JPH11271772A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To observe information while effectively using luminous flux even if external light is insufficient by properly setting the constitution of a lighting means. SOLUTION: The curvature, arrangement, etc., of the incidence surface 12 and surface 3 of a light source means 1 and an optical member 2 are properly set so that the luminous flux from the light source means 1 is made incident on the light incidence surface 12 of the optical member 2, totally reflected by the surface 3 to pass through a surface 4 and travel to an LCD 5 and the reflected light from the LCD 5 passes through the surfaces 4 and 3. When the external light is dark, the light source means 1 turns on according to the signal from an optical sensor and pieces 6 and 9 of luminous flux (divergent light) from the light source means 1 are made incident on the light incidence surface 12 of the optical member 2, are totally reflected by the surface 3, and become convergent light (or luminous flux close to parallel light) and emit from the surface 4 to irradiate the LCD 5. The luminous flux reflected by the LCD 5 pass through the surfaces 4 and 3 as shown pieces 8 and 11 of luminous flux to exit to an observation side. Consequently, image information based upon the LCD 5 is observed by using the luminous flux from the light source means 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention illuminates a reflection type liquid crystal display device (LCD) with external light or a light beam from illumination means.
The present invention relates to a liquid crystal display device having a built-in illumination means suitable for observing image information based on a light beam light-modulated by the liquid crystal display element.

[0002]

2. Description of the Related Art In recent years, various liquid crystal display devices using a reflection type liquid crystal display element (reflection type LCD) have been proposed as small display devices.

[0003] Reflective LCDs are premised on irradiating with external light due to their characteristics. For this reason, there has been no liquid crystal display device that illuminates a reflective LCD with a built-in illuminating means and observes image information based on the liquid crystal display element.

[0004]

A liquid crystal display device using a reflection type LCD is premised on irradiation by external light. Therefore, when the external light has sufficient brightness, there is no problem in observing the image information based on the liquid crystal display element.

[0005] However, when the brightness of the external light is insufficient, an illuminating means for illuminating the liquid crystal display element is required. However, if the illuminating means is simply built into the observation device, the entire device becomes large.

According to the present invention, even if external light is insufficient for image information based on a reflection type liquid crystal display element, the size of the entire apparatus can be reduced by appropriately setting the configuration of the illuminating means. It is another object of the present invention to provide a liquid crystal display device that allows observation while using light beams effectively.

[0007]

According to the present invention, there is provided a liquid crystal display device comprising: (1-1) a light incident surface on which a light beam enters, a light beam from the light incident surface totally reflected, and a light from outside light incident. An optical member integrally formed with a curved surface to be emitted, an emission surface for emitting a light beam from the curved surface, a reflection type liquid crystal display element arranged to face the emission surface side and inclined with respect to the emission surface, and the light Light source means disposed opposite to the incident surface side, the light flux from the external light irradiates the liquid crystal display element through the curved surface and the emission surface of the optical member, and the light flux from the light source means The light enters from the light incident surface, is totally reflected on the curved surface, irradiates the liquid crystal display element through the exit surface, and guides the reflected light from the liquid crystal display element in the observation direction through the exit surface and the curved surface. It is characterized in that image information based on a liquid crystal display element is observed.

In particular, (1-1-1) a light shielding member is provided on the light incident surface of the optical member on the liquid crystal display element side.

(1-2) An observation device having a point light source, an optical member having a light incident surface, a parabolic surface, and a light exit surface, and a reflection type liquid crystal display element, wherein a light beam from the point light source is Light incident on the paraboloid from the incident surface of the optical member is totally reflected, and light reflected by the liquid crystal display element is transmitted through the paraboloid,
The liquid crystal display device is characterized in that the incident surface is inclined so as to descend from the parabolic end toward the point light source.

[0010] In the other configuration (1-1) or (1-2), (1-2-1) a driving member for driving the light source means by an external operation is provided.

(1-2-2) A light sensor for detecting the brightness of external light is provided, and the light source means is driven based on a signal from the light sensor. And so on.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic view of a main part of a first embodiment of an observation apparatus according to the present invention. In the figure, 5 is a reflective liquid crystal display (LCD), and 2 is a transparent optical member. The surface 4 on the LCD 5 side (inside) constituting the optical member 2 is an emission surface and is formed of a flat surface, and the outer surface 3 is formed of a spherical surface, an aspherical surface, a paraboloid, an elliptical surface, and a rotationally asymmetric surface.

Reference numeral 12 denotes a light incident surface of the optical member 2, which has a flat surface, a spherical surface, an aspherical surface, and the like. Surface 4 of optical member 2
And the surface 5a of the LCD 5 is inclined by the angle θ. That is, one end of the optical member 2 and one end of the liquid crystal display element 5 are brought into contact with each other, and the other end (the light source 1 side) is separated from each other.

Reference numeral 1 denotes light source means, which comprises a point light source, a line light source, a surface light source, a light emitting diode, a light emitting diode array, and the like.

Reference numeral 14 denotes a spherical surface, a cylindrical surface, an aspherical surface,
This is an auxiliary mirror using internal reflection such as an elliptical surface. Of the light beams emitted from the light source means 1, the light beam emitted to the opposite side to the optical member 3 is reflected, and the light incident surface 12 of the optical member 3 is reflected.
The light is guided.

Reference numeral 13 denotes a light-shielding plate, which is a light beam from the light source means 1 and which is directly incident on the surface 4 of the light beam incident from the light incident surface 4 of the optical member 3 so that a light beam reflected or transmitted by the surface 4 is not generated. I have to.

Thus, it is possible to prevent light other than the reflected light from the LCD 5 from being emitted in the observation direction and becoming flare light, thereby deteriorating the observation image quality of image information based on the LCD 5.

In this embodiment, the brightness of the external light is detected by an optical sensor provided in the apparatus, and the light source means 1 is driven based on a signal from the external sensor. When the external light is bright, the light source means 1 is turned off. At this time, the external light enters from the surface 3 and passes through the surface 4 to illuminate the LCD 5.

Light beams that have been slightly scattered and reflected at, for example, the regions 7 and 10 on the reflection surface of the LCD 5 are emitted almost reversibly as light beams 8 and 11 in the observation direction. This gives LC
The image information based on D5 is observed by external light.

On the other hand, when the external light is dark, the light source means 1 is turned on based on a signal from the optical sensor, and the luminous fluxes (divergent light) 6, 9 from the light source means 1 enter the light incident surface 12 of the optical member 2. Then, the light is totally reflected by the surface 3 to become convergent light (or a light flux close to parallel light) and is emitted from the surface 4 to irradiate the LCD 5.

The light beam reflected by the LCD 5 passes through the surfaces 4 and 3 and exits to the observation side as light beams 8 and 11. Thus, image information based on the LCD 5 is observed using the light beam from the light source 1.

In the present embodiment, a light beam from the light source means 1 is incident on the light incident surface 12 of the optical member 2, is totally reflected by the surface 3, passes through the surface 4, and is directed to the LCD 5, while the light reflected by the LCD 5 is The curvature, arrangement, and the like of the light source means 1 and the entrance surface 12 and the surface 3 of the optical member 2 are appropriately set so as to pass through the surfaces 4 and 3.

In the present embodiment, the operation of the light source means 1 may be manually performed using a switch or the like without being based on a signal from the optical sensor.

[0024]

As described above, according to the present invention, the image information based on the reflection type liquid crystal display device can be obtained by appropriately setting the configuration of the illumination means even when external light is insufficient. In addition, a liquid crystal display device that can be observed while miniaturizing the entire device and effectively using a light beam can be achieved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a main part of a first embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light source means 2 Optical member 3 Curved surface 4 Emission surface 5 Reflection type liquid crystal display element 6, 8, 9, 11 Light flux 7, 10 Area 12 Light incidence surface 13 Shield plate

Continuation of the front page (51) Int.Cl. ⁶ identification code FI G09F 9/00 332 G09F 9/00 332F 332D 335 335Z 336 336C 366 366G

Claims (5)

[Claims] 1. A light incident surface on which a light beam enters, a curved surface for totally reflecting the light beam from the light incident surface and receiving light from outside light, and an exit surface for emitting a light beam from the curved surface are integrally formed. Having an optical member, a reflection-type liquid crystal display element disposed to be inclined with respect to the exit surface, facing the exit surface, and light source means disposed to be opposed to the light incident surface. Irradiates the liquid crystal display element through the curved surface and the exit surface of the optical member, and the light beam from the light source means enters from the light incident surface of the optical member, is totally reflected by the curved surface, and passes through the exit surface. And irradiates the liquid crystal display element with light, and guides reflected light from the liquid crystal display element to the observation direction through the exit surface and the curved surface to observe image information based on the liquid crystal display element. Liquid crystal display. 2. The liquid crystal display device according to claim 1, wherein a light blocking member is provided on a side of the liquid crystal display element on a light incident surface of the optical member. 3. An observation device having a point light source, an optical member having a light incident surface, a parabolic surface, and a light exit surface, and a reflection type liquid crystal display element, wherein a light flux from the point light source is transmitted to the optical member. The incident surface of the liquid crystal display element is moved from the end of the parabolic surface to the point light source such that light incident on the parabolic surface from the incident surface is totally reflected, and light reflected by the liquid crystal display element is transmitted through the parabolic surface. A liquid crystal display device, wherein the liquid crystal display device is arranged so as to be inclined downward toward. 4. The liquid crystal display device according to claim 1, further comprising a driving member for driving said light source means by an external operation. 5. The liquid crystal according to claim 1, further comprising an optical sensor for detecting the brightness of external light, wherein said light source is driven based on a signal from said optical sensor. Display device.