquid crystal display device. (2) It is assumed that the light diffusing element is a concave lens. A liquid crystal display device as described in the claims. (3) A liquid crystal display device according to claim 5, characterized in that the light diffusing element is a diffusive light transmitting plate.