JP2005121968A - Spatially light modulated panel and liquid crystal image display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spatially light modulated panel, in which the outside of an image display region on a screen is properly blackened (darkened) in a liquid crystal image display device constructed by using a liquid crystal panel. <P>SOLUTION: The spatially light modulated panel is equipped with a liquid crystal display element 15 and a light shielding plate 22 having an opening part 21 with an aspect ratio different from that of an effective pixel region in the liquid crystal display element 15, and allowing the peripheral part of the opening part 21 to shield unwanted illumination light with which the outside of the opening part 21 is irradiated. In the light shielding plate 22, a side peripheral part serves as a heat sink part 22a. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a reflective spatial light modulation panel and a liquid crystal image display device configured using the spatial light modulation panel.

  Conventionally, as an image display device, a liquid crystal image display device (liquid crystal projector) configured using a reflective liquid crystal panel which is a spatial light modulation panel has been proposed. This liquid crystal image display device condenses illumination light emitted from a light source on a liquid crystal panel via a mirror or the like to illuminate the liquid crystal panel, and modulates and reflects the modulated light that is modulated by the liquid crystal panel. Thus, an image is formed on the screen. That is, in this liquid crystal image display device, an image displayed on the liquid crystal panel is enlarged by the imaging lens and projected onto the screen, thereby displaying an image.

  In such a liquid crystal image display device, when illumination light is irradiated to a portion other than the effective pixel area of the liquid crystal panel, such unnecessary light becomes stray light, and the quality of the display image is impaired. There is a risk of generating excessive heat. Therefore, in the liquid crystal image display device, it is necessary to shield unnecessary illumination light that is irradiated to areas other than the effective pixel area of the liquid crystal panel.

  In the case of providing a light shielding plate for shielding such unnecessary illumination light, if the light shielding plate is in contact with the liquid crystal panel, the temperature of the counter electrode substrate in the liquid crystal panel rises, and birefringence occurs. Is induced, causing black screen unevenness.

  Therefore, in the conventional liquid crystal image display device, in order to solve such a problem, as described in Patent Document 1 and Patent Document 2, the liquid crystal panel and the light shielding plate are physically separated from each other. I try to install it.

Furthermore, if the liquid crystal panel and the light shielding plate are simply placed at a distance, dust enters from the gap between the liquid crystal panel and the light shielding plate and adheres to the liquid crystal panel, thereby degrading the display screen quality. Therefore, as described in Patent Document 3, a dustproof member made of a material having dustproofness and stretchability is sandwiched between the liquid crystal panel and the light shielding plate.
Japanese Patent No. 3326614 US Pat. No. 5,576,854 JP-A-11-305574

  By the way, in the liquid crystal image display device as described above, the ratio of the horizontal length to the vertical length (aspect ratio) of the display screen is 4 to 3. Therefore, many liquid crystal panels have an aspect ratio of 4 to 3.

  On the other hand, in recent years, an image signal having an aspect ratio of 16: 9 is often used. Such image signals are stored in, for example, so-called “movie software”.

  When an image signal with an aspect ratio of 16: 9 is displayed when the aspect ratio of the liquid crystal panel is 4: 3, a strip-shaped non-display portion (window) appears at the upper and lower portions of the display image. It is desirable that such a non-display portion does not reflect illumination light at all, but the reflected light from such a non-display portion is not completely zero. As a result, the non-display portion on the screen may not be sufficiently black (dark).

  In such a case, the non-display portion on the screen cannot be made sufficiently black (dark) even if the light shielding plate as described above is processed to black.

  The present invention has been proposed in view of the above-described circumstances, and when displaying an image signal having an aspect ratio different from the aspect ratio of the liquid crystal panel, the non-display portion can be made sufficiently black (dark). It is an object of the present invention to provide a spatial light modulation panel configured as described above and a liquid crystal image display device configured using such a spatial light modulation panel.

  In order to solve the above-described problem, a spatial light modulation panel according to the present invention includes a spatial light modulation element and an opening having an aspect ratio different from the aspect ratio of the effective pixel region in the spatial light modulation element. An unnecessary illumination light irradiated to the outside of the light is blocked by an edge portion of the opening, and a light shielding plate thermally insulated from the spatial light modulation element is provided.

  It is desirable that the light shielding plate has a heat sink part at the side edge part.

  In this spatial light modulation panel, unnecessary illumination light irradiated outside the opening of the light shielding plate is not blocked by the light shielding plate and reaches the spatial light modulation element. Does not cause degradation of image quality.

  Further, in this spatial light modulation panel, the spatial light modulation element and the light shielding plate are thermally insulated, and the light shielding plate has a heat sink part at the side edge portion, so that the temperature of the spatial light modulation element increases. Is suppressed and deterioration of the display image is prevented.

  The liquid crystal image display device according to the present invention includes a light source, a spatial light modulation panel, an illumination optical system that guides illumination light emitted from the light source and illuminates the spatial light modulation panel with the illumination light, and a spatial light modulation panel. An image forming optical system for forming an image, and the spatial light modulation panel includes a spatial light modulation element and an opening having an aspect ratio different from an aspect ratio of an effective pixel area in the spatial light modulation element. A light shielding plate that shields unnecessary illumination light irradiated to the outside of the portion by the edge portion of the opening and is thermally insulated from the spatial light modulation element. It has a heat sink part.

  In this liquid crystal image display device, in the spatial light modulation panel, unnecessary illumination light irradiated to the outside of the opening of the light shielding plate is not blocked by the light shielding plate, so that it does not reach the spatial light modulation element. Degradation of display image quality in the liquid crystal image display device is not caused.

  Further, in this liquid crystal image display device, in the spatial light modulation panel, the spatial light modulation element and the light shielding plate are thermally insulated, and the light shielding plate has a heat sink portion at the side edge portion. The temperature rise of the light modulation element is suppressed, and display image deterioration is prevented.

  In the spatial light modulation panel according to the present invention, unnecessary illumination light that irradiates the outside of the opening of the light shielding plate does not reach the spatial light modulation element, so that the quality of the display image in the liquid crystal image display device is degraded. (A state in which a non-display portion that occurs when an image having an aspect ratio different from the aspect ratio of the spatial light modulator is displayed is not sufficiently black (dark)).

  For example, when an image signal having an aspect ratio of 16: 9 is displayed using a spatial light modulation element having an aspect ratio of 4: 3, which is currently mainstream, It can be made sufficiently black (dark), and the contrast of the display image can be improved.

  Further, in this spatial light modulation panel, the spatial light modulation element and the light shielding plate are thermally insulated, and the light shielding plate has a heat sink part at the side edge portion, so that the temperature of the spatial light modulation element increases. The display image can be prevented from deteriorating due to the temperature rise of the spatial light modulator.

  That is, according to the present invention, in a liquid crystal image display device configured using a liquid crystal panel, a spatial light modulation panel in which deterioration of display image quality in the liquid crystal image display device is prevented, and such a spatial light modulation panel are used. The liquid crystal image display apparatus comprised can be provided.

  Hereinafter, embodiments of a liquid crystal image display device and a spatial light modulation panel according to the present invention will be described in detail with reference to the drawings.

[Embodiment of Liquid Crystal Image Display Device]
FIG. 1 is a plan view showing a configuration of an image display apparatus configured using a spatial light modulation panel according to the present invention.

  In this image display device, as shown in FIG. 1, for example, white light emitted from a lamp 1 that is a xenon arc lamp is collected by a concave mirror and incident on a color separation mirror 3 via a mirror 2. .

  Of the white light incident on the color separation mirror 3, red (R) light passes through the color separation mirror 3, and cyan light (G + B) is reflected by the color separation mirror 3 and enters the color separation mirror 4. Of the cyan light incident on the color separation mirror 4, blue (B) light is transmitted through the color separation mirror 4 and incident on the polarization prism 11. Of the cyan light incident on the color separation mirror 4, green (G) light is reflected by the color separation mirror 4 and enters the polarizing prism 10.

  On the other hand, the red (R) light transmitted through the color separation mirror 3 is incident on the polarizing prism 9 through the mirror 5.

  The B light incident on the polarizing prism 11 reflects only the S-polarized component at the joint surface and enters the liquid crystal panel 8 for B light, which is a reflective spatial light modulation panel. The S-polarized component incident on the liquid crystal panel 8 is polarized and modulated by the liquid crystal panel 8 and reflected to become a P-polarized component. The reflected light from the liquid crystal panel 8 passes through the joint surface of the polarizing prism 11 and enters the color combining prism 12.

  Further, only the S-polarized light component of the G light incident on the polarizing prism 10 is reflected by the joint surface, and is incident on the G light liquid crystal panel 7 which is a reflective spatial light modulation panel. The S-polarized component incident on the liquid crystal panel 7 is polarized and modulated by the liquid crystal panel 7 and reflected to become a P-polarized component. The reflected light from the liquid crystal panel 7 passes through the joint surface of the polarizing prism 10 and enters the color synthesis prism 12.

  Furthermore, only the S-polarized light component of the R light incident on the polarizing prism 9 is reflected by the joint surface, and is incident on the liquid crystal panel 6 for R light, which is a reflective spatial light modulation panel. The S-polarized light component incident on the liquid crystal panel 6 is polarized and modulated by the liquid crystal panel 6 and reflected to become a P-polarized light component. The reflected light from the liquid crystal panel 6 passes through the joint surface of the polarizing prism 9 and enters the color synthesis prism 12.

  Each of the liquid crystal panels 6, 7, and 8 is applied with a voltage corresponding to the display image, and modulates the incident R light, G light, and B light according to each color component of the display image.

  The R light, G light, and B light incident on the color combining prism 12 are combined in the color combining prism 12, projected onto the screen 14 by the projection lens 13 serving as an imaging lens, and imaged on the screen. . In this way, an image is displayed on the screen 14.

[Embodiment of Spatial Light Modulation Panel]
Next, the structure of the liquid crystal panels 6, 7, and 8 which are the spatial light modulation panels according to the present invention will be described.

  FIG. 2 is an exploded perspective view showing the configuration of the liquid crystal panels 6, 7, 8 which are the spatial light modulation panels according to the present invention. In the following description, the front side in FIG. 2 is described as “upper side”.

  As shown in FIG. 2, these liquid crystal panels 6, 7, and 8 are configured as a liquid crystal panel block having a dustproof structure and are incorporated in a liquid crystal image display device.

  This liquid crystal panel block includes a reflective liquid crystal display element 15 as shown in FIG. The liquid crystal display element 15 is bonded and fixed to the front surface portion of the base 16 that also serves as a heat sink. Further, a flexible substrate 17 for applying a voltage to the liquid crystal display element 15 is connected to the liquid crystal display element 15.

  The first dust-proof members 18 and 19 are fixed to the front surface portion of the base 16 to which the liquid crystal display element 15 is bonded, on both sides of the liquid crystal display element 15 by an adhesive or an adhesive. Yes. Of these first dust-proof members 18, 19, one dust-proof member 18 is for preventing intrusion of dust from between the flexible substrate 17 and the base 16. Of the first dust-proof members 18 and 19, the other dust-proof member 19 is for closing a gap generated by a step formed on the front surface portion of the base 16.

  And the 2nd dustproof member 20 is being fixed to the front side of these 1st dustproof members 18 and 19 with the adhesive or the adhesive agent. The second dustproof member 20 is formed in a frame shape so as to surround the periphery of the liquid crystal display element 15.

  On the front side of the second dustproof member 20, a light shielding plate 22 having an opening 21 formed in the center is disposed.

  FIG. 3 is a front view showing the positional relationship between the liquid crystal display element 15 and the opening 21 of the light shielding plate 22.

  The light shielding plate 22 is for preventing illumination light from being irradiated to a region wider than the opening 21 in the effective pixel region of the liquid crystal display element 15. That is, the opening 21 of the light shielding plate 22 has an aspect ratio different from the aspect ratio (aspect ratio) of the effective pixel region of the liquid crystal display element 15 as shown in FIG. For example, when the aspect ratio of the effective pixel region of the liquid crystal display element 15 is 4 to 3, the aspect ratio of the opening 21 is 16 to 9.

  Further, as shown in FIG. 2, the side edge portion of the light shielding plate 22 is a heat sink portion 22 a provided with a plurality of pieces extending from the light shielding plate 22. The light shielding plate 22 is heated by irradiation with illumination light. However, when the air is blown to the heat sink part 22a, the heat sink part 22a dissipates heat and is cooled.

  FIG. 4 is a perspective view showing the shape of the light shielding plate in the spatial light modulation panel.

  The light shielding plate 22 is fixed to the base 16, but is disposed as physically separated as possible from the base 16 in order to thermally insulate the light shielding plate 22 from the liquid crystal display element 15. The That is, the base 16 includes a spacer portion 16a for minimizing the contact area of the light shielding plate 22 with the base 16, and the spacer 16a contacts the light shielding plate 22 only at the spacer portion 16a. Alternatively, the base 16 comes into contact with the light shielding plate 22 via a separate spacer, and does not come into direct contact. In this case, the spacer is made of a material having low thermal conductivity such as glass or plastic, and thermally shields the light shielding plate 22 and the liquid crystal display element 15.

  In this spatial light modulation panel, since the liquid crystal display element 15 and the light shielding plate 22 are thermally insulated, the temperature rise of the liquid crystal display element 15 can be suppressed, and the display due to the temperature rise of the liquid crystal display element 15 can be suppressed. Image degradation can be prevented.

  And the illumination light irradiated to the area | region outside the opening part 21 of the light-shielding plate 22 is absorbed by this light-shielding plate 22, and does not reach the liquid crystal display element 15, but the quality of the display image in a liquid crystal image display device. Deterioration (a state in which the outside of the screen display area on the screen 14 is not sufficiently black (dark)) does not occur.

  As shown in FIG. 2, a frame-shaped holder 24 for holding the wave plate 23 is disposed and held on the front side of the light shielding plate 22. Frame-shaped dustproof members 25 and 26 are fixed to the front and back portions of the holder 24 by an adhesive or an adhesive, respectively. The wave plate 23 is fixed to the back surface of the holder 24 with an adhesive tape 27.

  The holder 24 can be rotated around the optical axis center of the illumination light between the guide members formed at two positions on the front surface of the light shielding plate 22, and the lever formed on the side surface of the holder 24 is operated. By doing so, the azimuth angle of the wave plate 23 can be adjusted. In this way, the polarization of illumination light can be adjusted.

  Moreover, as each dust-proof member 18, 19, 20, 25, 26, elastic members, such as foamed rubber, urethane foam, and ethylene foam, can be used. In particular, urethane foam and ethylene foam are particularly preferable materials because they have moderate elasticity and are less likely to generate dust from these materials themselves.

  A frame-shaped holding member 28 having an opening at the center is disposed on the front side of the holder 24. The holding member 28 is made of, for example, a metal material such as stainless steel (SUS304). A hood 32 made of silicone rubber is formed around the opening of the holding member 28 by so-called outsert molding.

  Screw holes 29, 30, and 31 are formed at the four corners of the base 16, the light shielding plate 22, and the holding member 28. The base 16, the light shielding plate 22, and the holding member 28 are fastened and fixed to each other by screws (not shown) inserted through the screw holes 29, 30, and 31.

  A frame-shaped focus plate 33 is disposed on the front side of the holding member 28. When the hood 32 is in close contact with the back surface of the focus plate 33, dust prevention between the focus plate 33 and the holding member 28 is achieved. Even if the distance between the focus plate 33 and the holding member 28 is wide, the hood 32 is formed by outsert molding with respect to the holding member 28, so that the distance between the focus plate 33 and the holding member 28 is increased. Good dustproof can be achieved.

  The liquid crystal panel block configured as described above is assembled in a clean bench or a clean room. And this liquid crystal panel block can maintain the dust-proof with respect to the liquid crystal display element 15 by having the above structures.

  Since the wave plate 23 is separated from the element surface of the liquid crystal display element 15, even if dust adheres to the wave plate 24, this dust image is not formed on the screen 14. The dust does not affect the image displayed on the screen 14.

  As described above, the liquid crystal panel block according to the present invention has an excellent dustproof effect and can eliminate the adverse effect on the display image caused by unnecessary light. Therefore, an image display using this liquid crystal panel block is possible. It is possible to display a high-quality image in the apparatus.

  In the above-described embodiment, the heat sink portion 22a is provided with a plurality of pieces extending on one side of the side edge portion of the light shielding plate 22, but the present invention is in this form. It is not limited. For example, a similar section may be extended in the other side of the side edge portion of the light shielding plate 22 facing the one side, and the heat sink portions 22 may be provided in the side edge portions on both sides of the light shielding plate 22. it can. Further, the heat sink portion 22a does not have to be configured by providing a section in the plane of the light shielding plate 22. For example, the heat sink part 22a having a structure in which a section is bent in an L shape with respect to the surface including the light shielding plate 22 can be configured.

  Further, although the above-described embodiment is suitable for use in a liquid crystal image display device (liquid crystal projector) using a reflective liquid crystal display element, the present invention uses a transmissive liquid crystal display element. It is also possible to apply to a conventional liquid crystal image display device.

It is a top view which shows the structure of the image display apparatus comprised using the spatial light modulation panel which concerns on this invention. It is a disassembled perspective view which shows the structure of the spatial light modulation panel which concerns on this invention. It is a front view which shows the positional relationship of the liquid crystal display element in the said spatial light modulation panel, and the opening part of a light-shielding plate. It is a perspective view which shows the shape of the light-shielding plate in the said spatial light modulation panel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light source 6, 7, 8 Liquid crystal panel 13 Imaging lens 15 Liquid crystal display element 21 Opening part 22 Light-shielding plate

Claims (3)

A spatial light modulator;
The spatial light modulator has an opening having an aspect ratio different from the aspect ratio of the effective pixel region, and unnecessary illumination light irradiated to the outside of the opening is blocked by an edge portion of the opening and the space. A spatial light modulation panel comprising: a light shielding plate thermally insulated from the light modulation element.   The spatial light modulation panel according to claim 1, wherein the light shielding plate has a heat sink portion at a side edge portion. A light source;
A spatial light modulation panel;
An illumination optical system for guiding illumination light emitted from the light source and illuminating the spatial light modulation panel with the illumination light;
An imaging optical system for forming an image of the spatial light modulation panel;
The spatial light modulation panel has a spatial light modulation element and an opening having an aspect ratio different from the aspect ratio of the effective pixel area in the spatial light modulation element, and unnecessary illumination light irradiated outside the opening. And a light-shielding plate that is thermally insulated from the spatial light modulator and is blocked by an edge portion of the opening,
The light-shielding plate has a heat sink portion at a side edge portion. A liquid crystal image display device, wherein:

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