JP7197990B2 - reflective liquid crystal display - Google Patents

Description

The present invention relates to a reflective liquid crystal display device.

In recent years, miniaturization, especially low profile, of reflective liquid crystal display devices has become a necessary technology for improving the visibility and light collection efficiency of the liquid crystal display panel by bringing the distance between the observer and the liquid crystal display panel closer. and the demand is getting stronger. In order to satisfy this demand, a reflective liquid crystal display device using a transparent member (prism) as part of the illumination optical system of the liquid crystal display panel has been proposed.

FIG. 2 is a longitudinal sectional view showing a conventional reflective liquid crystal display device. A conventional reflective liquid crystal display device has the following configuration. A reflective liquid crystal display panel 2 is arranged on the same surface of the circuit board 1 with its image display surface facing upward, and a light source 3 is arranged adjacent thereto with its light exit surface facing upward. A first housing 13 is arranged above and around the reflective liquid crystal display panel 2 so as to cover the reflective liquid crystal display panel 2, and above and around the light source 3 is arranged so as to cover the light source 3. , a second housing 14 is arranged. The inner surface of the second housing 14 is provided with a first reflecting surface for guiding the light emitted from the light source 3 toward the plate-shaped polarizing beam splitter 6 arranged above the reflective liquid crystal display panel 2. 14a and a second reflective surface 14b are provided. On the optical path from the second reflecting surface 14b to the polarizing beam splitter 6, there are a diffuser plate 4 for diffusing light and one of two types of linearly polarized light whose polarization axes are orthogonal to each other (hereinafter referred to as P-wave). ) is arranged thereon. The polarizing beam splitter 6 has a light transmissive reflecting surface that reflects the P wave and transmits the other linearly polarized light (hereinafter referred to as the S wave) whose polarization axis is orthogonal to the P wave. The tilt angle is determined so that the P-wave thus generated is vertically incident on the image display surface of the reflective liquid crystal display panel 2 , and is held by the first housing 13 .

The conventional reflective liquid crystal display device also includes a first transparent member 9 and a second transparent member 10 for refracting light emitted from the light source 3 . The first transparent member 9 has a first surface 9a on which the P wave emitted from the polarizing plate 5 is incident, a second surface 9b facing the light transmitting and reflecting surface of the polarizing beam splitter 6, and a reflective liquid crystal display. It has a side surface composed of a third surface 9c facing the image display surface of the panel 2, and two bottom surfaces (not shown) parallel to each other and connected to the side surfaces at right angles. It is a right-angled triangular prism-shaped transparent member in which the third surface 9c and the surface 9a are perpendicular to each other. The second transparent member 10 has a first surface 10a facing the side surface of the first housing 13, a second surface 10b facing the light transmitting/reflecting surface of the polarization beam splitter 6, and an observer's eye 15. A transparent member in the shape of a right-angled triangular prism having side surfaces composed of a third surface 10c from which light is emitted, and two parallel bottom surfaces (not shown) connected to the side surfaces at right angles. be. The first transparent member 9 is arranged above the reflective liquid crystal display panel 2 so that the third surface 9 c is close to the image display surface of the reflective liquid crystal display panel 2 . The second transparent member 10 is arranged above the first transparent member 9 so that the second surface 10b faces the second surface 9b of the first transparent member 9 with the polarizing beam splitter 6 interposed therebetween. ing. The first transparent member 9 and the second transparent member 10 are made of, for example, polycarbonate having a refractive index of about 1.6, and have the same shape.

A first refractive film 7 is formed on the second surface 9b of the first transparent member 9, and a second refractive film 8 is formed on the second surface 10b of the second transparent member 10. there is The first refraction film 7 and the second refraction film 8 are, for example, films of titanium oxide having a light refractive index of 2.5 to 2.72 formed by a sputtering method, a vapor deposition method, a coating method, or the like. However, the first refractive film 7 and the second refractive film 8 are not essential and may be omitted.

A lower air layer 11a is provided between the first refractive film 7 and the polarizing beam splitter 6, and an upper air layer 11b is provided between the second refractive film 8 and the polarizing beam splitter 6. there is However, the lower air layer 11a and the upper air layer 11b may be omitted.

An air layer 12 is provided between the third surface 9 c of the first transparent member 9 and the image display surface of the reflective liquid crystal display panel 2 . However, the air layer 12 may be omitted.

The diffuser plate 4 and the polarizing plate 5 are laminated on each other and arranged at a position facing the first surface 9 a of the first transparent member 9 . The light exit surface of the diffuser plate 4 and the light exit surface of the diffuser plate 5 are arranged parallel to the first surface 9 a of the first transparent member 9 .

A principal luminous flux of light emitted from the light source 3 follows a path indicated by an arrow in FIG. A principal luminous flux of light emitted from the image display surface of the reflective liquid crystal display panel 2 follows a path indicated by an arrow in FIG.

The reflective liquid crystal display panel 2 is configured so that the P wave passes through the liquid crystal as it is when the power is turned off. The reflected P wave is vertically reflected by a reflective element (reflective electrode, etc.) provided on the back side of the panel 2 and travels toward the polarizing beam splitter 6 again. The polarizing beam splitter 6 is arranged so as not to transmit the P wave, and blocks the P wave reflected by the reflective liquid crystal display panel 2, resulting in a black display state when the power is off.

On the other hand, in the reflective liquid crystal display panel 2, when the power is on, the liquid crystal converts the P wave into the S wave, and the S wave is reflected on the back side of the reflective liquid crystal display panel 2 in the same way as the P wave, and is converted into a polarizing beam splitter. Proceed to 6. Since the polarizing beam splitter 6 is arranged to transmit the S wave, the display is white when the power is on.

The above process is performed for each pixel of the reflective liquid crystal display panel 2, and the S wave that has passed through the polarization beam splitter 6 is incident on the observer's eye 15 and viewed as an image.

A conventional reflective liquid crystal display device in which a transparent member for refracting light is arranged between a reflective liquid crystal display panel 2 and a polarizing beam splitter 6 as shown in FIG. disclosed.

JP 2014-209225 A

In the conventional reflective liquid crystal display device shown in FIG. 2, since the diffuser plate 4 is arranged parallel to the first surface 9a of the first transparent member 9, light is emitted from the diffuser plate 4. The emitted light uniformly enters the first surface 9 a of the first transparent member 9 . However, depending on the design of the optical system, the uniform incidence of light on the first surface 9a of the first transparent member 9 results in the light emitted from the image display surface of the reflective liquid crystal display panel 2. may be uneven and degrade image quality (e.g. dark lines appear in the image).

SUMMARY OF THE INVENTION It is an object of the present invention to provide a reflective liquid crystal display device capable of improving image quality.

A light source, a reflective liquid crystal display panel, a diffusion plate for diffusing light emitted from the light source, and one of two types of linearly polarized light having orthogonal polarization axes contained in the light emitted from the light source. a polarizing plate that transmits only polarized light; and the one linearly polarized light that has passed through the polarizing plate is reflected toward the image display surface of the reflective liquid crystal display panel, and from the image display surface of the reflective liquid crystal display panel. A polarizing beam splitter having a light transmitting/reflecting surface that transmits the other linearly polarized light whose polarization axis is orthogonal to the emitted linearly polarized light, and the image display surface of the reflective liquid crystal display panel and the polarizing beam splitter. and a transparent member having a higher refractive index of light than that of the air layer, the reflective liquid crystal display device being disposed between the light transmissive and reflective surface, wherein the diffusion plate comprises the transparent The diffusion plate is arranged at a position facing the light incident surface on which the one linearly polarized light transmitted through the polarizing plate is incident on the surface of the member, and the light output surface of the diffuser plate faces the light incident surface of the transparent member. A tilted reflective liquid crystal display device is provided.

The light exit surface of the diffuser plate is such that a region of the light incident surface of the transparent member facing a region adjacent to the polarizing beam splitter corresponds to the reflective liquid crystal display panel of the light incident surface of the transparent member. The reflective liquid crystal display device may be inclined so as to be further away from the light incident surface of the transparent member than the area facing the area adjacent to the transparent member.

The reflective liquid crystal display, wherein the polarizing plate is arranged at a position facing the light incident surface of the transparent member, and the light emitting surface of the polarizing plate is inclined with respect to the light incident surface of the transparent member. It may be a device.

The light emitting surface of the diffusion plate and the light emitting surface of the polarizing plate may be inclined in the same direction with respect to the light incident surface of the transparent member.

The diffuser plate is arranged at a position facing the light incident surface of the polarizing plate, and the light emitted from the light emitting surface of the diffuser plate is incident on the light incident surface of the polarizing plate. It may be a display device.

According to the present invention, it is possible to provide a reflective liquid crystal display device capable of improving image quality.

1 is a longitudinal sectional view showing an embodiment of a reflective liquid crystal display device according to the present invention; Longitudinal sectional view showing a conventional reflective liquid crystal display device

FIG. 1 is a longitudinal sectional view showing one embodiment of a reflective liquid crystal display device according to the present invention. One embodiment of the reflective liquid crystal display device according to the present invention has the following configuration. A reflective liquid crystal display panel 2 is arranged on the same surface of the circuit board 1 with its image display surface facing upward, and a light source 3 is arranged adjacent thereto with its light exit surface facing upward. A first housing 13 is arranged above and around the reflective liquid crystal display panel 2 so as to cover the reflective liquid crystal display panel 2, and above and around the light source 3 is arranged so as to cover the light source 3. , a second housing 14 is arranged. The inner surface of the second housing 14 is provided with a first reflecting surface for guiding the light emitted from the light source 3 toward the plate-shaped polarizing beam splitter 6 arranged above the reflective liquid crystal display panel 2. 14a is provided. On the optical path from the first reflecting surface 14a to the polarizing beam splitter 6, there are a diffuser plate 4 for diffusing light and one of two types of linearly polarized light whose polarization axes are orthogonal to each other (hereinafter referred to as P-wave). ) is arranged thereon. The polarizing beam splitter 6 has a light transmissive reflecting surface that reflects the P wave and transmits the other linearly polarized light (hereinafter referred to as the S wave) whose polarization axis is orthogonal to the P wave. The tilt angle is determined so that the P-wave thus generated is vertically incident on the image display surface of the reflective liquid crystal display panel 2 , and is held by the first housing 13 .

The reflective liquid crystal display device of this embodiment includes a first transparent member 9 and a second transparent member 10 for refracting light emitted from the light source 3 . The first transparent member 9 has a first surface 9a on which the P wave emitted from the polarizing plate 5 is incident, a second surface 9b facing the light transmitting and reflecting surface of the polarizing beam splitter 6, and a reflective liquid crystal display. A triangular prism-shaped transparent member having a side surface composed of a third surface 9c facing the image display surface of the panel 2, and two parallel bottom surfaces (not shown) connected to the side surfaces at right angles. be. The angle formed by the first surface 9a and the third surface 9c of the first transparent member 9 is an acute angle. The second transparent member 10 has a first surface 10a facing the side surface of the first housing 13, a second surface 10b facing the light transmitting/reflecting surface of the polarization beam splitter 6, and an observer's eye 15. A third surface 10c through which light is emitted toward the light, a fourth surface 10d facing the outer peripheral portion of the reflective liquid crystal display panel 2, and a fifth surface 10e adjacent to the polarizing plate 5. It is a trapezoidal columnar transparent member having side surfaces and two parallel bottom surfaces (not shown) connected to the side surfaces at right angles. The first surface 10a and the fifth surface 10e of the second transparent member 10 are parallel to each other, and the third surface 10c and the fourth surface 10d are parallel to each other. The first transparent member 9 is arranged above the reflective liquid crystal display panel 2 so that the third surface 9 c is close to the image display surface of the reflective liquid crystal display panel 2 . The second transparent member 10 is arranged above the first transparent member 9 so that the second surface 10b faces the second surface 9b of the first transparent member 9 with the polarizing beam splitter 6 interposed therebetween. ing. The first transparent member 9 and the second transparent member 10 are made of polycarbonate having a light refractive index of about 1.6, for example.

A first reflecting surface 14 a is provided in a region of the inner surface of the second housing 14 that faces the light exit surface of the light source 3 . The angle of the first reflecting surface 14 a is set so as to reflect the main luminous flux of the light emitted from the light source 3 toward the diffusion plate 4 . The first reflective surface 14a is configured as a reflective surface by, for example, forming the second housing 14 with a white resin or placing a reflective sheet or the like on the inner surface of the second housing 14. there is A region of the inner surface of the second housing 14 excluding the first reflective surface 14a may be a reflective surface in the same way, but may not be a reflective surface.

The diffusing plate 4 is laminated on the light incident surface of the polarizing plate 5 and arranged in a position facing the first surface 9 a of the first transparent member 9 integrally with the polarizing plate 5 . The diffusion plate 4 and the deflection plate 5 are held by the second housing 14 in a state in which the respective light exit surfaces are inclined with respect to the first surface 9 a of the first transparent member 9 . The diffusion plate 4 and the deflection plate 5 have their upper ends (the ends adjacent to the second surface 9b of the first transparent member 9) and the lower ends (the third surface 9c of the first transparent member 9). and the edge adjacent to the side), the first surface 9a of the first transparent member 9 and the polarizing plate 5 An air layer 16 whose thickness continuously changes is formed between the . The thickness of the air layer 16 changes continuously according to the inclinations of the diffusion plate 4 and the polarizing plate 5 so that the upper end side thereof is relatively larger and the lower end side thereof is relatively smaller. Accordingly, the optical path length between the polarizing plate 5 and the first surface 9a of the first transparent member 9 also changes. Light incident on the first surface 9a of the first transparent member 9 from the polarizing plate 5 side in the portion where the optical path length is relatively large (long) than in the portion where the optical path length is relatively small (short) is highly diffusible. The thickness of the air layer 16 is, for example, 1 mm or more.

The angle of the diffuser plate 4 and the polarizing plate 5 with respect to the first surface 9a of the first transparent member 9 is such that the P wave entering the inside of the first transparent member 9 from the first surface 9a of the first transparent member 9 is is set to be totally reflected at the interface between the third surface 9c of the first transparent member 9 and the reflective liquid crystal display panel 2 and an air layer (not shown). Conditions for total reflection are, for example, nA for the refractive index of the air layer interposed between the third surface 9c of the first transparent member 9 and the reflective liquid crystal display panel 2, and nA for the refractive index of the first transparent member 9. is nB, and the incident angle of the P wave incident on the third surface 9c from the first surface 9a side of the first transparent member 9 to the third surface 9c (the angle with respect to the normal to the third surface 9c) is α, Snell is determined based on the formula "sinα=nA/nB" derived using the law of In other words, the condition for total reflection is that the incident angle of the P wave incident on the third surface 9c from the first surface 9a side of the first transparent member 9 is larger than θ (critical angle) in the formula; becomes.

An air layer (not shown) having a predetermined thickness is interposed between the second surface 9b of the first transparent member 9 and the second surface 10b of the second transparent member 10. A flat polarizing beam splitter 6 is arranged in the middle to divide the air layer in its thickness direction into a lower air layer (not shown) and an upper air layer (not shown). The lower air layer is interposed between the light transmissive and reflective surface of the polarizing beam splitter 6 and the second surface 9b of the first transparent member 9, and the upper air layer is interposed between the light transmissive and reflective surface of the polarizing beam splitter 6 and the second surface 9b. It is interposed between the second surface 10b of the second transparent member 10 and the second surface 10b. This configuration is similar to that of the conventional reflective liquid crystal display device shown in FIG. However, the lower air layer and the upper air layer are not essential, and one or both of them may be omitted as necessary. When the lower air layer and the upper air layer are omitted, the light transmitting/reflecting surface of the polarizing beam splitter 6 and the second surface 9b of the first transparent member 9 are in close contact with each other. The second surfaces 10b of the second transparent member 10 may be in close contact with each other, or a transparent adhesive or the like may be interposed therebetween.

The angle of the second surface 9b of the first transparent member 9 is such that the P wave that is totally reflected by the third surface 9c of the first transparent member 9 and is incident on the second surface 9b of the first transparent member 9 is set at an angle such that the main luminous flux of .lambda. Conditions for not total reflection are, for example, the refractive index of the lower air layer as nA, the refractive index of the first transparent member 9 as nB, and light incident on the second surface 9b from the third surface 9c side of the first transparent member 9. is determined based on the formula "sin θ=nA/nB" derived using Snell's law, where θ is the incident angle of the P wave (the angle with respect to the normal to the second surface 9b). In other words, the conditions for preventing total reflection are that the incident angle of the P wave incident on the second surface 9b from the third surface 9c side of the first transparent member 9 is smaller than θ (critical angle) in the formula; becomes.

However, the light enters from the first surface 9a of the first transparent member 9 and directly enters the second surface of the first transparent member 9 without entering the third surface 9c of the first transparent member 9. This does not apply to the P-wave principal beam incident on 9b. That is, the angle of the second surface 9b of the first transparent member 9 is such that the P wave incident on the second surface 9b from the first surface 9a side of the first transparent member 9 is The light is totally reflected at the interface with the air layer (not shown), travels inside the first transparent member 9 toward the third surface 9c, and reaches the interface between the third surface 9c and the air layer (not shown). , and travels through the interior of the first transparent member 9 toward the second surface 9b. It is also set at an angle that spreads over the entire display surface.

In this embodiment, the main luminous flux of light emitted from the light source 3 is reflected by the first reflecting surface 14a provided on the inner surface of the second housing 14, as indicated by the arrow in FIG. Incident on the diffuser plate 4 . The light incident on the diffusion plate 4 is diffused by the diffusion plate 4, passes through the polarizing plate 5, becomes a P wave, passes through the air layer 16, and enters the first surface 9a of the first transparent member 9. do. The P wave incident on the first surface 9 a passes through the inside of the first transparent member 9 and enters the third surface 9 c of the first transparent member 9 . The P wave incident on the third surface 9c is totally reflected toward the second surface 9b of the first transparent member 9 at the interface between the third surface 9c and an air layer (not shown), passes through the transparent member 9 and enters the second surface 9 b of the first transparent member 9 . The P wave incident on the second surface 9 b passes through the second surface 9 b and is incident on the light transmitting/reflecting surface of the polarizing beam splitter 6 . The P-wave incident on the light transmitting/reflecting surface of the polarizing beam splitter 6 is reflected by the light transmitting/reflecting surface in a direction perpendicular to the image display surface of the reflective liquid crystal display panel 2, and passes through the second light of the first transparent member 9. 9 b and the inside of the first transparent member 9 to enter the third surface 9 c of the first transparent member 9 . The P wave incident on the third surface 9c passes through the air layer without being refracted at the interface between the third surface 9c and the air layer (not shown) to reach the image display surface of the reflective liquid crystal display panel 2. , where it becomes image light (mixed light of P wave and S wave) and is reflected toward the polarizing beam splitter 6 side. The reflected image light passes through the air layer, enters the third surface 9c of the first transparent member 9, and is not refracted at the interface between the third surface 9c and the air layer. It passes through the transparent member 9 and enters the second surface 9 b of the first transparent member 9 . The image light incident on the second surface 9 b passes through the second surface 9 b and is incident on the light transmission/reflection surface of the polarization beam splitter 6 . The S wave contained in the image light incident on the light transmissive and reflective surface of the polarizing beam splitter 6 passes through the light transmissive and reflective surface of the polarizing beam splitter 6 and enters the second surface 10 b of the second transparent member 10 . The S wave incident on the second surface 10 b passes through the second surface 10 b and the inside of the second transparent member 10 and enters the third surface 10 c of the second transparent member 10 . The S wave incident on the third surface 10c is not refracted at the interface between the third surface 10c and the outside world (air layer), is emitted from the second transparent member 10 to the outside world, and reaches the observer's eye 15. and is viewed as an image.

Note that the arrows indicating the optical paths in FIG. 1 only conceptually indicate the optical paths, and do not necessarily match the actual optical paths. Further, the refraction of light occurring at the interface between the polarizing plate 5 and the air layer 16, the interface between the first surface 9a of the first transparent member 9 and the air layer 16, the interior of the reflective liquid crystal display panel 2, etc. , is neglected for convenience, but in practice, the optical system is designed with such refraction of light taken into consideration.

In this embodiment, the diffusion plate 4 and the polarizing plate 5 are inclined with respect to the first surface 9 a of the first transparent member 9 . Compared to the case of arranging parallel to one surface 9a, the thickness of the gap (air layer 16) between the polarizing plate 5 and the first surface 9a of the first transparent member 9 is partially large. Since the optical path is lengthened in the portion where the gap is partially enlarged, the diffusibility of the light emitted from the polarizing plate 5 and incident on the first surface 9a of the first transparent member 9 is enhanced. As a result, uneven brightness of light emitted from the image display surface of the reflective liquid crystal display panel 2 is reduced, and image quality is improved. This effect can also be obtained in a similar manner, for example, when only the diffuser plate 4 is inclined with respect to the first surface 9a of the first transparent member 9. FIG. However, this effect is higher when both the diffusion plate 4 and the polarizing plate 5 are inclined with respect to the first surface 9a of the first transparent member 9 as in this embodiment.

In the above embodiment, the method of irradiating the light from the light source 3 to the polarizing beam splitter 6 side is not limited to the method using the first reflecting surface 14a provided on the inner surface of the second housing 14. For example, A method of interposing a light guide plate between the light emitting surface of the light source 3 and the light incident surface of the polarizing plate 5, or a method of placing the light emitting surface of the light source 3 by a diffusion plate so that the light of the light source 3 is directly irradiated to the diffusion plate 4. Various methods can be selected, such as a method of arranging them so as to face the light incident surface of 4 . Further, the diffuser plate 4 can be omitted when sufficient light diffusibility is ensured. Also, the light source 3 can be mounted not on the circuit board 1 but on another board composed of FPC or the like.

A light absorbing portion that absorbs unnecessary light may be formed in the regions of the surfaces of the first transparent member 9 and the second transparent member 10 excluding the optical surfaces by coloring with a black member or the like. .

On the surfaces of the second surface 9b of the first transparent member 9 and the second surface 10b of the second transparent member 10, light is directed away from the direction of perpendicular incidence on the light transmission/reflection surface of the polarizing beam splitter 6. A refracting film may be formed to refract the light. In this case, the refractive index and thickness of the refracting film are appropriately selected in consideration of how light is to be refracted and the light transmittance. It is preferable to have

The angle formed by the first surface 9a and the third surface 9c of the first transparent member 9 may be a right angle (90°) as in the conventional reflective liquid crystal display device shown in FIG. .

The first transparent member 9 and the second transparent member 10 may have different light refractive indices.

The first transparent member 9 and the second transparent member 10 may have the same shape as each other.

The second transparent member 10 is not essential and may be omitted.

The first housing 13 and the second housing 14 may be made of black resin or the like that absorbs unnecessary light generated inside them.

The first housing 13 and the second housing 14 may be configured integrally with each other.

An air layer is provided between the second surface 9b of the first transparent member 9 and the polarizing beam splitter 6 and between the second surface 10b of the second transparent member 10 and the polarizing beam splitter 6. It doesn't have to be.

The diffuser plate 4 and the polarizing plate 5 may not be laminated together.

The diffusion plate 4 may be arranged between the polarizing plate 5 and the first surface 9 a of the first transparent member 9 . However, it is optically desirable that the diffusion plate 4 is arranged on the light incident surface side of the polarizing plate 5 as shown in FIG.

Only one of the diffusion plate 4 and the polarizing plate 5 may be inclined with respect to the first surface 9 a of the first transparent member 9 .

Diffusion plate 4 and polarizing plate 5 may be tilted in a direction different from the direction shown in FIG. Also, the diffusion plate 4 and the polarizing plate 5 may be inclined in different directions. However, the diffusion plate 4 and the polarizing plate 5 are preferably inclined in the same direction as shown in FIG. 1 in order to control the luminance distribution of light (easier control). In any case, the directions in which the diffusion plate 4 and the polarizing plate 5 are tilted are appropriately determined so as to reduce uneven brightness of the image.

The air layer 16 provided between the first surface 9a of the first transparent member 9 and the polarizing plate 5 may be omitted. In that case, a transparent resin or the like may be interposed between the first surface 9 a of the first transparent member 9 and the polarizing plate 5 .

An optical sheet such as a prism sheet is arranged between the diffusion plate 4 and the polarizing plate 5, at a position facing the light incident surface of the diffusion plate 4, or at a position facing the light exit surface of the polarizing plate 5. Also good. In that case, the optical sheet may be inclined with respect to the first surface 9 a of the first transparent member 9 in the same manner as the diffusion plate 4 and the polarizing plate 5 .

The third surface 9c of the first transparent member 9 and the image display surface of the reflective liquid crystal display panel 2 may or may not be interposed therebetween.

An air layer may or may not be interposed between the first surface 10 a of the second transparent member 10 and the side surface of the housing 14 . If an air layer exists between the first surface 10a of the second transparent member 10 and the side surface of the housing 14, part of the stray light can be confined in the air layer (gap). It becomes possible.

REFERENCE SIGNS LIST 1 circuit board 2 reflective liquid crystal display panel 3 light source 4 diffusion plate 5 polarizing plate 6 polarizing beam splitter 9 first transparent member 9a first surface 9b second surface 9c third surface 10 second transparent member 10a th First surface 10b Second surface 10c Third surface 10d Fourth surface 10e Fifth surface 11a Lower air layer 11b Upper air layer 12 Air layer 13 First housing 14 Second housing 14a First surface Reflective surface 14b Second reflective surface 15 Observer's eye 16 Air layer

Claims (2)

a light source;
a reflective liquid crystal display panel;
a diffusion plate that diffuses the light emitted from the light source;
a polarizing plate that transmits only one linearly polarized light of two types of linearly polarized light whose polarization axes are orthogonal to each other contained in the light emitted from the light source;
The one linearly polarized light transmitted through the polarizing plate is reflected toward the image display surface of the reflective liquid crystal display panel, and the one linearly polarized light emitted from the image display surface of the reflective liquid crystal display panel is a polarizing beam splitter having a light transmitting and reflecting surface that transmits the other linearly polarized light whose polarization axis is orthogonal,
A first transparent member having a light refractive index higher than that of an air layer, disposed between the image display surface of the reflective liquid crystal display panel and the light transmissive and reflective surface of the polarizing beam splitter. When,
a second transparent member on which the other linearly polarized light transmitted through the light transmissive reflection surface of the polarizing beam splitter is incident;
a housing covering the second transparent member;
A reflective liquid crystal display device having
The diffuser plate is arranged on the surface of the first transparent member at a position facing a light incident surface on which the one linearly polarized light transmitted through the polarizing plate is incident,
the light exit surface of the diffusion plate is inclined with respect to the light entrance surface of the first transparent member;
the one linearly polarized main luminous flux transmitted through the polarizing plate is totally reflected by the inner surface of the first transparent member and then enters the light transmissive and reflective surface of the polarizing beam splitter;
An air layer capable of confining part of stray light is interposed between the side surface of the second transparent member located on the outer peripheral side of the light emitting surface of the second transparent member and the side surface of the housing. doing,
A reflective liquid crystal display device characterized by:
2. The method according to claim 1, wherein a light absorbing portion is formed in a region of the surface of at least one of the first transparent member and the second transparent member, excluding the optical surface. reflective liquid crystal display device.

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