JP2007199279A - Projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly reliable projector by restraining thermal degradation of optical modulation element. <P>SOLUTION: An optical modulation device 441 constituting the projector is equipped with: a liquid crystal panel 4411 modulating luminous flux emitted from a light source device according to image information; and an optical modulation element holding frame 4412 having aperture parts 4413A and 4414A corresponding to the image forming area of the liquid crystal panel 4411 and allowing the luminous flux to pass through, and holding the liquid crystal panel 4411. A reflection surface 4413D reflecting the luminous flux coming off from the image forming area out of the luminous flux made incident on the optical modulation device 441 is provided on the luminous flux incident side of the optical modulation device 441. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a projector.

2. Description of the Related Art Conventionally, there is known a projector including a light source device, a light modulation device that modulates a light beam emitted from the light source device according to image information, and a projection optical device that enlarges and projects the light beam modulated by the light modulation device. (For example, refer to Patent Document 1).
In the projector described in Patent Document 1, a liquid crystal panel unit (light modulation device) includes a liquid crystal panel (light modulation element) and a rectangular opening that allows a light beam incident on the liquid crystal panel to pass therethrough. It consists of a panel frame (light modulation element holding frame) for storing and holding.

JP 2000-221588 A

By the way, when irradiating a light beam from the light source device to the liquid crystal panel, a large margin is provided for a predetermined margin with respect to the image forming area of the liquid crystal panel so that the light beam is irradiated to the entire image forming area of the liquid crystal panel. The optical design is such that the liquid crystal panel is irradiated with a light beam.
For this reason, the light beam emitted from the light source device is irradiated not only on the liquid crystal panel but also on the panel frame. Therefore, the panel frame body is irradiated with light, which causes heat generation of the panel frame body, and hence a temperature increase of the liquid crystal panel. That is, the liquid crystal panel may be thermally deteriorated due to the temperature rise of the liquid crystal panel.

  An object of the present invention is to provide a highly reliable projector that suppresses thermal degradation of a light modulation element.

A projector according to the present invention includes a light source device, a light modulation device that modulates a light beam emitted from the light source device according to image information, and a projection optical device that enlarges and projects the light beam modulated by the light modulation device. A light modulation device that modulates a light beam emitted from the light source device according to image information; and a light beam that corresponds to an image forming area of the light modulation device. And a light modulation element holding frame that holds the light modulation element, and the light incident side of the light modulation device is out of the image forming area of the light flux incident on the light modulation device. A reflection surface for reflecting the light beam is provided.
Here, the reflection surface only needs to be provided on the light beam incident side of the light modulation device. For example, a reflection member is provided separately from the configuration formed on the light beam incident side end surface of the light modulation element holding frame or the light modulation device. A configuration in which a reflecting surface is provided on the reflecting member can be employed.
According to the present invention, since the reflecting surface is provided on the light beam incident side of the light modulation device, the light beam is irradiated toward the light modulation element in a large illumination area by a predetermined margin with respect to the image forming area. In addition, a light beam that is out of the image forming area out of the light beam incident on the light modulation device can be reflected by the reflecting surface. For this reason, it can be avoided that the light modulation element holding frame generates heat due to unnecessary light that does not contribute to image formation and the temperature of the light modulation element rises. Therefore, thermal deterioration of the light modulation element is suppressed, and the reliability of the projector is improved.

In the projector according to the aspect of the invention, it is preferable that the reflection surface is formed on a light beam incident side end surface of the light modulation element holding frame.
According to the present invention, since the reflection surface is formed on the light incident side end face of the light modulation element holding frame, even when a light beam is incident on the light modulation element holding frame, it is reflected by the reflection surface and held by the light modulation element. Light absorption into the frame can be prevented, and heat generation of the light modulation element holding frame can be suppressed.
Further, it is not necessary to provide a reflecting member or the like separately from the light modulation device, and the projector can be reduced in size and cost.

In the projector according to the aspect of the invention, it is preferable that a reflection member having the reflection surface is disposed on a light beam incident side of the light modulation device.
According to the present invention, since the reflection member is disposed on the light beam incident side of the light modulation device, the light beam that is out of the image forming area out of the light beam incident on the light modulation device is reflected by the reflection surface formed on the reflection member. Can be reflected.
In addition, since the reflection member is provided separately from the light modulation device, for example, the reflection surface absorbs a part of the light beam outside the image forming region as compared with the configuration in which the reflection surface is formed on the light modulation element holding frame. Even if it is a case, it can suppress that the heat | fever is transmitted to a light modulation element.

In the projector according to the aspect of the invention, it is preferable that the reflecting member is integrally connected to a light beam incident side end surface of the light modulation element holding frame.
By the way, since the light beam emitted from the light source device is irradiated to the image forming area of the light modulation element, the temperature of the light modulation element rises. For this reason, a structure for cooling the light modulation element is required. Conventionally, a structure in which the light modulation element is cooled by blowing cooling air to the light modulation element or sucking air in the vicinity of the light modulation element is often used. In addition, when such a cooling structure is adopted, the cooling air is blown well to the light modulation element or the air in the vicinity of the light modulation element is sucked well, so that the light flux of the light modulation element A predetermined space is required on the incident side or the light beam exit side. In recent years, miniaturization of projectors has been promoted, and optical components are also arranged in a dense state. For this reason, it is difficult to arrange the reflecting member on the light beam incident side of the light modulation device so that the predetermined space is formed. When the reflection member is forcibly arranged at a predetermined interval, the light modulation element is good. Difficult to cool down.
According to the present invention, since the reflecting member is integrally connected to the light beam incident side end face of the light modulation element holding frame, the predetermined space is provided on the light beam incident side (light beam incident side of the reflecting member) of the light modulation device. The cooling air can be blown well to the light modulation element, or the air in the vicinity of the light modulation element can be sucked well, and the cooling structure of the light modulation element can be maintained well.

In the projector according to the aspect of the invention, it is preferable that the light modulation element holding frame and the reflection member are made of a material having thermal conductivity and are connected to each other so as to be able to transfer heat.
According to the present invention, since the light modulation element holding frame and the reflection member are made of a material having thermal conductivity and are connected to each other so as to be able to transfer heat, light emitted from the light source device is irradiated with light. The heat generated in the modulation element can be dissipated by following the heat transfer path from the light modulation element to the light modulation element holding frame to the reflection member. For this reason, if the cooling structure of the light modulation element described above is used in combination, the light modulation element can be cooled more effectively, and thermal deterioration of the light modulation element can be effectively suppressed. In addition, for example, compared with a configuration in which the light modulation element holding frame and the reflection member are arranged in a state of being spaced apart by a predetermined distance, the heat dissipation area of heat transferred from the light modulation element can be increased, and the light modulation element The cooling efficiency can be improved.

In the projector according to the aspect of the invention, the reflection surface may be inclined at a predetermined angle with respect to a plane orthogonal to the optical axis of the light beam incident on the light modulation device, and the image out of the light beam incident on the light modulation device. It is preferable to reflect the light beam outside the formation region in a direction to avoid the optical element disposed on the optical path upstream side of the light modulation device.
By the way, in the case where a light beam that is outside the image forming area is reflected by the reflecting surface among the light beams that enter the light modulation device, the reflected light beam enters the optical element disposed on the front side of the optical path of the light modulation device. As the element absorbs the reflected light, the temperature rises and the reliability is affected.
According to the present invention, by forming the reflecting surface as described above, the light beam that is out of the image forming area among the light beams incident on the light modulation device is disposed on the reflection surface on the upstream side of the optical path of the light modulation device. It is reflected in the direction that avoids the optical element. For this reason, the light beam reflected by the reflecting surface does not enter the optical element arranged on the front side of the optical path of the light modulation device, and the temperature rise of both the light modulation device and the optical element can be suppressed. Can improve the reliability.

In the projector according to the aspect of the invention, the reflecting surface may have a planar frame shape surrounding the image forming region in a plane, and a light beam incident on the light modulation device may be formed on a peripheral edge portion of the frame shape on the reflecting surface. It is preferable that a non-interference surface that is inclined in the light beam emission direction with respect to a plane orthogonal to the optical axis is formed.
By the way, the light beam irradiated from the light source device to the image forming area of the light modulation element is irradiated to the image forming area with a predetermined spread. That is, in addition to the light beam that is vertically incident toward the image forming area, there is a light beam that is obliquely incident from the outside of the image forming area toward the image forming area. Here, when the peripheral edge of the frame-shaped opening on the reflecting surface is formed in a plane perpendicular to the optical axis of the light beam incident on the light modulation device, for example, the obliquely incident light beam is also reflected on the reflecting surface. Will be shaded. In such a case, the luminous flux contributing to the image formation is shielded, and the luminance of the image is lowered.
According to the present invention, a non-interference surface that is inclined in the light beam emission direction with respect to a plane perpendicular to the optical axis of the light beam incident on the light modulation device is formed on the peripheral edge portion of the frame-shaped opening on the reflection surface. The obliquely incident light beam is not shielded by the reflecting surface and is irradiated toward the image forming area. For this reason, the luminous flux contributing to image formation is not shielded, and the brightness of the image can be maintained satisfactorily.

A projector according to the present invention includes a light source device, a light modulation device that modulates a light beam emitted from the light source device according to image information, and a projection optical device that enlarges and projects the light beam modulated by the light modulation device. A light modulation device that modulates a light beam emitted from the light source device according to image information; and a light beam that corresponds to an image forming area of the light modulation device. A light modulation element holding frame that holds the light modulation element, and the light incident side of the light modulation device is out of the image forming area of the light flux incident on the light modulation device. An absorbing member that absorbs the luminous flux is provided.
According to the present invention, since the absorbing member is disposed on the light beam incident side of the light modulation device, the light beam is irradiated toward the light modulation element in a large illumination area by a predetermined margin with respect to the image forming area. At this time, of the light flux incident on the light modulation device, the light flux outside the image forming area can be absorbed by the absorbing member. For this reason, it can be avoided that the light modulation element holding frame generates heat due to unnecessary light that does not contribute to image formation and the temperature of the light modulation element rises. Therefore, thermal degradation of the light modulation element can be suppressed. Further, for example, if the absorbing member and the light modulation element holding frame are arranged in a thermally insulated state, it is possible to avoid the heat due to light absorption of the absorption member being transmitted to the light modulation element.

In the projector according to the aspect of the invention, the absorbing member may have a planar frame shape surrounding the image forming region in a plane, and a light beam incident on the light modulation device may be formed in a frame-shaped opening peripheral portion of the absorbing member. It is preferable that a non-interference surface that is inclined in the light beam emission direction with respect to a plane orthogonal to the optical axis is formed.
By the way, the light beam irradiated from the light source device to the image forming area of the light modulation element is irradiated to the image forming area with a predetermined spread. That is, in addition to the light beam that is vertically incident toward the image forming area, there is a light beam that is obliquely incident from the outside of the image forming area toward the image forming area. Here, in the case where the peripheral edge portion of the opening in the absorbing member is formed in, for example, a plane orthogonal to the optical axis of the light beam incident on the light modulation device, the obliquely incident light beam is also shielded by the absorbing member. End up. In such a case, the luminous flux contributing to the image formation is shielded, and the luminance of the image is lowered.
According to the present invention, a non-interfering surface that is inclined in the light beam emission direction with respect to a plane perpendicular to the optical axis of the light beam incident on the light modulation device is formed at the peripheral edge of the frame-shaped opening of the absorbing member. The obliquely incident light beam is not shielded by the absorbing member and is irradiated toward the image forming area. For this reason, the luminous flux contributing to image formation is not shielded, and the brightness of the image can be maintained satisfactorily.

[First embodiment]
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment of the invention will be described with reference to the drawings.
[Configuration of projector]
FIG. 1 is a diagram schematically showing a schematic configuration of a projector 1 in the first embodiment.
The projector 1 modulates a light beam emitted from a light source according to image information to form an optical image, and enlarges and projects the formed optical image on a screen (not shown). As shown in FIG. 1, the projector 1 includes an exterior housing 2, a projection lens 3 as a projection optical device, an optical unit 4, and the like.
Although not shown in FIG. 1, in the exterior casing 2, a space other than the projection lens 3 and the optical unit 4 is provided in a cooling unit constituted by a cooling fan or the like that cools the inside of the projector 1. It is assumed that a power supply unit that supplies electric power to each of the components and a control device that controls the entire projector 1 are arranged.

The exterior housing 2 is made of a synthetic resin or the like, and is formed in a substantially rectangular parallelepiped shape in which the projection lens 3 and the optical unit 4 are housed and disposed inside as shown in FIG. Although not shown, the exterior housing 2 is composed of an upper case that constitutes the top, front, back, and side surfaces of the projector 1 and a lower case that constitutes the bottom, front, and back surfaces of the projector 1, respectively. The upper case and the lower case are fixed to each other with screws or the like.
The exterior casing 2 is not limited to a synthetic resin, but may be formed of other materials, for example, a metal or the like.

The optical unit 4 is a unit that optically processes a light beam emitted from a light source under the control of the control device to form image light (color image) corresponding to image information. As shown in FIG. 1, the optical unit 4 has a substantially L shape in plan view extending along the back surface of the exterior housing 2 and extending along the side surface of the exterior housing 2. The detailed configuration of the optical unit 4 will be described later.
The projection lens 3 enlarges and projects the image light (color image) formed by the optical unit 4 onto a screen (not shown). The projection lens 3 is configured as a combined lens in which a plurality of lenses are housed in a cylindrical lens barrel.

[Detailed configuration of optical unit]
As shown in FIG. 1, the optical unit 4 houses and arranges the illumination optical device 41, the color separation optical device 42, the relay optical device 43, the optical device 44, and these optical components 41 to 44 inside. And an optical component housing 45 that supports and fixes the projection lens 3 at a predetermined position.
The illumination optical device 41 is an optical system for illuminating an image forming region of a light modulation device (liquid crystal panel), which will be described later, constituting the optical device 44 substantially uniformly. As shown in FIG. 1, the illumination optical device 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.

  As shown in FIG. 1, the light source device 411 includes a light source lamp 416 that emits a radial light beam, a reflector 417 that reflects the emitted light emitted from the light source lamp 416 and converges the light to a predetermined position, and the reflector 417 converges the light. And a collimating concave lens 418 that collimates the luminous flux with respect to the illumination optical axis A. As the light source lamp 416, a halogen lamp, a metal halide lamp, or a high-pressure mercury lamp is frequently used. Further, the reflector 417 is composed of an ellipsoidal reflector having a spheroidal surface, but may be composed of a parabolic reflector having a rotational paraboloid. In this case, the collimating concave lens 418 is omitted.

The first lens array 412 has a configuration in which small lenses having a substantially rectangular outline when viewed from the optical axis direction are arranged in a matrix. Each small lens splits the light beam emitted from the light source device 411 into a plurality of partial light beams.
The second lens array 413 has substantially the same configuration as the first lens array 412, and has a configuration in which small lenses are arranged in a matrix. The second lens array 413, together with the superimposing lens 415, has a function of forming an image of each small lens of the first lens array 412 on an image forming area of a light modulation device (liquid crystal panel) described later of the optical device 44. ing.

The polarization conversion element 414 is disposed between the second lens array 413 and the superimposing lens 415, and converts light from the second lens array 413 into substantially one type of polarized light.
Specifically, each partial light converted into substantially one type of polarized light by the polarization conversion element 414 is finally applied to an image forming region of a light modulation device (liquid crystal panel) described later of the optical device 44 by the superimposing lens 415. Superimposed. In a projector using a liquid crystal panel of a type that modulates polarized light, only one type of polarized light can be used, and therefore approximately half of the light from the light source device 411 that emits randomly polarized light cannot be used. For this reason, by using the polarization conversion element 414, the light emitted from the light source device 411 is converted into substantially one type of polarized light, and the light use efficiency in the optical device 44 is increased.

FIG. 2 is a plan view schematically showing an illumination area superimposed on the liquid crystal panel by the illumination optical device 41.
As shown in FIG. 2, the illumination optical device 41 described above applies to the image forming area FA of the liquid crystal panel so that the light beam emitted from the light source device 411 is reliably irradiated to the entire image forming area FA of the liquid crystal panel. The optical design is such that the liquid crystal panel is irradiated with a light beam in a large illumination area IA by a predetermined margin M.

As shown in FIG. 1, the color separation optical device 42 includes two dichroic mirrors 421 and 422 and a reflection mirror 423, and a plurality of partial light beams emitted from the illumination optical device 41 by the dichroic mirrors 421 and 422. It has a function of separating into three color lights of red, green and blue.
The relay optical device 43 includes an incident side lens 431, a relay lens 433, and reflection mirrors 432 and 434, and has a function of guiding the color light separated by the color separation optical device 42 to a light modulation device for red light. .

  At this time, the dichroic mirror 421 of the color separation optical device 42 transmits the red light component and the green light component of the light beam emitted from the illumination optical device 41 and reflects the blue light component. The blue light reflected by the dichroic mirror 421 is reflected by the reflection mirror 423, passes through the field lens 419, and reaches the light modulator for blue light. The field lens 419 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 419 provided on the light incident side of the other liquid crystal panels for green light and red light.

  Of the red 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 419, and reaches the light modulation device for green light. On the other hand, the red light passes through the dichroic mirror 422, passes through the relay optical device 43, and further passes through the field lens 419 to reach the light modulation device for red light. Note that the relay optical device 43 is used for red light because the optical path length of the red light is longer than the optical path lengths of the other color lights, thereby preventing a decrease in light use efficiency due to light diffusion or the like. It is to do. That is, this is to transmit the partial light beam incident on the incident side lens 431 to the field lens 419 as it is. The relay optical device 43 is configured to pass red light out of the three color lights, but is not limited thereto, and may be configured to pass blue light, for example.

  The optical device 44 modulates the three color lights emitted from the color separation optical device 42 according to image information, and combines the modulated color lights to form image light (color image). As shown in FIG. 1, the optical device 44 includes three light modulation devices 441 (a light modulation device for red light 441R and a light for green light) having a liquid crystal panel 4411 (see FIG. 3) as light modulation elements. The modulation device is 441G and the blue light modulation device is 441B), the incident-side polarizing plate 442 as three optical elements respectively disposed on the light beam incidence side of these light modulation devices 441, and each light modulation device 341 includes three exit-side polarizing plates 443 disposed on the light beam exit side of 441, and a cross dichroic prism 444 as a color synthesizing optical device. Of these, three light modulators 441, three exit-side polarizing plates 443, and a cross dichroic prism 444 are integrated, although not specifically shown. Note that the three incident-side polarizing plates 442 may be integrated in addition to the three light modulation devices 441, the three exit-side polarizing plates 443, and the cross dichroic prism 444.

The incident-side polarizing plate 442 receives light of each color whose polarization direction is aligned in approximately one direction by the polarization conversion element 414, and of the incident light beams, is substantially the same as the polarization axis of the light beams aligned by the polarization conversion element 414. Only polarized light in the direction is transmitted, and other light beams are absorbed. The incident-side polarizing plate 442 has a configuration in which, for example, a polarizing film 4422 (see FIG. 4) is attached to a translucent substrate 4421 (see FIG. 4) such as sapphire glass or quartz.
A liquid crystal panel 4411 constituting the light modulation device 441 has a configuration in which a liquid crystal as an electro-optical material is hermetically sealed between a pair of transparent glass substrates 4411A and 4411B (see FIG. 4), and a drive signal from the control device Accordingly, the alignment state of the liquid crystal is controlled, and the polarization direction of the polarized light beam emitted from the incident-side polarizing plate 442 is modulated. The liquid crystal panel 4411 is housed and held in a light modulation element holding frame 4412 (see FIG. 3). The specific configuration of the light modulation element holding frame 4412 will be described later.

The exit-side polarizing plate 443 has the same configuration as the incident-side polarizing plate 442, and has a polarization axis that is orthogonal to the transmission axis of the light flux in the incident-side polarizing plate 442 among the light beams emitted from the light modulation device 441. Only transmits light and absorbs other light fluxes. The exit-side polarizing plate 443 is attached to, for example, the end surface of the cross dichroic prism 444 on the light-incident side.
The cross dichroic prism 444 is an optical element that forms image light (color image) by combining modulated light modulated for each color light emitted from the emission-side polarizing plate 443. The cross dichroic prism 444 has a square shape in plan view in which four right angle prisms are bonded together, and two dielectric multilayer films are formed on the interface where the right angle prisms are bonded together. These dielectric multilayer films transmit the color light through the exit-side polarizing plate 443 arranged on the side facing the projection lens 3 (G color light side), and the remaining two exit-side polarizing plates 443 (R color light side and Each color light is reflected via the B color light side). In this way, the color lights modulated by the incident-side polarizing plates 442, the liquid crystal panels 4411, and the emission-side polarizing plates 443 are combined to form a color image.

[Configuration of light modulator]
FIG. 3 is an exploded perspective view showing the configuration of the light modulation device 441.
FIG. 4 is a cross-sectional view of the light modulation device 441 as viewed from above.
The three light modulation devices 441 have the same configuration, and only one light modulation device 441 will be described below.
As shown in FIG. 3 or 4, the light modulation device 441 includes a liquid crystal panel 4411 and a light modulation element holding frame 4412.
As shown in FIG. 3 or 4, the light modulation element holding frame 4412 includes a concave frame body 4413 having a substantially rectangular shape in a plan view that houses the liquid crystal panel 4411, and a liquid crystal panel 4411 housed in the concave frame body 4413. And a support plate 4414 having a substantially rectangular shape in plan view that is pressed and fixed to the concave frame 4413. As shown in FIG. 3 or FIG. 4, openings 4413 </ b> A and 4414 </ b> A corresponding to the image forming area of the liquid crystal panel 4411 are formed in the concave frame 4413 and the support plate 4414, respectively. . The liquid crystal panel 4411 is exposed at the openings 4413A and 4414A, modulates a light beam incident through the opening 4413A, and emits the light to the exit-side polarizing plate 443 through the opening 4414A.

The light modulation element holding frame 4412 can be formed by molding or sheet metal processing. In addition, as the material, for example, invar and iron-nickel alloy such as 42Ni-Fe, magnesium alloy, aluminum alloy, carbon steel, brass, stainless steel and other metals, or carbon filler such as carbon fiber and carbon nanotube are mixed. Resin (polycarbonate, polyphenylene sulfide, liquid crystal resin) or the like can be employed.
By configuring the light modulation element holding frame 4412 with the above-described material, the light modulation element holding frame 4412 and the liquid crystal panel 4411 are connected so that heat can be transferred when the liquid crystal panel 4411 is stored and held in the light modulation element holding frame 4412. The light emitted from the light source device 411 is irradiated onto the liquid crystal panel 4411 so that heat generated in the liquid crystal panel 4411 can be radiated to the light modulation element holding frame 4412. Therefore, the temperature rise of the liquid crystal panel 4411 is avoided.
In the present embodiment, as shown in FIG. 1, openings 451 are formed on the bottom surface of the optical component housing 45 at positions corresponding to the arrangement positions of the respective light modulation devices 441. Then, cooling air is blown from the cooling unit to each light modulator 441 through each opening 451, or air near each light modulator 441 is sucked by the cooling unit through each opening 451. By doing so, the temperature rise of the liquid crystal panel 4411 is avoided.

As shown in FIG. 4, the concave frame 4413 has a substantially U-shaped cross section, and a storage portion 4413B is provided inside the U-shape, and the liquid crystal panel 4411 is stored in the storage portion 4413B.
In the concave frame 4413, as shown in FIG. 3, the upper and lower corner ends do not interfere with a pin insertion portion (described later) of the support plate 4414 in a plan view when viewed from the U-shaped base end side. Cutout portions 4413C are respectively formed.

Further, in the concave frame 4413, the light incident on the light incident side end surface reflects a light beam that is out of the image forming area FA (FIG. 2) out of the light beam incident on the light modulation device 441, as shown in FIG. A reflecting surface 4413D is formed.
As shown in FIG. 3, the reflection surface 4413D has a substantially rectangular frame shape in plan view surrounding the opening 4413A in a plane. Then, as shown in FIG. 3 or FIG. 4, the reflecting surface 4413D is formed to be inclined at a predetermined angle with respect to a plane perpendicular to the optical axis A (FIG. 4) of the light beam incident on the light modulation device 441. The light beam L1 (FIG. 4) that deviates from the image forming area FA (FIG. 2) is reflected in a direction that avoids the incident-side polarizing plate 442 provided on the optical path upstream side of the light modulator 441.
In addition, as this reflective surface 4413D, when the concave frame 4413 is made of, for example, a metal material, the reflective surface 4413D is made to have the above-described shape, and then subjected to mirror finishing or the like, so that the reflective surface with high reflectivity is obtained. 4413D can be formed. In addition to forming the reflecting surface 4413D by mirror finishing or the like, the reflecting surface 4413D is formed into the shape described above, and then a highly reflective material such as a silver alloy is vapor-deposited uniformly. 4413D may be formed.
In the present embodiment, the reflecting surface 4413D is configured to have a reflectance of 70% or more.

  Further, in the concave frame 4413, the optical axis A (FIG. 4) of the light beam incident on the light modulator 441 is disposed at the peripheral edge of the rectangular frame-shaped opening on the reflection surface 4413D, as shown in FIG. A non-interference surface 4413E is formed which is inclined toward the light beam exit side with respect to a plane orthogonal to. In the present embodiment, the opening 4413A is formed so as to reduce in diameter toward the light beam exit side, and the inner side surface of the opening 4413A functions as the non-interference surface 4413E.

As shown in FIG. 3, the support plate 4414 is formed with pin insertion portions 4414B through which pin-like members (not shown) can be inserted at the four corner portions.
This pin insertion part 4414B is a burring hole formed so that the inner peripheral edge protrudes toward the light beam incident side.
Then, after the liquid crystal panel 4411 is stored in the storage portion 4413B of the concave frame body 4413, the support plate 4414 is attached to the light beam emission side end surface of the concave frame body 4413 with an adhesive or the like, so that the light modulation device 441 is integrated. It becomes. Further, while inserting four pin-shaped members (not shown) through the respective pin insertion portions 4414B of the support plate 4414, for example, the end portions of the respective pin-shaped members are bonded and fixed to the light beam incident side end surface of the cross dichroic prism 444, and The light modulation device 441 is integrated with the cross dichroic prism 444 by bonding and fixing the outer periphery of each pin-shaped member to the inner periphery of each pin insertion portion 4414B.

The first embodiment described above has the following effects.
In the present embodiment, since the reflection surface 4413D is provided on the light beam incident side of the light modulation device 441, the light beam is directed toward the liquid crystal panel 4411 in the large illumination area IA by a predetermined margin M with respect to the image forming area FA. When irradiated, the light beam L1 that is out of the image forming area FA out of the light beam incident on the light modulation device 441 can be reflected by the reflecting surface 4413D. For this reason, it can be avoided that the light modulation element holding frame 4412 generates heat due to unnecessary light that does not contribute to image formation and the liquid crystal panel 4411 rises in temperature. Therefore, thermal deterioration of the liquid crystal panel 4411 can be suppressed, reliability can be improved, and the life of the projector 1 can be extended.

Here, since the reflection surface 4413D is formed on the light beam incident side end surface of the light modulation element holding frame 4412, even when the light beam enters the light modulation element holding frame 4412, the light modulation element is reflected by the reflection surface 4413D. Light absorption to the holding frame 4412 can be prevented and heat generation of the light modulation element holding frame 4412 can be suppressed.
Further, it is not necessary to provide a reflecting member having a reflecting surface separately from the light modulation device 441, and the projector 1 can be reduced in size and cost.

By the way, when the light beam L1 that is out of the image forming area FA out of the light beam incident on the light modulation device 441 is reflected by the reflecting surface 4413D, when the reflected light beam enters the incident-side polarizing plate 442, the incident-side polarizing plate 442 is The reflected light flux is absorbed and the temperature rises.
In the present embodiment, the reflecting surface 4413D is formed to be inclined at a predetermined angle with respect to a plane orthogonal to the optical axis A of the light beam incident on the light modulation device 441. Therefore, the light beam incident on the light modulation device 441 is reflected. Of these, the light beam L1 outside the image forming area FA is reflected in a direction avoiding the incident-side polarizing plate 442 by the reflecting surface 4413D. For this reason, the light beam reflected by the reflecting surface 4413D does not enter the incident-side polarizing plate 442, and it is possible to prevent the incident-side polarizing plate 442 from increasing in temperature and to improve the reliability of the projector 1.

Incidentally, the light beam irradiated from the light source device 411 to the image forming area FA of the liquid crystal panel 4411 is irradiated to the image forming area with a predetermined spread. That is, in addition to the light beam that is vertically incident toward the image forming area FA, there is also a light beam L2 (FIG. 4) that is obliquely incident from the outside of the image forming area FA toward the image forming area. Here, in the case where the frame-shaped opening peripheral edge portion of the reflection surface 4413D is formed in a planar shape orthogonal to the optical axis A of the light beam incident on the light modulation device 441, for example, the obliquely incident light beam L2 is also The light is shielded by the reflection surface 4413D. In such a case, the light flux L2 that contributes to image formation is shielded, and the brightness of the image is reduced.
In the present embodiment, a non-interference surface 4413E that is inclined in the light beam emission direction with respect to a plane perpendicular to the optical axis A of the light beam incident on the light modulation device 441 is formed on the peripheral edge portion of the frame-shaped opening on the reflection surface 4413D. Therefore, the obliquely incident light beam L2 is not shielded by the reflecting surface 4413D and is irradiated toward the image forming area FA. For this reason, the brightness | luminance of an image can be maintained favorable, without light-shielding the light beam L2 which contributes to image formation.

[Second Embodiment]
Next, 2nd Embodiment of this invention is described based on drawing.
In the following description, the same structure and the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted or simplified.
FIG. 5 is a perspective view showing the structure and arrangement position of the reflecting member 445 in the second embodiment.
FIG. 6 is a cross-sectional view of the reflecting member 445 and the light modulation device 441 according to the second embodiment viewed from above in an integrated state.
In the first embodiment, a light beam that deviates from the image forming area FA out of the light beam directed to the light modulation device 441 is reflected by the reflecting surface 4413D formed on the light beam incident side end surface of the light modulation element holding frame 4412.
On the other hand, in the second embodiment, as shown in FIG. 5 or FIG. 6, the reflecting member 445 is arranged on the light beam incident side (between the light modulating device 441 and the incident side polarizing plate 442) of each light modulating device 441. And the light beams that deviate from the image forming area FA out of the light beams directed to the respective light modulation devices 441 are reflected by the respective reflection surfaces 4452 of the respective reflection members 445.
The configuration other than providing the three reflecting members 445 is the same as that in the first embodiment.
Further, the three reflecting members 445 disposed on the light beam incident side of the three light modulation devices 441 have the same configuration, and only one reflecting member 445 will be described below.

Specifically, as shown in FIG. 5 or FIG. 6, the reflecting member 445 has an opening 4451 corresponding to the image forming area of the liquid crystal panel 4411 and allowing the light beam to pass therethrough, and has a substantially rectangular frame shape in plan view. Have
In the reflecting member 445, the end surface on the light beam exit side has a shape that follows the end surface on the light beam entrance side of the light modulation element holding frame 4412 as shown in FIG. Then, as shown in FIG. 6, the reflection member 445 is bonded and fixed to the light incident side end surface of the light modulation element holding frame 4412 via, for example, an adhesive having thermal conductivity, and the light modulation element holding frame 4412 and the thermal modulation element holding frame 4412 are heated. Connect to communicate.

Further, in the reflecting member 445, the light incident side end face reflects the light beam that is out of the image forming area FA (FIG. 2) out of the light beam incident on the light modulation device 441, as shown in FIG. 5 or FIG. A surface 4452 is formed.
The reflective member 445 described above can be formed by molding or sheet metal processing, and the same material as the light modulation element holding frame 4412 can be adopted.
As shown in FIG. 5, the reflecting surface 4452 has a substantially rectangular frame shape in plan view surrounding the opening 4451 in a planar manner. Then, as shown in FIG. 5 or FIG. 6, the reflecting surface 4452 is formed to be inclined at a predetermined angle with respect to a plane perpendicular to the optical axis A (FIG. 6) of the light beam incident on the light modulation device 441. The light beam L1 (FIG. 6) that deviates from the image forming area FA (FIG. 2) is reflected in a direction that avoids the incident side polarizing plate 442 disposed on the upstream side of the optical path of the light modulator 441.
And as this reflective surface 4452, like the reflective surface 4413D explained in the first embodiment, when the reflective member 445 is made of, for example, a metal material, the reflective surface 4452 is shaped as described above, If a mirror finish or the like is applied, a reflective surface 4452 having a high reflectance can be formed. In addition to forming the reflecting surface 4442 by mirror finishing or the like, the reflecting surface 4452 is shaped as described above, and then a highly reflective material such as a silver alloy is vapor-deposited uniformly. 4452 may be formed.
In the present embodiment, the reflecting surface 4452 is configured to have a reflectance of 70% or more.

  Further, in the reflection member 445, the rectangular frame-shaped opening peripheral portion of the reflection surface 4452 is orthogonal to the optical axis A (FIG. 6) of the light beam incident on the light modulation device 441 as shown in FIG. A non-interference surface 4453 that is inclined toward the light beam emission side (inclined so as to be reduced in diameter toward the light beam emission side) with respect to the flat surface is formed. In this embodiment, the opening 4451 is formed so as to reduce in diameter toward the light beam exit side, and the inner side surface of the opening 4451 functions as the non-interference surface 4453.

According to the second embodiment described above, there are the following effects in addition to substantially the same effects as the first embodiment.
In the present embodiment, since the reflection member 445 is disposed on the light beam incident side of the light modulation device 441, the image forming region of the light beam incident on the light modulation device 441 is reflected by the reflection surface 4452 formed on the reflection member 445. The light beam L1 that deviates from the FA can be reflected.
In addition, since the reflection member 445 is provided separately from the light modulation device 441, the image formation region is compared with the configuration in which the reflection surface 4413D is formed on the light modulation element holding frame 4412 as described in the first embodiment. Even when the reflection surface absorbs a part of the light beam L1 that deviates from the FA, the heat can be prevented from being transmitted to the liquid crystal panel 4411.

By the way, in this embodiment, as explained in the first embodiment, the cooling unit is directed toward the light modulators 441 via the openings 451 formed on the bottom surface of the optical component casing 45. A temperature rise of the liquid crystal panel 4411 is avoided by blowing cooling air or sucking air in the vicinity of each light modulator 441 by the cooling unit through each opening 451. Here, in such a cooling structure, the cooling air is blown well to the light modulation device 441, or the air in the vicinity of the light modulation device 441 is sucked well, so that the light flux incident on the light modulation device 441 is incident. A predetermined space is required on the side or the light beam exit side. In this embodiment, in order to reduce the size of the projector 1, the optical components 411 to 415, 419, 421 to 423, 431 to 434, and 441 to 444 are arranged densely. For this reason, it is difficult to dispose the reflecting member 445 on the light beam incident side of the light modulation device 441 so that the predetermined space is formed. When the reflection member 445 is forcibly disposed at a predetermined interval, the liquid crystal panel 4411 is disposed. It is difficult to cool well.
In the present embodiment, since the reflecting member 445 is integrally connected to the end surface of the light modulation element holding frame 4412 on the light beam incident side, the predetermined light beam is provided on the light beam incident side of the light modulation device 441 (the light beam incident side of the reflection member 445). The cooling air is favorably blown to the liquid crystal panel 4411 or the air in the vicinity of the liquid crystal panel 4411 is favorably sucked, and the cooling structure of the liquid crystal panel 4411 can be maintained satisfactorily.

  In addition, since the light modulation element holding frame 4412 and the reflection member 445 are made of a material having thermal conductivity and are connected so as to be able to transfer heat to each other, the liquid crystal panel is irradiated with the light emitted from the light source device 411. The heat generated in 4411 can be dissipated by following the heat transfer path of the liquid crystal panel 4411 to the light modulation element holding frame 4412 to the reflection member 445. For this reason, by using together the cooling structure of the liquid crystal panel 4411 mentioned above, the liquid crystal panel 4411 can be cooled more effectively and the thermal deterioration of the liquid crystal panel 4411 can be suppressed effectively. In addition, for example, compared to a configuration in which the light modulation element holding frame 4412 and the reflection member 445 are arranged in a state of being spaced apart by a predetermined interval, the heat dissipation area of heat transferred from the liquid crystal panel 4411 can be increased, The cooling efficiency of the panel 4411 can be improved.

[Third embodiment]
Next, 3rd Embodiment of this invention is described based on drawing.
In the following description, the same structure and the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted or simplified.
FIG. 7 is a perspective view showing the structure and arrangement position of the absorbing member 446 in the third embodiment.
FIG. 8 is a cross-sectional view of the absorbing member 446 and the light modulation device 441 in the third embodiment as viewed from above.
In the first embodiment, of the light beam toward the light modulation device 441, the light beam that deviates from the image forming area FA is reflected by the reflection surface 4413D.
On the other hand, in the third embodiment, as shown in FIG. 7 or FIG. 8, an absorbing member 446 is arranged on the light beam incident side (between the light modulating device 441 and the incident-side polarizing plate 442) of each light modulating device 441. The light absorbing member 446 absorbs the light beam L1 (FIG. 8) out of the image forming area FA out of the light beam directed to each light modulation device 441.
The configuration other than the point of providing the absorbing member 446 is the same as that of the first embodiment.
In addition, the three absorbing members 446 disposed on the light beam incident side of the three light modulators 441 have the same configuration, and only one absorbing member 446 will be described below.

Specifically, the absorbing member 446 is made of a material that absorbs the incident light beam, and has an opening 4461 that allows the light beam to pass through corresponding to the image forming area of the liquid crystal panel 4411 as shown in FIG. It is a plate body having a rectangular frame shape in plan view. The absorbing member 446 is disposed on the light beam incident side of the light modulation device 441 while being thermally insulated from the light modulation element holding frame 4412. In other words, the absorbing member 446 may be connected to the light modulation element holding frame 4412 via a heat insulating material, or disposed at a position spaced apart from the light modulation device 441 by a predetermined distance. Also good.
As a material of the absorbing member 446, for example, ceramic, aluminum subjected to alumite treatment, or the like can be used. The absorbing member 446 may be made of any material as long as it absorbs an incident light beam and has an absorptance of 50% or more, in addition to ceramic, anodized aluminum, or the like.

  Further, in the absorbing member 446, the light beam is provided at the periphery of the opening 4461 with respect to a plane perpendicular to the optical axis A (FIG. 8) of the light beam incident on the light modulation device 441, as shown in FIG. A non-interference surface 4462 that is inclined toward the emission side is formed. In this embodiment, the opening 4461 is formed so as to reduce in diameter toward the light beam exit side, and the inner surface of the opening 4461 functions as a non-interference surface 4462.

The third embodiment described above has the following effects.
In the present embodiment, since the absorbing member 446 is disposed on the light beam incident side of the light modulation device 441, the light beam is directed toward the liquid crystal panel 4411 in a large illumination area IA by a predetermined margin M with respect to the image forming area FA. Can be absorbed by the absorbing member 446, out of the image forming area FA out of the light beams incident on the light modulation device 441. For this reason, it can be avoided that the light modulation element holding frame 4412 generates heat due to unnecessary light that does not contribute to image formation and the liquid crystal panel 4411 rises in temperature. Therefore, thermal deterioration of the liquid crystal panel 4411 can be suppressed.
In addition, since the absorbing member 446 is disposed in a state of being thermally insulated from the light modulation element holding frame 4412, heat due to light absorption of the absorbing member 446 can be prevented from being transmitted to the liquid crystal panel 4411. .

  Further, since the non-interference surface 4462 similar to the non-interference surface 4413E described in the first embodiment is formed on the peripheral edge portion of the frame-shaped opening of the absorbing member 446, similarly to the first embodiment, The luminance of the image can be maintained well without blocking the light beam L2 that contributes to the formation of the image.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
In each of the above embodiments, the configuration of the light modulation element holding frame 4412 is not limited to the configuration described in each of the above embodiments, and may be any configuration as long as the liquid crystal panel 4411 can be held.
For example, in the first embodiment, the reflection surface 4413D may be formed on the light modulation element holding frame 4412. For example, each pin insertion portion 4414B is formed on the concave frame 4413, and the support plate 4414 is omitted. A configuration may be adopted. The same applies to the second embodiment and the third embodiment.
Further, for example, in the second embodiment and the third embodiment, the configuration of the light modulation device is the same as that of the first embodiment. That is, the light incident side end surface of the light modulation element holding frame is the optical axis. Although the shape is inclined at a predetermined angle with respect to A, the present invention is not limited to this, and the end surface on the light beam incident side of the light modulation element holding frame may be formed in a planar shape substantially perpendicular to the optical axis A. In such a configuration, in the second embodiment, the light beam emission side end surface of the reflecting member 445 may be formed in a planar shape so as to follow the light beam incident side end surface of the light modulation element holding frame.

  In each of the embodiments, the structure in which the light beam L1 is reflected by the reflecting surfaces 4413D and 4452 and the structure in which the light beam L1 is absorbed by the absorbing member 446 are provided on the three color light sides. You may employ | adopt the structure provided in at least any one among each color light side.

In the second embodiment, the shape of the reflecting member 445 is not limited to the shape described in the second embodiment.
For example, in the reflecting member 445, protruding portions that protrude from the left and right edges of the reflecting member 445 to the light beam emission side are formed and formed in a substantially U-shaped cross section. The light modulation device 441 is housed inside the U-shape of the reflecting member 445, and the light modulation device 441 is configured to be movable along the optical axis A inside the pair of protrusions. With this configuration, during the manufacture of the optical device 44, the position of the liquid crystal panel 4411 is adjusted by moving the light modulation device 441 along the optical axis A inside the pair of protrusions of the reflecting member. can do.

In each of the above embodiments, the projector 1 using the three light modulation devices 441 has been described. However, the present invention is not limited to this. For example, the invention can be applied to a projector using only one light modulation device, a projector using two light modulation devices, or a projector using four or more light modulation devices.
In each of the above embodiments, the transmissive liquid crystal panel 4411 is used as the light modulation element. However, the present invention is not limited to this, and a reflective liquid crystal panel may be used, or a digital micromirror device (Texas) -Trademark of Instrument Corporation) may be adopted.
In each of the above embodiments, the optical unit 4 has a substantially L shape in plan view, but other shapes may be employed, for example, a substantially U shape in plan view.
In each of the embodiments described above, only the example of the front type projector that projects from the direction of observing the screen has been described. However, in the present invention, the rear type projector that projects from the side opposite to the direction of observing the screen is also described. Applicable.

Although the best configuration for carrying out the present invention has been disclosed in the above description, the present invention is not limited to this. That is, the invention has been illustrated and described primarily with respect to particular embodiments, but it is not intended to depart from the technical concept and scope of the invention. Various modifications can be made by those skilled in the art in terms of materials, quantity, and other detailed configurations.
Therefore, the description limited to the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such restrictions is included in this invention.

  The present invention can be used as a projector used for presentations, home theaters, and the like because it can suppress thermal deterioration of the light modulation element and improve reliability.

FIG. 2 is a diagram schematically illustrating a schematic configuration of a projector according to the first embodiment. The top view which shows typically the illumination area superimposed on a liquid crystal panel by the illumination optical apparatus in the said embodiment. The disassembled perspective view which shows the structure of the light modulation apparatus in the said embodiment. Sectional drawing which looked at the light modulation apparatus in the said embodiment from the upper side. The perspective view which shows the structure and arrangement | positioning position of the reflection member in 2nd Embodiment. Sectional drawing seen from the upper side in the state which integrated the reflection member and light modulation apparatus in the said embodiment. The perspective view which shows the structure and arrangement | positioning position of the absorption member in 3rd Embodiment. Sectional drawing which looked at the absorption member and light modulation apparatus in the said embodiment from the upper side.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Projector, 3 ... Projection lens (projection optical apparatus), 411 ... Light source device, 441, 441R, 441G, 441B ... Light modulation apparatus, 442 ... Incident side polarizing plate (optical element) 445 ... Reflective member, 446 ... Absorbing member, 4411 ... Liquid crystal panel (light modulation element), 4412 ... Light modulation element holding frame, 4413A, 4414A ... Opening, 4413D, 4452 ... reflective surface, 4413E, 4453, 4462 ... non-interference surface, FA ... image forming area.

Claims (9)

A projector comprising: a light source device; a light modulation device that modulates a light beam emitted from the light source device according to image information; and a projection optical device that enlarges and projects the light beam modulated by the light modulation device. ,
The light modulation device includes a light modulation element that modulates a light beam emitted from the light source device in accordance with image information, and an opening that allows the light beam to pass through corresponding to an image forming region of the light modulation element. A light modulation element holding frame for holding the light modulation element;
The projector according to claim 1, wherein a reflection surface is provided on a light beam incident side of the light modulation device to reflect a light beam incident on the light modulation device and deviating from the image forming area. The projector according to claim 1, wherein
The projector according to claim 1, wherein the reflection surface is formed on a light beam incident side end surface of the light modulation element holding frame. The projector according to claim 1, wherein
A projector having a reflecting member having the reflecting surface disposed on a light beam incident side of the light modulation device. The projector according to claim 3, wherein
The projector, wherein the reflecting member is integrally connected to a light beam incident side end face of the light modulation element holding frame. The projector according to claim 4, wherein
The projector, wherein the light modulation element holding frame and the reflection member are made of a material having thermal conductivity and are connected to each other so as to be able to transfer heat. The projector according to any one of claims 1 to 5,
The reflection surface is formed at a predetermined angle and inclined with respect to a plane perpendicular to the optical axis of the light beam incident on the light modulation device, and a light beam that is out of the image forming area out of the light beam incident on the light modulation device. A projector that reflects light in a direction that avoids an optical element disposed on the upstream side of the light modulation device. The projector according to any one of claims 1 to 6,
The reflective surface has a planar frame shape surrounding the image forming region in a plane,
A non-interfering surface that is inclined in the light beam emission direction with respect to a plane perpendicular to the optical axis of the light beam incident on the light modulation device is formed at a peripheral edge portion of the frame-shaped opening on the reflection surface. projector. A projector comprising: a light source device; a light modulation device that modulates a light beam emitted from the light source device according to image information; and a projection optical device that enlarges and projects the light beam modulated by the light modulation device. ,
The light modulation device includes a light modulation element that modulates a light beam emitted from the light source device in accordance with image information, and an opening that allows the light beam to pass through corresponding to an image forming region of the light modulation element. A light modulation element holding frame for holding the light modulation element;
The projector according to claim 1, wherein an absorbing member that absorbs a light beam that is out of the image forming area out of the light beam incident on the light modulation device is disposed on the light beam incident side of the light modulation device. The projector according to claim 8, wherein
The absorbing member has a planar view frame shape surrounding the image forming region in a plane,
A non-interference surface that is inclined in the light beam exit direction with respect to a plane perpendicular to the optical axis of the light beam incident on the light modulation device is formed at a peripheral edge portion of the frame-shaped opening of the absorbing member. projector.

Images