JP2005156675A - Optical modulation device, optical device and projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical modulation device excellent in heat radiation performance and cooling performance. <P>SOLUTION: The optical modulation device 440R equipped with an optical modulation element 441R which modulates a light flux to be incident according to image information and forms an optical image has an incident side holding frame 82R on which an opening to be formed at a position according to an image formation area of the optical modulation element 441R is formed and holds the optical modulation element 441R from the light flux incident side, an emission side holding frame 81R which has an opening 81R1 to be formed at a position according to the opening 82R1 of the incident side holding frame 82R, is combined with the incident side holding frame 82R and holds the optical modulation element 441R from the light flux emission side and a linking frame 83R which links one end part of the incident side holding frame 82R and the emission side holding frame 81R to the other end part of the incident side holding frame 82R and the emission side holding frame 81R opposite to the end part to be mutually heat conductive and guides a cooling wind which cools the optical modulation element 441R between the end parts. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a light modulation device including a light modulation element that modulates an incident light beam according to image information to form an optical image, an optical device including the light modulation device, and a projector including the optical device.

Conventionally, projectors have been used for presentations in meetings and the like, and in recent years, they have also been used for home theaters.
In such a projector, a light beam emitted from a light source is modulated according to image information by a light modulation device using a liquid crystal panel or the like, and is enlarged and projected onto a screen or the like.

In addition, the projector includes a light modulation element incorporated in the light modulation device and an optical element such as a polarizing plate provided at the front stage and the rear stage of the light modulation apparatus, and simplifies the mounting structure to improve assembly. At the same time, the projector is also downsized.
For example, a light modulation device is known in which a light modulation element is housed in a container-shaped incident-side holding frame having a recess and pressed and fixed by a plate-shaped emission-side holding frame. In this light modulation device, the light modulation device and the color synthesizing optical device are integrated by inserting pin-shaped members into holes formed at the four corners of the incident side holding frame, so that the structure is simplified and assembled. This improves the performance (see Patent Document 1).

By the way, in such a projector, miniaturization is promoted as described above, and a bright projected image is also promoted by increasing the luminance of the light source.
As miniaturization and higher brightness are promoted, it has become an important issue how to effectively cool light modulation elements such as liquid crystal panels, which have been incorporated into the light modulation elements from the outside. A cooling method in which cooling air is blown is employed.
However, with the method of blowing cooling air, especially in home theater applications, the motor noise of the cooling fan may become a problem, and while the internal heat density increases with downsizing and higher brightness, the cooling efficiency is also improved. There is a limit.
Therefore, a liquid crystal panel is affixed to the plate-shaped incident side holding frame, and this incident side holding frame is connected to the plate-shaped emission side holding frame opposed and spaced apart by a thermally conductive pin-shaped member, and color synthesis is performed. It has been proposed that a metal pedestal is disposed on an end surface orthogonal to a plurality of light incident end surfaces of the optical device, and that the overheated light modulation device is effectively cooled by a conductive heat dissipation mechanism via the pin-shaped member and the pedestal. (See Patent Document 2).

Japanese Patent Laid-Open No. 10-10994 (FIGS. 5 and 6) JP 2002-244214 A (paragraphs [0026] [0027], FIG. 5)

  However, in the method described in Patent Document 2, the liquid crystal panel is in contact only with the incident side holding frame, and the incident side holding frame and the emission side holding frame can partially conduct heat through the pin-shaped member. Therefore, the conduction heat radiation is mainly performed only from the side in contact with the incident side holding frame, and the conduction heat radiation amount from the emission side holding frame is small. Therefore, a temperature difference is likely to occur between the incident side and the emission side of the liquid crystal panel, and it cannot be said that the light modulation device can be effectively cooled.

  In view of the above problems, an object of the present invention is to provide a light modulation device excellent in heat dissipation performance and cooling performance, an optical device including the light modulation device, and a projector including the optical device.

The light modulation device of the present invention is a light modulation device including a light modulation element that modulates an incident light beam according to image information to form an optical image, and the position of the light modulation element according to an image formation region An incident side holding frame that holds the light modulation element from the light beam incident side;
An exit-side holding frame that has an opening formed at a position corresponding to the opening of the incident-side holding frame, is combined with the incident-side holding frame, and holds the light modulation element from the light beam exit side, and the incident One end portion of the side holding frame and the exit side holding frame, and the other end portion of the incident side holding frame and the exit side holding frame facing the end portion are connected to each other so as to be able to conduct heat, and these end portions And a connecting frame for guiding cooling air for cooling the light modulation element.

Here, the emission side holding frame is a frame-like member interposed between the light modulation device and the color synthesis optical device, and the emission side holding frame may be directly fixed to the color synthesis optical device. It can also be indirectly fixed via a frame-like member, a plate-like member or the like.
The shape, material, and fixing mode of the exit side holding frame, incident side holding frame, connecting frame, and the like can be appropriately selected in consideration of strength, cost, heat dissipation, and the like.

According to the present invention, the heat generated from the light modulation element passes from the one end of the incident side holding frame and the emission side holding frame to the other end via the frame of the connection frame, and the incident side holding frame and the emission side. Conventionally, heat conduction between the incident-side holding frame and the emission-side holding frame is only partially achieved by the pin-like member, and the light-modulating element on the emission-side holding frame side. Compared with having no effective heat radiation path, the conductive heat radiation performance can be improved reliably.
Further, the connecting frame serves as a side wall between the end portions of the incident side holding frame and the emission side holding frame, and the light modulation element located between the incident side holding frame and the emission side holding frame is cooled by the cooling air on both the incident side and the emission side. Thus, the temperature of the light modulation element is not uneven, and the cooling performance can be significantly improved without enhancing the fan air blowing due to the synergistic effect with the improvement of the heat dissipation performance.
Here, in the present invention, for example, it is preferable to connect the incident side holding frame and the emission side holding frame via the inner peripheral surface in a tunnel shape. In this configuration, the connecting frame has a larger heat capacity than the incident side holding frame and the emission side holding frame, and the conduction heat radiation performance is further improved.

In the light modulation device according to the aspect of the invention, it is preferable that the connection frame is formed of a heat conductive material.
Here, Mg alloy, Al alloy, Mo-Cu alloy, Ti alloy, Fe-Ni alloy, etc. are employable as a heat conductive material. All of these materials have a thermal conductivity of 10 W / (m · K) or more.
According to the present invention, the heat conduction between the incident side holding frame and the emission side holding frame is more efficiently performed by the thermal conductivity of the connecting frame, so that the conduction heat radiation performance can be further improved.

In the light modulation device according to the aspect of the invention, it is preferable that the connection frame is provided with a rectifying member extending along the flow of the cooling air at a position corresponding to each of the end portions to be connected.
According to the present invention, since the flow of the cooling air is rectified by the rectifying member, the cooling air is blown out between the end portions of the incident side holding frame and the emission side holding frame, thereby further improving the cooling performance. it can. Even when the cooling air is swirled due to the influence of the rotation of the fan or the like, a sufficient amount of cooling air is supplied to the light modulation device, and uneven temperature of the light modulation element can be prevented.
In addition, when a polarizing plate or the like is interposed between the light modulation device and the color synthesis optical device, a gap generated between the connection frame and the color synthesis optical device can be closed by the rectifying member. Thereby, it is possible to prevent the cooling air and the light flux from leaking from the gap.
Here, the position where the rectifying member is provided may be on either the light beam incident side or the light beam emission side of the connecting frame. Furthermore, by providing a rectifying member on both the light beam incident side and the light beam emission side, the cooling air can be rectified on both the light beam incident side and the light beam emission side, and the light modulation element can be efficiently cooled from both sides.

In the light modulation device according to the aspect of the invention, it is preferable that the rectifying members are bent so as to approach each other toward the upstream side of the cooling air.
Here, it is preferable that the edge part of the baffle member is extended toward the cooling-air blowing outlet. It is more preferable if the end of the flow regulating member reaches the outlet.
According to the present invention, the cooling air blown out from the outlet with a strong wind pressure is immediately blown into the connecting frame from the end of the rectifying member without leakage, so that pressure loss and air volume loss in the vicinity of the outlet can be avoided, and the light modulation device The cooling performance can be improved with certainty.

In the light modulation device according to the aspect of the invention, the connection frame may connect the portion connecting the one end portion and the portion connecting the other end portion so as to conduct heat at a position on the downstream side of the cooling air. It is preferable to provide a connecting portion.
According to the present invention, the cooling air blown into the inside of the connecting frame hits the connecting portion and wraps between the incident side holding frame and the emission side holding frame, so that the light modulation device can be cooled more effectively.

In the light modulation device according to the aspect of the invention, it is preferable that a heat conductive elastic material is interposed between the incident side holding frame, the emission side holding frame, and the connection frame.
Here, as the heat conductive elastic material, a heat conductive silicon adhesive, heat conductive grease, or the like can be employed.
According to the present invention, the incident side holding frame, the emission side holding frame, and the connection frame are brought into close contact with each other due to the presence of the heat conductive elastic material. Can be made.

An optical device of the present invention includes a light modulation device including a light modulation element that modulates an incident light beam according to image information to form an optical image, and a light beam incident end face that faces the light modulation device, An optical device including a color synthesis optical device that synthesizes an optical image formed by the light modulation device, wherein the light modulation device is the light modulation device described above.
According to the present invention, since the light modulation device has the operations and effects as described above, it is possible to provide an optical device that can enjoy the same operations and effects and is excellent in heat dissipation performance and cooling performance.

A projector according to the present invention is a projector that modulates a light beam emitted from a light source in accordance with image information to form an optical image and projects an enlarged image, and includes the above-described optical device.
According to the present invention, since the optical device has the functions and effects as described above, the same functions and effects can be enjoyed. Therefore, it is possible to prevent an internal temperature rise due to downsizing and high brightness, and to achieve performance as expected and improve reliability.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
(1) External Configuration FIG. 1 is a perspective view of a projector 1 according to the present embodiment as viewed from the upper front side. FIG. 2 is a perspective view of the projector 1 as viewed from the lower front side. FIG. 3 is a perspective view of the projector 1 as seen from the rear rear side.
The projector 1 modulates the light beam emitted from the light source according to the image information, and enlarges and projects it on a projection surface such as a screen. As shown in FIGS. 1 to 3, the projector 1 includes an exterior case 2 as a substantially rectangular parallelepiped casing, and a projection lens 3 exposed from the exterior case 2.
The projection lens 3 enlarges and projects an optical image modulated according to image information by the main body of the projector 1. The projection lens 3 is configured as a combined lens in which a plurality of lenses are housed in a cylindrical lens barrel, and includes a lever 3A (FIG. 1) that changes the relative positions of the plurality of lenses. And the magnification is adjustable.

The outer case 2 is a casing made of synthetic resin and houses the main body portion of the projector 1. As shown in FIGS. 1 to 3, the exterior case 2 includes an upper case 11 that covers the upper part of the projector 1, a lower case 12 that covers the lower part of the projector 1, and a rear case 13 that covers the rear part of the projector 1. (FIG. 3). The upper case 11, the lower case 12, and the rear case 13 are fixed with screws or the like, and are configured to be detachable as appropriate.
As shown in FIG. 1 and FIG. 3, the upper case 11 includes an upper surface portion 11A, a front surface portion 11B, and side surface portions 11C (FIG. 1) and 11D (FIG. 2) that constitute the upper surface, front surface, and side surface of the projector 1, respectively. 3).

As shown in FIG. 1, an exhaust port 17 is formed on the left side of the front portion 11 </ b> B when viewed from the front, and air exhausted from a cooling fan disposed inside is exhausted through the exhaust port 17. Is done.
Further, as shown in FIG. 1, a substantially circular notch 18 is formed on the right side of the front surface portion 11B as shown in FIG. The notch 18 exposes the tip portion of the projection lens 3.

  As shown in FIGS. 1 to 3, the lower case 12 includes a bottom surface portion 12A (FIG. 2), side surface portions 12B (FIG. 1), and 12C (FIG. 1) that constitute a part of the bottom surface, side surface, and back surface of the projector 1, respectively. 2, FIG. 3), and a back surface portion 12 </ b> D (FIG. 3).

In the bottom surface portion 12A, a rectangular opening 21 is formed at a substantially central portion on the left side when viewed from below. A lamp cover 22 that covers the opening 21 is detachably provided in the opening 21.
Further, in this bottom surface portion 12A, the corner on the right side as viewed from below has a stepped shape recessed inward. An air inlet 23 for sucking cooling air from the outside is formed at the corner. The intake port 23 is detachably provided with an intake port cover 23A that covers the intake port 23. The intake port cover 23A has a plurality of openings 23B. An air filter (not shown) is provided inside these openings 23B to prevent dust from entering the inside.

(2) Internal Configuration FIG. 4 is a diagram showing the internal structure of the projector 1 with the upper case 11 and the internal control board etc. of the projector 1 removed.
The exterior case 2 accommodates a main body portion of the projector 1, and this main body portion extends in the left-right direction at a substantially central portion in the projection direction, and has a substantially L-shape in plan view extending one end forward. The optical unit 4, a control board (not shown) disposed above the optical unit 4 on the projection lens 3 side, power is supplied to the control board and the light source device 411, and the back part and one side part are provided. A power supply unit 6 that is arranged in a substantially L shape in plan view and supplies power to the light source device 411 and the control board (not shown), the position corresponding to the intake port 23 and the exhaust port 17, and the position of the power supply unit 6 And a cooling unit 7 including three cooling fans arranged at the corner portions.

(2-1) Structure of Optical Unit 4 FIG. 5 is a diagram schematically showing an optical system of the optical unit 4.
The optical unit 4 modulates the light beam emitted from the light source device according to image information to form an optical image, and forms a projected image on the screen via the projection lens 3. As shown in FIG. 4 or 5, the optical unit 4 includes an integrator illumination optical system 41, a color separation optical system 42, a relay optical system 43, an optical modulation device, and a color synthesis optical device. 44 and an optical component housing 45 (FIG. 4) in which these optical components 41, 42, 43, 44 are housed and arranged are functionally divided.
The integrator illumination optical system 41 is an optical system for making the luminous flux emitted from the light source uniform in the illumination optical axis orthogonal plane. As shown in FIG. 5, the integrator illumination optical system 41 includes a light source device 411, a first lens array 412, a second lens array 413, a polarization conversion element 414, and a superimposing lens 415.

  The light source device 411 includes a light source lamp 416 as a radiation light source, a reflector 417, and an explosion-proof glass 418 that covers a light exit surface of the reflector 417. Then, the radial light beam emitted from the light source lamp 416 is reflected by the reflector 417 to be a substantially parallel light beam, and is emitted to the outside. In the present embodiment, a high-pressure mercury lamp is used as the light source lamp 416, and a parabolic mirror is used as the reflector 417. The light source lamp 416 is not limited to a high-pressure mercury lamp, and may be a metal halide lamp, a halogen lamp, or the like. Moreover, although the parabolic mirror is employ | adopted as the reflector 417, you may employ | adopt the structure which has arrange | positioned the collimating concave lens to the output surface of the reflector which consists of not only this but an ellipsoidal mirror.

The first lens array 412 has a configuration in which small lenses having a substantially rectangular outline when viewed from the illumination optical axis direction are arranged in a matrix. Each small lens splits the light beam emitted from the light source lamp 416 into partial light beams and emits them in the direction of the illumination optical axis.
The second lens array 413 has substantially the same configuration as the first lens array 412, and includes a configuration in which small lenses are arranged in a matrix. The second lens array 413 has a function of forming an image of each small lens of the first lens array 412 on liquid crystal panels 441R, 441G, and 441B described later of the optical device 44 together with the superimposing lens 415.

The polarization conversion element 414 converts the light from the second lens array 413 into approximately one type of polarized light, thereby improving the light use efficiency in the optical device 44.
Specifically, each partial light beam converted into approximately one kind of polarized light by the polarization conversion element 414 is finally substantially superimposed on liquid crystal panels 441R, 441G, 441B, which will be described later, of the optical device 44 by the superimposing lens 415. . In a projector using liquid crystal panels 441R, 441G, and 441B of a type that modulates polarized light, only one type of polarized light can be used, and therefore approximately half of the light flux from the light source lamp 416 that emits randomly polarized light is not used. For this reason, by using the polarization conversion element 414, the light beam emitted from the light source lamp 416 is converted into substantially one type of polarized light, and the light use efficiency in the optical device 44 is enhanced. Such a polarization conversion element 414 is introduced in, for example, Japanese Patent Application Laid-Open No. 8-304739.

The color separation optical system 42 includes two dichroic mirrors 421 and 422 and a reflection mirror 423. The plurality of partial light beams emitted from the integrator illumination optical system 41 are separated into three color lights of red (R), green (G), and blue (B) by two dichroic mirrors 421.
The relay optical system 43 includes an incident side lens 431, a relay lens 433, a UV cut filter 434, and reflection mirrors 432 and 435. The relay optical system 43 has a function of guiding blue light, which is color light separated by the color separation optical system 42, to a liquid crystal panel 441B described later of the optical device 44.

  At this time, in the dichroic mirror 421 of the color separation optical system 42, among the light beams emitted from the integrator illumination optical system 41, the green light component and the blue light component are transmitted, and the red light component is reflected. The red light reflected by the dichroic mirror 421 is reflected by the reflection mirror 423, passes through the field lens 424, and reaches the red liquid crystal panel 441R. The field lens 424 converts each partial light beam emitted from the second lens array 413 into a light beam parallel to the central axis (principal ray). The same applies to the field lens 424 provided on the light incident side of the other liquid crystal panels 441G and 441B.

Of the blue light and green light transmitted through the dichroic mirror 421, the green light is reflected by the dichroic mirror 422, passes through the field lens 424, and reaches the liquid crystal panel 441G for green light. On the other hand, the blue light passes through the dichroic mirror 422, passes through the relay optical system 43, passes through the field lens 424, and reaches the liquid crystal panel 441B for blue light.
The reason why the relay optical system 43 is used for blue light is that the optical path length of the blue light is longer than the optical path lengths of the other color lights, thereby preventing a reduction in light use efficiency due to light divergence or the like. Because. That is, this is to transmit the partial light beam incident on the incident side lens 431 to the field lens 424 as it is. The relay optical system 43 is configured to pass blue light of the three color lights, but is not limited thereto, and may be configured to pass red light, for example.

  The optical device 44 modulates an incident light beam according to image information to form a color image. The optical device 44 includes three incident-side polarizing plates 442 to which the respective color lights separated by the color separation optical system 42 are incident, and three viewing angle correction plates 443 disposed at the subsequent stage of the incident-side polarizing plates 442, , Three light modulation devices 440R, 440G, and 440B arranged at the subsequent stage of each viewing angle correction plate 443, and a cross dichroic prism 445 as a color synthesis optical device.

The light modulation devices 440R, 440G, and 440B include liquid crystal panels 441R, 441G, and 441B as light modulation elements, and an exit-side polarizing plate 444. The liquid crystal panels 441R, 441G, and 441B modulate and emit the light beam incident through the incident side polarizing plate 442 and the viewing angle correction plate 443 according to image information.
The liquid crystal panels 441R, 441G, and 441B are formed of a drive substrate made of sapphire glass or the like (for example, a plurality of line-shaped electrodes, electrodes constituting pixels, and TFT elements electrically connected therebetween. The liquid crystal is sealed between the substrates 441R1, 441G1, 441B1 (light beam emission side) and a counter substrate (for example, a substrate on which a common electrode is formed) 441R2, 441G2, 441B2 (light beam incident side), which is also made of sapphire glass. The control cables 441R4, 441G4, and 441B4 extend between the glass substrates (FIGS. 8 and 9). Further, a dust-proof glass 441R3 is disposed opposite to the outer side of the drive substrate 441R1, and an emission-side polarizing plate 444 is disposed opposite to the outer side of the counter substrate 441R2.

The incident side polarizing plate 442 transmits only polarized light in a certain direction out of each color light separated by the color separation optical system 42 and absorbs other light beams. A polarizing film is attached to a substrate such as sapphire glass. It has been done.
The exit side polarizing plate 444 is configured in substantially the same manner as the incident side polarizing plate 442, and transmits only polarized light in a predetermined direction among the light beams emitted from the liquid crystal panels 441R, 441G, and 441B, and absorbs other light beams. The polarization axis of the polarized light to be transmitted is set so as to be orthogonal to the polarization axis of the polarized light to be transmitted by the incident side polarizing plate 442.

The viewing angle correction plate 443 is obtained by forming an optical conversion film having a function of correcting the viewing angle of the optical image formed by the liquid crystal panels 441R, 441G, 441B on the substrate. The viewing angle correction plate 443 compensates for the birefringence that occurs in the liquid crystal panels 441R, 441G, and 441B. The viewing angle correction plate 443 enlarges the viewing angle of the projected image and improves the contrast of the projected image.
The cross dichroic prism 445 forms a color image by synthesizing optical images emitted from the emission-side polarizing plate 444 and modulated for each color light. The cross dichroic prism 445 is provided with a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light in a substantially X shape along the interface of four right-angle prisms. Three color lights are synthesized by the body multilayer film.
The light modulation devices 440R, 440G, and 440B, the exit-side polarizing plate 444, and the cross dichroic prism 445 described above are integrally unitized.

As shown in FIG. 4, the optical component casing 45 is a synthetic resin product by injection molding or the like, and includes a component storage member 451 in which the above-described optical components 41, 42, 43, and 44 are stored, and the component storage member. And a lid-like member 452 that closes the opening portion of the upper surface of 451.
The component storage member 451 includes a light source storage unit 451A in which the light source device 411 is stored, a component storage unit 451B formed in a container shape in which other optical components other than the light source device 411 are stored, and the component storage unit 451B. A projection lens installation section 451C formed on the outer side surface on which the projection lens 3 is installed.

The light source storage portion 451A is formed in a substantially box shape having an opening 451A1 (FIG. 14) on the lower end surface and an opening (not shown) on the component storage portion 451B side. The light source storage unit 451 </ b> A stores the light source device 411 via the lamp cover 22 (FIG. 2) provided on the bottom surface 12 </ b> A of the lower case 12. In addition, a slit-like opening (not shown) is formed on the front end face of the light source storage portion 451A. Similarly, a slit-like opening 451A2 (FIG. 4) is formed on the rear side end face of the light source storage 451A. And air can distribute | circulate inside and outside the light source storage part 451A through these opening parts.
Although not shown in the drawings, a plurality of grooves for fitting the optical components 412 to 415, 421 to 424, 431 to 435 slidably from above are formed in the component storage portion 451B. Further, as shown in FIG. 4, the optical device 44 is installed inside the projection lens installation unit 451C in the component storage unit 451B. Further, in the component storage unit 451B, an opening 451B1 that transmits the light beam emitted from the light source device 411 is formed on the side surface on the rear stage side of the optical device 44 as shown in FIG. Furthermore, in the component storage unit 451B, an opening 451B2 is formed on the bottom surface portion at a position corresponding to the three liquid crystal panels 441R, 441G, 441B of the optical device 44 as shown in FIG. An opening 451B3 is formed at a position corresponding to the polarization conversion element 414.

The projection lens installation unit 451C is located at the periphery of the opening 451B1 of the component storage unit 451B, and installs the projection lens 3 at a predetermined position with respect to the illumination optical axis set in the optical component housing 45. Then, an optical image emitted from the light source device 411 and formed by the optical device 44 is enlarged and projected by the projection lens 3 through the opening 451B1 of the component storage unit 451B.
As shown in FIG. 4, the lid-like member 452 closes the upper end opening portion of the component storage member 451 except for the upper portion of the optical device 44 in the component storage portion 451B. A plurality of openings (for example, an opening 452A) are formed in the lid-like member 452 so as to penetrate the front and back, and the attitude of the optical component stored in the component storage member 451 is adjusted through the opening. Is done.

(2-2) Structure of the power supply unit 6 The power supply unit 6 supplies power to the light source device 411, a control board (not shown), and the like. As shown in FIG. 4, the power supply unit 6 includes a power supply block 61 disposed along the back surface of the exterior case 2 and a light source drive block 62 disposed along one side surface of the exterior case 2. It is formed in an L shape in plan view so as to surround the light source storage portion 451A of the optical component housing 45.
The power supply block 61 supplies electric power supplied from the outside through a power supply cable connected to the connector to the light source drive block 62 and a control board (not shown).

(3) Configuration of Optical Device 44 The detailed configuration of the optical device 44 will be described with reference to FIGS.
6 shows the optical device 44 seen from above, and FIG. 7 shows the optical device 44 seen from below.
Of the optical components constituting the optical device 44, the light modulators 440R, 440G, and 440B, the exit-side polarizing plate 444, and the cross dichroic prism 445 are integrated. That is, as shown in FIGS. 6 and 7, three light modulators 440R, 440G, and 440B have openings corresponding to the image forming areas of the liquid crystal panels 441R, 441G, and 441B on different end faces of the cross dichroic prism 445. It is fixed at four corners by pin-shaped members 447R, 447G, and 447B via rectangular fixing plates 446R, 446G, and 446B.
Here, in the light modulation devices 440R, 440G, and 440B, the liquid crystal panels 441R, 441G, and 441B are held by frame members from both the incident side and the emission side of the light flux. As a result, the light modulation devices 440R, 440G, and 440B are excellent in assemblability when fixed to the cross dichroic prism 445 or when the optical device 44 is incorporated into the projector 1.

  On the other hand, in the cross dichroic prism 445, a metal pedestal 448 is installed on an end surface orthogonal to the light velocity incident end surface to which the respective light modulation devices 440R, 440G, and 440B are fixed. The pedestal 448 is fixed to the component storage member 451 so that heat of the light modulation devices 440R, 440G, 440B and the cross dichroic prism 445 is radiated through the component storage member 451 and the lower case 12 through the pedestal 448. Yes.

The light modulation device 440R includes an incident-side holding frame 82R, an emission-side holding frame 81R, and a connection frame 83R that connects the incident-side holding frame 82R and the emission-side holding frame 81R in a heat conductive manner. The liquid crystal panel 441R is held by combining the emission side holding frame 81R, the incident side holding frame 82R, and the connecting frame 83R in a nested manner.
Here, the incident side holding frame 82R, the emission side holding frame 81R, and the connection frame 83R are formed of a heat conductive material such as an Mg alloy, an Al alloy, a Mo—Cu alloy, a Ti alloy, and an Fe—Ni alloy. Yes. Note that the thermal conductivity of these materials is all 10 W / (m · K) or more, and the heat generated from the liquid crystal panels 441R, 441G, 441R is effectively dissipated due to the high thermal conductivity. Can do.
In addition, the light modulation device 440R is cooled by cooling air blown from the opening 451B2 (FIG. 15) of the component storage unit 451B.

8 and 9 show a state in which the liquid crystal panel 441R is held by the exit-side holding frame 81R. FIG. 8 is a view seen from the light beam entrance side, and FIG. 9 is a view seen from the light exit side. is there.
10 and 11 show a state in which the liquid crystal panel 441R is held by the exit-side holding frame 81R and the incident-side holding frame 82R. FIG. 10 is a view seen from the light beam incident side, and FIG. It is the figure seen from the light beam emission side.
Further, FIGS. 12 and 13 show a state in which the incident side holding frame 82R and the emission side holding frame 81R are connected by the connecting frame 83R. FIG. 12 is a view as seen from the light incident side. 13 is a view seen from the light beam exit side.
On the other hand, each of the light modulation devices 440G and 440B also includes incident-side holding frames 82G and 82B, emission-side holding frames 81G and 81B, and connection frames 83G and 83B. The description will focus on the panel 441R, and the description and illustration of the liquid crystal panels 441G and 441B having substantially the same configuration as the liquid crystal panel 441R will be omitted as appropriate.

As shown in FIGS. 8 and 9, the emission-side holding frame 81R is a substantially rectangular plate-like frame-like member that holds the liquid crystal panel 441R from the light beam emission side. Are integrally formed by press molding. An opening 81R1 corresponding to the rectangular image forming area of the liquid crystal panel 441R is formed in the approximate center of the emission side holding frame 81R, and five ring-shaped holes 81R4 are provided on the periphery. Yes. The hole 81R4 has a thick ring peripheral portion so that the pin-like members 447R, 447G, and 447B inserted into the hole 81R4 can be securely held.
In the emission side holding frame 81R, a pair of side portions 81R2 are erected from the both edges of the opening 81R1, and a control cable for the liquid crystal panel 441R is interposed between the side portions 81R2. A support portion 81R3 extends on the side opposite to the side from which 441R4 extends, and the liquid crystal panel 441R is sandwiched between the pair of side portions 81R2 and supported by the support portion 81R3.
In addition, two ribs 81R5 extend on the outer surface of the side portion 81R2 along the thickness direction of the liquid crystal panel 441R to be held.

The incident-side holding frame 82R is a container-like frame-like member having a substantially rectangular shape in plan view that holds the liquid crystal panel 441R held by the emission-side holding frame 81R from the light beam incident side, and is also shown in FIGS. Further, it is shaped so as not to overlap with the position of the hole 81R4 of the injection side holding frame 81R, and is stamped by the same heat conductive material as that of the injection side holding frame 81R.
An opening 82R1 corresponding to the rectangular image forming area of the liquid crystal panel 441R is formed in the approximate center of the incident side holding frame 82R. On the side where the control cable 441R4 of the liquid crystal panel 441R extends, A fin 82R4 in which a plurality of grooves having a heat dissipation effect are formed is provided.
In the incident-side holding frame 82R, a pair of side portions 82R2 are erected from the end edges on both short sides of the opening 82R1, and a support portion 82R3 extends between the side portions 81R2. The liquid crystal panel 441R is sandwiched between the pair of side portions 82R2 together with the emission side holding frame 81R and supported by the support portion 82R3.
Further, a concave portion 82R5 is formed on the outer surface of the side portion 82R2, and a projection 82R6 is formed in the concave portion 82R5.

As shown in FIGS. 12 and 13, the connecting frame 83R extends between a pair of side portions 83R2 facing each other and the ends of the side portions 83R2, and around the fins 82R4 of the incident side holding frame 82R. And a connection portion 83R3 that bulges out along the channel, and is formed in a substantially C-shaped channel shape, and an opening 83R1 is formed on the opposite side of the connection portion 83R3. Here, the cooling air blown into the inside of the connecting frame 83R from the opening 451B2 hits the connecting portion 83R3 and wraps around between the incident side holding frame 82R and the emission side holding frame 81R, so that the cooling efficiency is improved.
The connecting frame 83R accommodates the exit-side holding frame 81R and the incident-side holding frame 82R inside, and connects the exit-side holding frame 81R and the incident-side holding frame 82R to each other through the inner peripheral surface in a heat conductive manner. The control cable 441R4 of the liquid crystal panel 441R held by the connection frame 83R via the emission side holding frame 81R and the incident side holding frame 82R is connected to the connection frame 83R by a slit 83R4 formed in the connection portion 83R3. Extend through. Although not shown, a recess is formed inside the side portion 83R2, and this recess is engaged with the protrusion 82R6 of the incident side holding frame 82R.

Each side portion 83R2 is formed with a holding plate 83R5 that overlaps with the peripheral portion of the liquid crystal panel 441R. Moreover, the edge of each side part 83R2 protrudes in the out-of-plane direction of the surface including the side part 83R2 and the connection part 83R3, and a rectifying part 83R6 as a rectifying member is formed here. By such a rectifying unit 83R6, the cooling air blown up from the opening 451B2 is rectified and blown out between the end portions of the incident side holding frame 82R and the emission side holding frame 81R, and the cooling performance is further improved. In addition, since the rectifying unit 83R6 extends between the coupling frame 83R and the cross dichroic prism 445, the portion of the exit-side polarizing plate 444 disposed opposite to the counter substrate 441R2 of the liquid crystal panels 441R, 441G, 441B. It is possible to prevent the cooling air and light flux from leaking out.
Here, the rectifying unit 83R6 is bent so that the end portions on the opening 83R1 side are close to each other to form a bent unit 83R7. The bent portion 83R7 is connected to an opening 451B2 from which cooling air is blown out. Therefore, since the cooling air blown out from the opening 451B2 with a strong wind pressure is immediately blown into the connection frame 83R from the end of the bent portion 83R7 without leakage, pressure loss and airflow loss near the opening 451B2 can be avoided, and the light modulation device The cooling performance of 440R can be improved reliably.

The light modulation devices 440R, 440G, and 440B are assembled as follows with respect to the emission-side holding frame 81R, the incident-side holding frame 82R, and the connection frame 83R described above. Here, by assembling while filling a heat conductive silicon adhesive or heat conductive grease between the emission side holding frame 81R, the incident side holding frame 82R, and the connecting frame 83R, the incident side The holding frame 82R, the exit-side holding frame 81R, and the connecting frame 83R are in close contact with each other, so that conductive heat dissipation is improved.
First, the liquid crystal panel 441R is fitted inside the side portion 81R2 and the support portion 81R3 of the emission side holding frame 81R. Next, the exit-side holding frame 81R is placed inside the incident-side holding frame 82R so that the side portion 81R2 and the side portion 82R2 face each other. At this time, the side portion 82R2 and the side portion 81R2 are engaged with each other at the rib 81R5 portion of the emission side holding frame 81R, whereby the emission side holding frame 81R and the incident side holding frame 82R are fixed.
Then, the exit-side holding frame 81R and the incident-side holding frame 82R are accommodated from the opening 83R1. A recess (not shown) formed in the side portion 83R2 is engaged with the projection 82R6 of the incident side holding frame 82R, and the holding plate 83R5 holds the emission side holding frame 81R. Thereby, the incident side holding frame 82R and the emission side holding frame 81R that hold the liquid crystal panel 441R are held by the connection frame 83R, and the assembly of the light modulation devices 440R, 440G, and 440B is completed.

In the light modulation devices 440R, 440B, and 440G assembled in this way, heat generated from the liquid crystal panels 401R, 401G, and 401B is incident on the incident-side holding frames 82R, 82G, and 82B via the frames of the connection frames 83R, 83G, and 83B. And conduction between the end portions of the exit-side holding frames 81R, 81G, 81B, that is, the entire entrance-side holding frames 82R, 82G, 82B and the exit-side holding frames 81R, 81G, 81B. Can be made.
Further, the connecting frames 83R, 83G, and 83B serve as side walls between the end portions of the incident side holding frames 82R, 82G, and 82B and the emission side holding frames 81R, 81G, and 81B, and the liquid crystal panels 401R, 401G, and 401B are disposed on the incident side. Since the exit side is sufficiently exposed to the cooling air, the temperature of the liquid crystal panels 401R, 401G, and 401B does not vary and the cooling performance can be significantly improved.

(4) Cooling Structure FIGS. 4, 14, and 15 are diagrams illustrating the structure of the cooling unit 7. FIG. 4 shows the projector 1 with the upper case 11 and the control board removed, and FIG. 14 and FIG. 15 show it from below.
The cooling unit 7 includes an intake mechanism 70 that takes in air from the outside of the projector 1 and an exhaust mechanism 90 that discharges air warmed inside the projector 1 to the outside, and cools the inside of the projector 1.

The intake mechanism 70 circulates cooling air to the power supply unit 6, a sirocco fan 71 that introduces external cooling air into the projector 1, an intake side duct 72 that guides the cooling air discharged from the sirocco fan 71 to a predetermined position, and The sirocco fan 73 is used as a centrifugal force fan.
The sirocco fan 71 is disposed at a position corresponding to the intake port 23 (FIG. 2) formed in the bottom surface portion 12A of the exterior case 2, and the intake port 711 for sucking cooling air faces the intake port 23 so that the intake cooling A discharge port 712 that discharges air faces the lower side of the optical unit 4.
As shown in FIG. 14, the intake side duct 72 is disposed below the optical unit 4 and is connected to the discharge port 712 of the sirocco fan 71. The intake-side duct 72 has four outlets (not shown) that lead out the cooling air, and these outlets are connected to the openings 451B2 and 451B3 (FIG. 15) formed on the bottom surface of the component storage member 451. To do.
As shown in FIGS. 4 and 14, the sirocco fan 73 is disposed between the power supply block 61 and the light source drive block 62 of the power supply unit 6, that is, at the corner portion of the L-shape of the power supply unit 6. A suction port (not shown) that sucks in opposes the power supply block 61, and a discharge port (not shown) that discharges the sucked cooling air faces the light source drive block 62.

As shown in FIG. 4, the exhaust mechanism 90 is disposed so as to extend from the front end surface of the light source storage portion 451A of the optical component housing 45 to the front surface of the exterior case 2, and includes an internal duct 91, an axial fan 92, and The exhaust side duct 93 is provided.
The internal duct 91 is opposed to a slit-like opening (not shown) formed on the front end surface of the light source storage unit 451A on the base end side, and connected to the axial fan 92 on the front end side, and is stored in the light source storage unit 451A. It is a duct for receiving high-temperature air in the vicinity of the light source device 411 (FIG. 5).
The axial fan 92 connected to the internal duct 91 is a fan that sucks air through the internal duct 91 and flows it in the direction of the rotation axis of the fan. The exhaust duct 93 connected to the axial fan 92 is disposed opposite to the exhaust port 17 of the exterior case 2 and rectifies the air flowing from the axial fan 92 and discharges it to the outside.

A cooling structure inside the projector 1 by the cooling unit 7 will be described.
FIGS. 16 and 17 are diagrams showing cooling flow paths formed inside the projector 1.
As shown in FIGS. 16 and 17, the projector 1 has a panel / power supply cooling channel A for mainly cooling the liquid crystal panels 441R, 441G, and 441B and the power supply unit 6, and polarization conversion. A polarization conversion element cooling channel B that mainly cools the element 414 and a light source cooling channel C that mainly cools the light source device 411 are formed.
The panel / power supply cooling channel A is formed by circulating cooling air through the projector 1 as shown below.
That is, as shown in FIG. 17, the external cooling air is sucked from the intake port 23 (FIG. 2) formed in the bottom surface portion 12 </ b> A of the outer case 2 by the sirocco fan 71 and is discharged to the intake side duct 72. Then, the cooling air is guided to the intake-side duct 72 and the light modulation devices 440R and 440G connected to the opening 451B2 from the opening 451B2 (FIG. 15) formed in the bottom surface portion of the optical component casing 45. , 440B connecting frames 83R, 83G, 83B and the bent portion 83R7 (the same applies to the connecting frames 83G, 83B) to the inside of the optical component housing 45.

The cooling air introduced into the optical component casing 45 is blown up between the incident side holding frames 82R, 82G, 82B of the liquid crystal panels 441R, 441G, 441B and the emission side holding frames 81R, 81G, 81B. The liquid crystal panels 401R, 401G, and 401B are sufficiently cooled from the upstream side to the downstream side, and the incident side polarizing plate 442, the viewing angle correction plate 443, and the emission side polarizing plate 444 are cooled while the optical device 44 It flows from the bottom to the top and flows out of the optical component casing 45 as shown in FIG. The air that has flowed out of the optical component housing 45 is attracted by the sirocco fan 73 and cools the control board (not shown) disposed on the projection lens 3 side above the optical unit 4. And is introduced into the power supply block 61.
The air introduced into the power supply block 61 flows along the cylindrical member 612 while cooling the circuit elements mounted on the internal circuit board 611, is sucked into the sirocco fan 73, and enters the inside of the light source drive block 62. And discharged. The air discharged into the light source drive block 62 is drawn by the axial fan 92 of the exhaust mechanism 90 and flows along the cylindrical member 622 while cooling the circuit elements mounted on the circuit board (not shown). The air is sucked into the exhaust mechanism 90. Then, as shown in FIG. 16, the air is rectified in the direction away from the projection direction by the exhaust side duct 93 and discharged from the exhaust port 17 of the exterior case 2.

The polarization conversion element cooling channel B is formed by the cooling air flowing through the projector 1 as shown below.
That is, the external cooling air is sucked from the intake port 23 (FIG. 2) formed in the bottom surface portion 12 </ b> A of the outer case 2 by the sirocco fan 71 and discharged to the intake side duct 72 as shown in FIG. 16. Then, the cooling air is introduced into the optical component casing 45 from the opening 451B3 (FIG. 15) formed in the bottom surface portion of the optical component casing 45 by being guided to the intake duct 72. Then, the cooling air introduced into the optical component casing 45 cools the polarization conversion element 414 and, as shown in FIG. 17, the optical component casing 45 from the opening 452A formed in the lid-like member 452. It flows out to the outside.

The light source cooling channel C is formed by circulating cooling air through the projector 1 as shown below.
That is, a part of the cooling air flowing through the panel / power supply cooling channel A and the cooling air flowing through the polarization conversion element cooling channel B are drawn by the exhaust mechanism 90 as shown in FIG. It enters between the light source storage part 451A of the housing 45 and is introduced into the light source storage part 451A from an opening (FIG. 4) formed on the rear side end face of the light source storage part 451A. The air introduced into the light source storage unit 451A cools the light source device 411 and is sucked by the exhaust mechanism 90 through an opening (not shown) formed in the front end surface of the light source storage unit 451A. The air sucked by the exhaust mechanism 90 is rectified in a direction away from the projection direction by the exhaust side duct 93 and discharged from the exhaust port 17 of the exterior case 2.

The present invention is not limited to the above-described embodiments, and includes modifications as described below.
The shapes, materials, fixing modes, and the like of the emission side holding frames 81R, 81G, 81B, the incident side holding frames 82R, 82G, 82B, and the connection frames 83R, 83G, 83B are not limited to those of the above embodiment. The incident-side holding frame and the emission-side holding frame do not have to be in direct contact with the light modulation element. In the above embodiment, the emission-side holding frames 81R, 81G, 81B are crossed via the fixing plates 446R, 446G, 446B. Although the dichroic prism 445 is fixed, the exit side holding frames 81R, 81G, and 81B may be directly fixed to the cross dichroic prism 445. That is, if it is arranged on the incident side and the emission side of the light modulation element and is thermally conductively connected to each other by the connection frame, the improvement of the heat radiation performance and the cooling performance, which are the objects of the present invention, can be realized.

Further, the shape of the rectifying portion 83R6 and the bent portion 83R7 is not limited to that of the above embodiment, and the end portion of the bent portion 83R7 may not be connected to the opening 451B2.
Furthermore, the flow of the cooling air does not need to flow in the direction of blowing up the inside of the connection frame, and may flow in the direction of blowing down.

The optical device of the present invention is not limited to the so-called three-plate type as described above, and may be configured as a so-called single-plate type optical device using a light modulation element such as a single liquid crystal panel.
Further, the light modulation device and the optical device of the present invention can be applied to a rear projection projector in addition to the front projection projector as described above.

  The present invention can be used not only for projectors but also for other optical devices.

1 is a schematic diagram showing the structure of a projector according to a first embodiment of the invention. The perspective view which looked at the projector in the said embodiment from the downward front side. The perspective view which looked at the projector in the said embodiment from the back back side. The figure which shows the internal structure of the projector in the said embodiment. The figure which shows typically the optical system of the optical unit in the said embodiment. The perspective view which looked at the optical apparatus in the said embodiment from upper direction. The perspective view which looked at the optical apparatus in the said embodiment from the downward direction. The perspective view which looked at the light modulation apparatus in the said embodiment from the light beam entrance side (at the time of the injection | emission side holding frame attachment). The perspective view which looked at the light modulation apparatus in the said embodiment from the light beam emission side (at the time of an emission side holding frame attachment). The perspective view which looked at the light modulation apparatus in the said embodiment from the light beam entrance side (at the time of attachment of an incident side holding frame and an emission side holding frame). The perspective view which looked at the light modulation apparatus in the said embodiment from the light beam emission side (at the time of incident side holding frame and emission side holding frame attachment). The perspective view which looked at the light modulation apparatus in the said embodiment from the light beam entrance side (at the time of attachment of an incident side holding frame, an emission side holding frame, and a connection frame). The perspective view which looked at the light modulation device in the said embodiment from the light beam emission side (at the time of incident side holding frame, emission side holding frame, and connection frame attachment). The figure explaining the structure of the cooling unit in the said embodiment. The figure explaining the structure of the cooling unit in the said embodiment. The figure which shows the cooling flow path formed inside the projector in the said embodiment. The figure which shows the cooling flow path formed inside the projector in the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Projector, 81R, 81G, 81B ... Ejection side holding frame, 81R1 ... Opening part, 82R, 82G, 82B ... Incident side holding frame, 82R1 ... Opening part, 83R, 83G, 83B ... Connection frame, 83R3 ... Connection part, 83R6: Rectifying part (rectifying member), 83R7: Bent part, 411 ... Light source device, 440R, 440G, 440B ... Light modulation device, 441R, 441G, 441B ... Liquid crystal panel (light modulation element), 451B2 ... Opening part (blow-off port) ).

Claims (8)

A light modulation device including a light modulation element that modulates an incident light beam according to image information to form an optical image,
An opening formed at a position corresponding to an image forming region of the light modulation element is formed, and an incident side holding frame that holds the light modulation element from a light beam incident side;
An exit side holding frame that has an opening formed at a position corresponding to the opening of the incident side holding frame, is combined with the incident side holding frame, and holds the light modulation element from a light beam exit side;
One end of the incident side holding frame and the exit side holding frame, and the other end of the incident side holding frame and the exit side holding frame facing the end are connected to each other so as to be capable of conducting heat, and A light modulation device comprising a connecting frame for guiding cooling air for cooling the light modulation element between the end portions. The light modulation device according to claim 1,
The light modulator according to claim 1, wherein the connecting frame is made of a heat conductive material. The light modulation device according to claim 1 or 2,
The light modulating device according to claim 1, wherein a rectifying member extending along the flow of the cooling air is provided at a position corresponding to each end to be connected to the connection frame. The light modulation device according to claim 3.
The light modulation device, wherein the rectifying members are bent so as to approach each other toward the upstream side of the cooling air. In the light modulation device according to any one of claims 1 to 4,
The connection frame includes a connection portion that connects the one end portion and a connection portion that connects the other end portion so as to allow heat conduction at a position on the downstream side of the cooling air. A light modulation device characterized by the above. The light modulation device according to any one of claims 1 to 5,
A light modulation device, wherein a heat conductive elastic material is interposed between the incident side holding frame, the emission side holding frame, and the connection frame. A light modulation device having a light modulation element for modulating an incident light beam according to image information to form an optical image, and a light beam incident end face facing the light modulation device, and formed by the light modulation device An optical device comprising a color combining optical device for combining optical images,
The optical device according to claim 1, wherein the optical modulator is the optical modulator according to claim 1. A projector that modulates a light beam emitted from a light source according to image information to form an optical image, and projects an enlarged image.
A projector comprising the optical device according to claim 7.

Images