JP2005208482A - Optical apparatus and projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical apparatus and a projector which can surely attain the miniaturization, the reduction of a manufacturing cost and the facilitation of the manufacture, also, which is improved in terms of image quality, and also, which can be satisfactorily efficiently cooled. <P>SOLUTION: The optical apparatus 44 is provided with a plurality of optical modulators 440R, 440G and 440B for modulating a plurality of color light beams for every color light beam in accordance with image information and forming optical images, and a color compositing optical apparatus 443 having a plurality of luminous flux incident end faces and for compositing the optical images, and the apparatus is provided with pedestals 446 and 447 arranged on the end faces orthogonal to the plurality of luminous flux incident end faces and an adjusting member 700 which is inserted in between the pedestals 446 and 447 and the optical modulators 440R, 440G and 440B so as to adjust the positioning of the optical modulators 440R, 440G and 440B in a prescribed position, and also, slopes 446A and 447A inclined to the luminous flux incident end faces of the color compositing optical apparatus 443 are formed on the outer peripheral parts of the pedestals 446 and 447, and the adjusting member 700 is inserted along the slopes 446A and 447A. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention includes a plurality of light modulation devices that modulate a plurality of color lights according to image information for each color light to form an optical image, and a plurality of light flux incident end faces that face the light modulation devices. The present invention relates to an optical device including a color combining optical device that combines optical images formed by a modulation device, and a projector including the optical device.

Conventionally, projectors have been used for presentations at conferences, academic conferences, and exhibitions, and in recent years, they have also been used for home theaters.
As such a projector, a color separation optical system that separates a light beam emitted from a light source lamp into red, green, and blue color light using a dichroic mirror, and the separated light beam as image information for each color light. An optical device having three light modulation devices (liquid crystal panels) that modulate in response, a color combining optical device (cross dichroic prism) that combines light beams modulated by the liquid crystal panels, and a color formed by the optical device A three-plate projector having a projection lens for enlarging and projecting an optical image on a screen is known.

Such projectors have been developed to be lighter and more compact so that they can be easily carried and used at various occasions.
Here, the optical device incorporated in the projector includes a light modulation element such as a liquid crystal panel, and includes polarizing plates on the incident side and the emission side of the liquid crystal panel. And while these liquid crystal panels and polarizing plates themselves are downsized, their mounting structure is also space-saving.

  For example, in Patent Document 1, three light modulation devices are housed in holding frames, the three polarizing elements are respectively fixed between a pair of fixing plates, and fixed base members are provided on the three light flux incident end surfaces of the cross dichroic prism. Are attached, pin-like members are inserted into holes formed at the four corners of the holding frame and the fixing plate, respectively, and the tip of the pin-like member is bonded and fixed to the base member. Thus, the members are assembled in several layers, and the liquid crystal panel, the polarizing element, and the cross dichroic prism are integrated. Such a configuration eliminates the need for a structure that supports the light modulation device alone, thereby reducing the size.

  In Patent Document 2, a pair of upper and lower pedestals is provided on an end surface intersecting with any light beam incident end surface of the cross dichroic prism, and a holding member is directly fixed to the pedestal. The holding member and the liquid crystal panel are pin-shaped members. It is fixed using a spacer. As a result, a large light transmission region on the light incident end face can be secured, and the optical device and the entire projector can be downsized through downsizing of the cross dichroic prism.

On the other hand, miniaturization is promoted as described above, and the brightness of the light source is enhanced so that a clear projected image can be displayed even in a bright place.
Along with this, the luminous flux from the light source with high brightness is concentrated on the miniaturized liquid crystal panel and polarizing plate, the heat density is increased, and the heat load on the liquid crystal panel and polarizing plate is very high. It is getting bigger. Due to this thermal load, the organic material used for the liquid crystal panel and the polarizing plate may be distorted and deteriorated, or the liquid crystal may be overheated, resulting in malfunction.

Furthermore, since the polarizing plate transmits only the light flux in the direction along the polarization axis among the incident light flux and absorbs the light flux in the other direction, it easily overheats. In addition, since the gradation characteristic of the optical image is obtained by applying a voltage to the liquid crystal panel and changing the transmittance of the exit side polarizing plate according to the applied voltage, in particular, in the exit side polarizing plate, Deterioration due to absorbed heat is more likely to occur, and there is a possibility that the image quality of an optical image may be deteriorated, such as a light leakage phenomenon without being absorbed.
The above-mentioned problems are not limited to the polarizing plate, and may occur in the same manner even when an optical conversion element having other optical functions that easily cause thermal deterioration, such as a viewing angle correction plate or a retardation plate, is employed. There is.

In response to these concerns, in Patent Document 1, a pair of spacers and support members that can secure a sufficient gap between the liquid crystal panel and the light beam incident end surface are provided in parallel to both ends of the holding frame of the liquid crystal panel. . Here, between the liquid crystal panel and the cross dichroic prism, a cooling air flow path is formed in a direction along any light beam incident end face, that is, in the vertical direction. It arrange | positions so that it may extend up and down so that the flow of air may not be interrupted.
In Patent Document 2, a holding member having a convex portion formed on the surface is fixed to the pedestal of the cross dichroic prism, and is formed between the light incident end face and the holding member adjacent to the convex portion. Cooling air is introduced into the gap.

By the way, when an optical device is incorporated in a projector, it is necessary to arrange each liquid crystal panel at a back focus position of the projection lens. In addition, each pixel of the projected image is formed by additive color mixture of the three primary colors of red, green, and blue. Therefore, in order to obtain a finer image, the relative position of each liquid crystal panel is adjusted with high accuracy, and the pixel It is necessary to prevent deviation.
Therefore, in Patent Document 1, the position of each liquid crystal panel with respect to each light beam incident end surface can be adjusted by moving a triangular prism spacer with respect to the inclined surface of the support member fixed to the holding frame of the liquid crystal panel. Yes.
On the other hand, in Patent Document 2, the liquid crystal panel is fixed to the pedestal via the holding member with an adhesive, and the liquid crystal panel is moved by moving the holding member along the outer peripheral surface of the pedestal while the adhesive is uncured. The position can be adjusted. Further, by adjusting the insertion amount of the spacer inserted between the liquid crystal panel and the holding frame of the liquid crystal panel, the liquid crystal panel can be moved along the optical axis direction to adjust the focus.

JP 2002-221758 A (FIG. 6) JP 2003-121931 A

However, when the pin-shaped member or spacer as described above is provided, there is a problem that the pin-shaped member or the spacer becomes bulky when viewed as the entire optical device, and the size cannot be sufficiently reduced.
In particular, when a spacer is used to fix the liquid crystal panel, the position of the spacer overlaps the light beam transmission area of the cross dichroic prism, and the light is blocked by the spacer, so the light beam transmission area is the same size as when no spacer is provided. In order to ensure the above, the size of the cross dichroic prism is increased with respect to the size of the image forming area of the liquid crystal panel, which also hinders the downsizing of the optical device.

On the other hand, when a pin-shaped member is used for fixing the liquid crystal panel, the liquid crystal panel is only partially bonded and supported by the pin-shaped member, so that a plurality of optical conversion elements such as polarizing plates are used to form a pin shape. When a load is applied to the member, when an impact is applied, or when the member is used for many years, the relative position of each liquid crystal panel is likely to be displaced, which may cause pixel displacement in the optical image.
Furthermore, since there are many complicated parts such as pin-shaped members, spacers, base members, fixing plates, support members, holding members, etc., it takes time and labor to assemble these various parts. However, there is a problem that the manufacturing cost including capital investment increases.

  In view of the above problems, the object of the present invention is to further reduce the size, reduce the manufacturing cost, and facilitate the manufacturing by simplifying the structure, and improve the bonding strength between components to improve the image quality. It is another object of the present invention to provide an optical device that can contribute to the improvement of the above-mentioned performance and that can be cooled sufficiently efficiently, and a projector including the optical device.

  The optical device of the present invention includes a plurality of light modulation devices that form an optical image by modulating a plurality of color lights according to image information for each color light, and a plurality of light flux incident end faces that face the light modulation devices. An optical device comprising a color synthesis optical device for synthesizing the optical images formed by the respective light modulation devices, and a pedestal provided on an end surface intersecting with a plurality of light beam incidence end surfaces of the color synthesis optical device, An adjustment member that is inserted between the pedestal and the light modulation device and that positions and adjusts the light modulation device at a predetermined position, and the outer peripheral portion of the pedestal has a light beam incident end surface of the color synthesis optical device. An inclined surface that is inclined is formed, and the adjusting member is inserted along the inclined surface.

Here, a cross dichroic prism or the like can be adopted as the color synthesis optical device. The cross dichroic prism is a hexahedron having a substantially cubic shape in which four right-angle prisms are combined. Color lights emitted from three light modulation devices arranged opposite to the light incident end faces in three directions are applied to the interfaces of the right-angle prisms. It is synthesized by the provided X-shaped dielectric multilayer film.
In addition, when the optical device is incorporated in a housing or the like of an electronic device, the pedestal can be used as a member for fixing to the housing. The shape of this pedestal can be formed into a plate shape or block shape according to the shape / dimensions of the end surface intersecting with the plurality of light beam incident end surfaces of the color synthesizing optical device, for example. It is conceivable to form a fixing part or the like.
Furthermore, as the shape of the adjustment member, any shape that can be fixed along the inclined surface of the pedestal can be adopted. For example, a columnar, plate-like, or rod-like member having a polygonal cross section having an inclined surface that can come into contact with the inclined surface of the pedestal can be suitably employed, and a triangular prism shape can be most suitably employed.

According to this invention, the adjustment member is inserted and fixed between the pedestal and the light modulation device, and the light beam emitted from the light modulation device is not blocked by the adjustment member. As a result, since the light beam incident end face of the color synthesis optical device is effectively used, the color synthesis optical device is not increased in size, and the optical device can be reliably reduced in weight and size.
Further, by adjusting the position and posture of the adjusting member with respect to the inclined surface of the pedestal, each light modulation device can be positioned. This enables high-precision alignment between the light modulation devices, and when the optical device of the present invention is incorporated in an optical apparatus such as a projector, the focus adjustment of the projection lens is performed by adjusting the position of the light modulation device. This can contribute to the improvement of the image quality of the optical image.
Regarding the positioning adjustment, the inclined surface is formed between the light incident end surface and the end surface where the light flux is not incident so that the distance between the light modulating device and the light incident end surface at the position opposite to the light modulating device can be easily adjusted. It is preferable that the directions intersect each other.

  Further, since the adjustment member is inserted and fixed along the inclined surface of the pedestal, the light modulation device has been attached to the inclined surface of the pedestal as compared with the conventional case where the light modulation device is partially bonded and supported and fixed by the pin-shaped member. Accordingly, the bonding area between the pedestal and the adjustment member is sufficiently secured, and the bonding strength between the light modulation device and the color synthesis optical device supported via the adjustment member is improved. As a result, even when an impact is applied, when used for many years, or when a plurality of optical conversion elements such as polarizing plates are arranged between the color synthesizing optical device and the light modulation device and a load is applied to the adjustment member, etc. Since the relative position between the light modulation device and the color synthesizing optical device is not displaced and pixel displacement is prevented, this point can also contribute to the improvement of the image quality.

Then, the adjustment member is inserted and fixed along the inclined surface of the pedestal, and the inclined surface and the adjustment member overlap each other, so that the cooling is performed in a direction along any light beam incident end surface between the light beam incident end surface and the light modulation device. When the fluid flows, the flow is not hindered by the adjustment member. Therefore, a sufficiently large flow path for cooling fluid or the like can be provided between the light beam incident end face and the light modulation device, and a sufficient cooling effect can be achieved.
Furthermore, in the part where the inclined surface of the pedestal and the adjustment member overlap, the outer dimension of the adjustment member is transferred into the dimension of the pedestal, so that downsizing of the optical device is not hindered.

Here, the pedestal is a member for incorporating the optical device into the optical device, and the adjustment member is inserted and fixed between the pedestal and the light modulation device to support the light modulation device on the color synthesis optical device, It is a member for adjusting the position of the light modulation device. By effectively using these pedestals and adjusting members, which are indispensable in the manufacture and use of optical devices, as described above, the light modulation device can be made into a color synthesis optical device without hindering the downsizing of the optical device. Can be securely fixed and attached.
Therefore, compared to the need for a wide variety of fixing plates, holding members, base members, support members, pin-like members, spacers, etc., the number of parts and the manufacturing process and assembly work are simplified by simplifying the structure. And, in turn, the manufacturing cost can be reduced more reliably.

In the optical device according to the aspect of the invention, the pedestal is provided on one end surface that intersects the plurality of light flux incident end surfaces and the other end surface, and the inclined surfaces are substantially parallel to each other on these pedestals. It is preferable.
Here, the end surface on which the pedestal is provided is the upper and lower end surfaces of the color combining optical device when the light beam incident end surface is on three sides of the color combining optical device.

According to the present invention, since the adjustment members are inserted into the inclined surfaces respectively formed on the pair of pedestals, both ends of the light modulation device are supported by the adjustment members, and positioning adjustment of the light modulation device is facilitated.
On the other hand, since the inclined surface is substantially parallel between the pedestals, when adjusting the positioning of the light modulation device, the adjustment member is moved along the inclined surface of the pedestal without shifting the positional relationship between the adjustment member and the light modulation device. It is possible to move, and positioning work is facilitated also in this respect.
Furthermore, even when an adhesive is applied to the contact surface into which the adjustment member is inserted, the portion that is contaminated by the adhesive during positioning adjustment can be reduced.

In the optical device according to the aspect of the invention, it is preferable that the base and the adjustment member are made of a heat conductive material.
According to the present invention, the heat generated in the light modulation device or the like due to the irradiation of the light flux is efficiently conducted to the adjusting member and the pedestal and released to the outside. Further, heat dissipation is promoted not only for the light modulation device but also for the color synthesizing optical device and other members connected to the adjustment member and the pedestal so as to conduct heat. Such an improvement in the heat radiation cooling performance can prevent thermal deterioration of the light modulator and various optical elements.
In addition, as a heat conductive material, aluminum, magnesium, copper, iron, titanium, an alloy containing these, etc. are employable.

The optical device of the present invention includes an optical conversion element disposed between the light beam incident end surface and the light modulation device, and a holding member that holds the optical conversion device, and the light modulation device is attached to the holding member. It is preferable that the adjustment member is fixed and inserted between the holding member and the inclined surface of the pedestal.
Here, as the optical conversion element, a polarizing film, a polarizing plate employing a film for converting optical characteristics such as a polarizing film, a viewing angle widening film, a retardation film, a viewing angle correction plate, a retardation plate, or the like can be used. . For the substrate of these optical conversion elements, sapphire glass, quartz glass, crystal, or the like can be used as a material. Such an optical conversion element may be a single structure or a structure in which a plurality of optical conversion elements are combined, and may be provided not only on the emission side of the light modulation device but also on the incident side.
The holding member is preferably made of a material having good thermal conductivity such as aluminum, magnesium, copper, iron, titanium, an alloy containing these, or a synthetic resin containing a carbon filler.

According to the present invention, the heat generated in the optical conversion element is immediately conducted to the holding member and quickly released from the holding member to the outside. Thereby, the optical conversion element is cooled, and deterioration due to overheating can be prevented.
In addition, since the heat generated in the optical conversion element is quickly released in this way, the amount of heat that easily enters and exits between the light modulation device and the optical conversion element is reduced according to the temperature. Therefore, since it becomes difficult to produce the backflow of heat, it can cool more effectively by means according to each of the light modulation device and the optical conversion element. In this way, it is possible to prevent malfunction due to temperature rise of the light modulation device.
If the holding member is configured so that the optical conversion element can be attached and detached, the optical conversion element can be replaced with a new one even when a manufacturing defect or alteration occurs, and the reworkability can be improved.

In the optical device according to the aspect of the invention, the holding member may include an outer member having a C-shaped cross section to which the light modulation device is fixed, and an inner member having a C-shaped cross section accommodated in the outer member. preferable.
Here, the outer member and the inner member can be easily formed by, for example, press sheet metal processing in which a metal pipe material is cut.

According to the present invention, there are a large number of holding portions for holding the optical conversion element, such as the front and back surfaces of the opening and the ends of the C-shaped openings, by forming openings for transmitting the light flux in the outer member and the inner member. Can be formed. This eliminates the need for a member that holds each optical conversion element, thereby reducing the size of the optical device.
Further, the C-shaped width portion functions as a spacer, and the holding position of the optical conversion element can be set appropriately.
Furthermore, since the cooling fluid is rectified inside the C-shaped member and sufficiently hits the optical conversion element, the cooling is efficiently performed and the surface area of the holding member is increased by combining the outer member and the inner member. After all, the heat dissipation performance can be improved.

In the optical device according to the aspect of the invention, it is preferable that the light modulation device is fixed to the holding member via a heat insulating material.
Here, as the heat insulating material, a sheet-like or plate-like one can be suitably employed.
According to this invention, the light modulation device side and the optical conversion element side are thermally made substantially independent from each other by the heat insulating material, and cooling means are individually provided for the optical elements such as the light modulation device and the optical conversion element. Therefore, effective cooling is possible.
As the cooling means for the optical conversion element, for example, the holding member as described above can be preferably used.
On the other hand, as a cooling means of the light modulation device, for example, it is conceivable to dissipate and cool the heat generated in the light modulation device by providing a heat radiating plate around the light modulation device.

The 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.

Hereinafter, a projector according to an embodiment of the present invention will be described with reference to the drawings.
[1-1. (Main projector configuration)
FIG. 1 is a plan view schematically showing the internal structure of the projector 1. The projector 1 has a substantially rectangular parallelepiped resin outer case 2, an optical unit 4 that optically processes a light beam emitted from the light source device 413 to form an optical image according to image information, and a projector 1 And a power supply unit 3 for supplying the power supplied from the outside to these units 4, 5 and the like.

  The outer case 2 accommodates the units 3 to 5, and is not specifically shown. However, the upper case constituting the upper surface portion, the front surface portion, and the side surface portion of the projector 1, and the bottom surface portion of the projector 1 And a lower case constituting the side surface portion and the back surface portion.

  As shown in FIG. 1, a cutout 2 </ b> A is formed on the front surface of the outer case 2. A part of the optical unit 4 housed in the outer case 2 is exposed to the outside from the notch 2A. In addition, on the front surface of the exterior case 2, exhaust ports 2B and 2C for exhausting air in the projector 1 are formed on both sides of the notch 2A. On the bottom surface of the outer case 2, an air inlet (not shown) for sucking cooling air from the outside is formed in a portion corresponding to an optical device 44 (described later) constituting the optical unit 4.

As shown in FIG. 1, the power supply unit 3 is disposed on the right side in FIG. 1 of the optical unit 4 in the exterior case 2. Although not specifically shown, the power supply unit 3 supplies power supplied via a power cable inserted into the inlet connector to a lamp driving circuit (ballast), a driver board (not shown), and the like. Is.
The lamp driving circuit supplies the supplied power to the light source lamp 411 of the optical unit 4. Although not shown, the driver board is arranged above the optical unit 4 and controls the liquid crystal panels 441R, 441G, and 441B, which will be described later, after performing arithmetic processing on the input image information. is there.

  The power supply unit 3 and the optical unit 4 are covered with a shield plate made of metal such as aluminum or magnesium. The lamp driving circuit and the driver board are also covered with a metal shield plate such as aluminum or magnesium. As a result, leakage of electromagnetic noise from the power supply unit 3 or the driver board to the outside is prevented.

  The cooling unit 5 takes cooling air into the flow path in the projector 1, absorbs heat generated in the projector 1 in the taken cooling air, and discharges the warmed cooling air to the outside. The inside of the projector 1 is cooled. The cooling unit 5 includes an axial flow intake fan 51, a sirocco fan 52, and an axial flow exhaust fan 53.

  The axial flow intake fan 51 is disposed below the optical device 44 of the optical unit 4 and above the intake port of the exterior case 2. The axial-flow intake fan 51 sucks cooling air from the outside into the optical unit 4 through this intake port, and cools the optical device 44.

  The sirocco fan 52 is disposed below the light source device 413 of the optical unit 4. The sirocco fan 52 draws the cooling air in the optical unit 4 sucked by the axial flow intake fan 51, takes heat of the light source device 413 in the drawing process, and passes through a duct 52 </ b> A disposed below the optical unit 4. Then, the cooled cooling air is discharged to the outside from the exhaust port 2B.

  The axial exhaust fan 53 is disposed between the exhaust port 2 </ b> C formed on the front surface of the exterior case 2 and the power supply unit 3. The axial exhaust fan 53 sucks the air in the vicinity of the power supply unit 3 warmed by the power supply unit 3 and discharges it to the outside from the exhaust port 2C.

[1-2. Configuration of optical unit)
FIG. 2 is a plan view schematically showing the optical unit 4.
As shown in FIG. 2, the optical unit 4 is a unit that is formed in a substantially L-shaped plane and optically processes a light beam emitted from the light source lamp 411 to form an optical image corresponding to image information. , An integrator illumination optical system 41, a color separation optical system 42, a relay optical system 43, an optical device 44, and a projection lens 46 as a projection optical system. These optical components 41 to 44, 46 are housed and fixed in an optical component casing 47 as an optical component casing.

  As shown in FIG. 2, the integrator illumination optical system 41 forms images on three liquid crystal panels 441 constituting the optical device 44 (respectively indicated as liquid crystal panels 441R, 441G, and 441B for red, green, and blue color lights). This is an optical system for illuminating the area substantially uniformly, and includes a light source device 413, a first lens array 418, a second lens array 414, a polarization conversion element 415, and a superimposing lens 416.

  The light source device 413 includes a light source lamp 411 that emits a radial light beam, an ellipsoidal mirror 412 that reflects radiation emitted from the light source lamp 411, and light that is emitted from the light source lamp 411 and reflected by the ellipsoidal mirror 412. And a collimating concave lens 413A that converts the light into parallel light. A UV filter (not shown) is provided on the plane portion of the collimating concave lens 413A. As the light source lamp 411, a halogen lamp, a metal halide lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, or the like can be used. Further, a parabolic mirror may be used instead of the ellipsoidal mirror 412 and the collimating concave lens 413A.

  The first lens array 418 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 lamp 411 into a plurality of partial light beams.

  The second lens array 414 has substantially the same configuration as the first lens array 418, and has a configuration in which small lenses are arranged in a matrix. The second lens array 414 has a function of forming an image of each small lens of the first lens array 418 on the liquid crystal panel 441 together with the superimposing lens 416.

  The polarization conversion element 415 is disposed between the second lens array 414 and the superimposing lens 416 and is unitized with the second lens array 414. Such a polarization conversion element 415 converts the light from the second lens array 414 into a single type of polarized light, thereby improving the light use efficiency in the optical device 44. Further, as indicated by a two-dot chain line 410 in FIG. 2, the unitized polarization conversion element 415, the second lens array 414, and the first lens array 418 are integrally unitized.

  Specifically, each partial light converted into one kind of polarized light by the polarization conversion element 415 is finally substantially superimposed on the liquid crystal panels 441R, 441G, 441B of the optical device 44 by the superimposing lens 416. In the projector 1 (optical device 44) using the liquid crystal panel 441 of the type that modulates polarized light, only one type of polarized light can be used, and therefore almost half of the light from the light source lamp 411 that emits randomly polarized light is not used. . Therefore, by using the polarization conversion element 415, the light emitted from the light source lamp 411 is converted into one type of polarized light, and the light use efficiency in the optical device 44 is enhanced. Such a polarization conversion element 415 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 reflection mirrors 423 and 424, and a plurality of partial light beams emitted from the integrator illumination optical system 41 by the dichroic mirrors 421 and 422 are red, green, It has a function of separating into three color lights of blue.
The relay optical system 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 (red light) separated by the color separation optical system 42 to the liquid crystal panel 441R.

  In such optical systems 41, 42, and 43, the dichroic mirror 421 of the color separation optical system 42 transmits the blue light component of the light beam emitted from the integrator illumination optical system 41, and the red light component and the green light component. Is reflected. The blue light component transmitted by the dichroic mirror 421 is reflected by the reflection mirror 423, passes through the field lens 417, and reaches the blue liquid crystal panel 441B. The field lens 417 converts each partial light beam emitted from the second lens array 414 into a light beam parallel to the central axis (principal ray). The same applies to the field lens 417 provided on the light incident side of the other liquid crystal panels 441R and 441G.

  Of the red light and green light reflected by the dichroic mirror 421, the green light is reflected by the dichroic mirror 422 and passes through the field lens 417 to reach the green liquid crystal panel 441G. On the other hand, the red light passes through the dichroic mirror 422, passes through the relay optical system 43, passes through the field lens 417, and reaches the liquid crystal panel 441R for red light. The relay optical system 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 divergence or the like. Because. That is, the partial light beam incident on the incident side lens 431 is transferred to the field lens 417 as it is. The relay optical system 43 is configured to pass red light out of the three color lights, but may be configured to pass other color light such as blue light.

  The optical device 44 modulates an incident light beam according to image information to form a color image. The light beam emitted from the color separation optical system 42 is incident, and an incident side polarizing plate 444 serving as a so-called polarizer. And three light modulation devices 440R, 440G, and 440B arranged in the latter stage of the optical path of each incident-side polarizing plate 444, and a viewing angle correction plate 640 arranged in the latter stage of the optical path of each of the light modulation devices 440R, 440G, and 440B (FIG. 5), an exit-side polarizing plate 630 serving as a so-called analyzer, and a cross dichroic prism 443 serving as a color synthesizing optical device. The optical components 441, 443, 620 are integrally formed to constitute the optical device body 48.

  The incident-side polarizing plate 444 is an optical conversion element configured as a separate body from the optical device main body 48. The incident-side polarizing plate 444 transmits only polarized light in a certain direction among the light beams separated by the color separation optical system 42 and absorbs the light beams in other directions, and is polarized on a substrate such as sapphire glass. A film is attached.

The optical components 41 to 44 described above are accommodated in an optical component casing 47 made of synthetic resin as an optical component casing.
Although not shown in the figure, the optical component casing 47 is provided with grooves for fitting the above-described optical components 414 to 418, 421 to 423, 431 to 434, and 444 (FIG. 2) slidably from above. A component storage member and a lid-like member that closes the upper opening side of the component storage member are provided. A light source device 413 is accommodated on one end side of the substantially L-shaped optical component casing 47 and a projection lens 46 is fixed on the other end side via a head portion 49.

[1-3. Configuration of optical device main body constituting optical device]
3 to 5 show the optical device main body 48 constituting the optical device 44. FIG. 3 is a view of the optical device main body 48 as viewed from below, and FIG. 4 is a side view thereof.
The optical device main body 48 includes a cross dichroic prism 443, bases 446 and 447 fixed to upper and lower surfaces which are end surfaces substantially orthogonal to the light beam incident end surface of the cross dichroic prism 443, and adjustments fixed to the bases 446 and 447. Six adjustment members 700 as members, three holder units 600 as holding members fixed to the bases 446 and 447 via the adjustment members 700, and light modulation devices 440R and 440G fixed to the holder units 600 , 440B.

  The cross dichroic prism 443 forms a color image by synthesizing the images emitted from the light modulation devices 440R, 440G, and 440B and modulated for each color light, and has a substantially cubic hexahedron appearance. In the cross dichroic prism 443, a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in an approximately X shape along the interfaces of four right-angle prisms. Three color lights are synthesized by the multilayer film. The color image synthesized by the cross dichroic prism 443 is emitted from the projection lens 46 and enlarged and projected on the screen.

The pedestal 445 is a member that supports and fixes the cross dichroic prism 443 and is joined to the holder unit 600 via the adjustment member 700. The pedestal 445 is fixed to the upper surface of the cross dichroic prism 443, and the cross dichroic prism 443. And a lower pedestal 447 that is fixed to the lower surface.
The upper base 446 is fixed with an ultraviolet curable adhesive after the angle adjustment of the cross dichroic prism 443 is completed. The lower pedestal 447 is fixed to the cross dichroic prism 443 with a silicone-based heat conductive adhesive.

The upper pedestal 446 and the lower pedestal 447 are both made of aluminum, magnesium, copper, iron, titanium, or the like, or an alloy containing these, and are substantially larger in outer dimensions than the upper and lower surfaces of the cross dichroic prism 443. It is formed in a rectangular plate shape.
In the outer peripheral portion of the upper pedestal 446, an inclined surface 446A is formed at an intermediate portion on three side surfaces. The inclined surface 446A is formed in a direction that intersects both the light beam incident end surface of the cross dichroic prism 443 and the end surface on which no light beam is incident.
Specifically, the upper pedestal 446 is formed so as to be gradually inclined inward by approximately 45 ° from the upper end toward the lower end.
The upper pedestal 446 is formed with arm portions 448 extending outward from the four corners, and the optical device main body 48 is bonded and fixed to the optical component casing 47 by the arm portions 448.

Also in the outer peripheral portion of the lower pedestal 447, an inclined surface 447A is formed at an intermediate portion on three side surfaces in substantially the same manner as the upper pedestal 446. When the upper pedestal 446 and the lower pedestal 447 are fixed to the cross dichroic prism 443, the inclined surface 446A and the inclined surface 447A are formed to be substantially parallel to each other.
The lower pedestal 447 is formed with a concave portion 447B (FIG. 4) hollowed out in a substantially circular shape, which increases the contact area with the cooling air and facilitates heat dissipation.

  The light modulation devices 440R, 440G, and 440B include liquid crystal panels 441R, 441G, and 441B serving as light modulation elements, and a panel holding frame 820 (FIG. 6) that holds the liquid crystal panels 441R, 441G, and 441B, respectively, and has a substantially rectangular shape as a whole. It is formed in a plate shape.

Although not specifically shown, the liquid crystal panels 441R, 441G, and 441B include a glass driving substrate and a counter substrate, and a TN (twisted nematic) type liquid crystal injected between these substrates, and the incident side. A light beam incident through the polarizing plate 444 is modulated according to image information and emitted.
Inside the drive substrate are formed pixel electrodes made of a transparent conductor such as ITO (Indium Tin Oxide), switching elements such as TFT elements corresponding to each pixel electrode, wiring, alignment film for arranging liquid crystal molecules, and the like. Yes. Further, on the inner surface of the counter substrate, a counter electrode corresponding to the pixel electrode, an alignment film whose direction is substantially orthogonal to the alignment film of the driving substrate, and the like are formed. Thereby, an active matrix type liquid crystal panel is formed.
Note that a control cable 442 extends from between the drive substrate and the counter substrate.

The panel holding frame 820 is a rectangular frame member in which a rectangular opening 821 corresponding to the image forming area of the liquid crystal panels 441R, 441G, and 441B is formed, and contains magnesium, aluminum, titanium, or the like. It is made of a material having good thermal conductivity, such as a resin material containing an alloy or a carbon filler.
At the four corners of the panel holding frame 820, through holes 830 penetrating the panel holding frame 820 are formed. Further, heat radiation fins 822 are formed on the upper surface, and heat conducted from the liquid crystal panels 441R, 441G, 441B is easily radiated through the panel holding frame 820 by the heat radiation fins 822.

FIG. 5 is an exploded perspective view of the holder unit 600.
As shown in FIG. 5, the holder unit 600 is configured by two channel-shaped members having a C-shaped cross section, an outer holder 610 as an outer member and an inner holder 620 as an inner member. The outer holder 610 and the inner holder 620 are formed by sheet metal pressing by opening a metal pipe made of aluminum, magnesium, titanium, or the like, and are combined in a nesting manner so as to face each other. 630 and optical conversion elements such as a viewing angle correction plate 640 are held.

As shown in FIG. 4, the outer holder 610 stands up toward the out-of-plane direction (optical axis direction) from the main body 611 fixed to the light beam incident end face of the cross dichroic prism 443 and the left and right ends of the main body 611. And a pair of upstanding pieces 612. In the main body 611, a substantially rectangular opening 615 for transmitting a light beam is formed at a substantially center. In addition, the front end sides of the standing pieces 612 are bent in a direction approaching each other, and are bent pieces 613 substantially parallel to the plate surface of the main body 611.
The inner holder 620 is also formed to include a main body 621, an upright piece 622, an opening 625, and a bent piece 623, similar to the outer holder 610.

Here, the exit-side polarizing plate 630 is configured in substantially the same manner as the incident-side polarizing plate 444, and transmits only polarized light in a predetermined direction among the light beams emitted from the liquid crystal panels 441R, 441G, and 441B, and transmits the other light beams. Absorb.
By the way, since the transmittance of the exit side polarizing plate 630 is changed according to the voltage applied to the liquid crystal panels 441R, 441G, and 441B, the gradation characteristic of the color of the optical image is realized. Is more susceptible to deterioration by light absorption heat than the incident side polarizing plate 444.
In the present embodiment, the polarization axis of the light beam transmitted through the exit side polarizing plate 630 is set to be orthogonal to the polarization axis of the incident side polarizing plate 444 (the alignment films of the liquid crystal panels 441R, 441G, 441B). Corresponds to the array direction). That is, when no voltage is applied to the liquid crystal panels 441R, 441G, and 441B, the liquid crystal molecules are twisted by approximately 90 ° along the polarization axis of the exit side polarizing plate 630 from the polarization axis of the incident side polarizing plate 444, and along the liquid crystal molecules. The luminous flux is transmitted and an all-white image is formed. On the other hand, when an all-black image is formed by applying a voltage, the exit-side polarizing plate 630 needs to absorb all the unnecessary light emitted from the liquid crystal panels 441R, 441G, and 441B, and the heat load is increased. Become bigger.

Such an exit-side polarizing plate 630 is composed of a pair of polarizing plates 631 and 632 whose polarization axes coincide with each other. Even when the first polarizing plate 632 cannot sufficiently absorb unnecessary light, The first polarizing plate 631 can reliably convert the light into constant polarized light.
Although these polarizing plates 631 and 632 are not specifically illustrated, a polarizing film as an optical conversion film in which a polyvinyl alcohol (PVA) film and an acetate cellulose-based rectangular film are laminated, and the polarizing film And a sapphire glass substrate to which is attached.

  The viewing angle correction plate 640 is formed 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. By disposing 640, the viewing angle of the projected image is enlarged, and the contrast of the projected image is greatly improved. The viewing angle correction plate 640 is also heated by light irradiation.

As shown in FIG. 5, the polarizing plates 631 and 632 and the viewing angle correction plate 640 are respectively disposed around the openings 615 and 625 of the outer holder 610 and the inner holder 620 by a double-sided tape, a heat conductive adhesive, or the like. Retained.
Specifically, around the opening 625 of the inner holder 620, a viewing angle correction plate 640 is held on the outer surface side, and a polarizing plate 632 is held on the inner surface side. A polarizing plate 631 is held around the opening 615 of the outer holder 610 on the inner surface side.
As described above, since the optical conversion elements such as the polarizing plates 631 and 632 and the viewing angle correction plate 640 can be held on both the front and back surfaces of the openings 615 and 625 of the outer holder 610 and the inner holder 620, a plurality of optical conversion elements are provided. Even in cases, there is no problem with the holding position, so there is no need for a place. In addition, when the outer holder 610 and the inner holder 620 are combined, a polarizing plate or the like can be held in a gap generated between the outer holder 610 and the inner holder 620. The polarizing plates 631 and 632 and the viewing angle correction plate 640 can be replaced with new ones for the outer holder 610 or the inner holder 620 even when manufacturing defects or alterations occur in any of them, and the reworkability is high. Yes.
Note that another type of optical conversion element such as a retardation plate can be set in the outer holder 610 and the inner holder 620. Further, the fixed position of these optical conversion elements can be adjusted according to the color of incident light and various conditions.

The inner holder 620 is accommodated inside the outer holder 610 so that the main body portions 611 and 621 face each other, and the projections and recesses 612A and 622A formed on the standing pieces 612 and 622 are engaged with each other. The outer holder 610 and the inner holder 620 are combined, and the viewing angle correction plate 640, the polarizing plate 632, and the polarizing plate 631 are arranged in this order from the light beam incident side. Further, the polarization axes of the polarizing plates 631 and 632 in the outer holder 610 and the inner holder 620 coincide with each other.
Thus, the outer holder 610 and the inner holder 620 are nested, and the surface area of the holder unit 600 of the upright pieces 612 and 622 and the bent pieces 613 and 623 is increased, and the main body portions 611 and 621 and the upright pieces 612 are increased. , 622 and the bent pieces 613, 623 cover the polarizing plates 631, 632, so that the thermal conductivity between the polarizing plates 631, 632 and the outer holder 610 and the inner holder 620 can be improved.

3 and 4, the adjustment member 700 is a substantially triangular prism-like member inserted between the inclined surface 446A and the upper end of the outer holder 610 and between the inclined surface 447A and the lower end of the outer holder 610, respectively. Therefore, it is made of a material having good thermal conductivity such as aluminum, magnesium, titanium, or an alloy containing these.
The cross-sectional shape of the adjusting member 700 is a substantially right isosceles triangle. In the hypotenuse 710 that is the hypotenuse opposite to the right angle, the adjustment member 700 is provided on any one of the inclined surfaces 446A and 447A of the upper plinth 446 and the lower plinth 447. The support portion 720 that is fixed along the side and that faces the holder unit 600 is fixed to the end portion of the outer holder 610.
In addition, a chuck hole 721 is formed in the support portion 720 that is the two sides other than the oblique side portion 710 and the remaining one side.
A total of six adjustment members 700 are used in the entire optical device main body 48, one on each of the three outer peripheral surfaces of the upper pedestal 446 and the lower pedestal 447.

The optical device main body 48 is assembled as follows.
First, polarizing plates 631 and 632 and a viewing angle correction plate 640 are accommodated in advance in the above-described outer holder 610 and inner holder 620, and the outer holder 610 and inner holder 620 are combined and integrated as a holder unit 600. .
Further, the light modulation devices 440R, 440G, and 440B are assembled to the holder unit 600 together with the panel holding frame 820. This assembly is performed by inserting four screws 811 into the through holes 830 of the panel holding frame 820 and screwing the tip end portions of the screws 811 into the holes formed in the bent pieces 613 of the outer holder 610. Under the present circumstances, between the panel holding frame 820 and the bending piece 613 of the outer side holder 610, the metal heat sink 910 and the heat insulation sheet 920 (refer FIG. 4 and abbreviate | omitted in FIG. 3) as a heat insulating material are interposed. .

Here, the heat radiating plate 910 is in contact with the panel holding frame 820, and releases heat generated in the liquid crystal panels 441R, 441G, and 441B. The heat insulating sheet 920 is attached to the outer holder 610 side with respect to the heat radiating plate 910 and insulates between the light modulation devices 440R, 440G, and 440B and the holder unit 600. These heat radiating plate 910 and heat insulating sheet 920 may be provided as necessary, and either or both of them may not be provided.
Further, the screw 811 is made of transparent acrylic that transmits ultraviolet rays and has heat insulation properties. The cost is reduced by adopting a commercially available metric screw (for example, a screw diameter of M1.7, a length of 6 mm). Yes. Furthermore, metal screws other than acrylic screws can be used as long as they can be irradiated with ultraviolet rays from the outside of the fixed portion.

  When the above preparatory work is completed, the components of the optical device main body 48 are positioned and assembled with high accuracy. In this assembly, by using a thermosetting adhesive, an ultraviolet curable adhesive, or the like according to the material of the member to be bonded, the adhesive can be quickly cured to improve work efficiency. That is, a thermosetting adhesive can be suitably used for a material having high thermal conductivity such as a metal, while a light-transmitting material such as a transparent synthetic resin is used so that light can enter the bonded portion. In this case, an ultraviolet curable adhesive or the like can be suitably used.

In assembling the optical device main body 48, first, the upper pedestal 446 and the lower pedestal 447 are appropriately bonded and fixed to the upper and lower end surfaces of the cross dichroic prism 443, respectively.
Next, the panel holding frame 820 of the light modulation device 440 </ b> G that directly faces the projection lens 46 is attracted by the jig together with the holder unit 600, and is disposed opposite to the light beam incident end face of the cross dichroic prism 443.
Further, while the adjustment member 700 is chucked in the hole 721, the adjustment member 700 whose outer peripheral surface is coated with a thermosetting adhesive or an ultraviolet curable adhesive is attached to the inclined surface 446 A of the upper base 446 and the upper end of the main body 611. And between the inclined surface 447A of the lower pedestal 447 and the lower end of the main body 611, respectively.

Then, the light modulation device 440G is moved while being sucked together with the holder unit 600 by a jig, and focus adjustment is performed so that the focus surface of the liquid crystal panel 441G is aligned with the back focus surface of the projection lens 46.
At this time, the light modulation device 440G arbitrarily moves along the in-plane direction of the inclined surfaces 446A and 447A. When the light modulation device 440G moves, the adjustment member 700 follows the light modulation device 440G via the holder unit 600 by the surface tension of the adhesive applied to the outer periphery and changes the position and posture, so that the workability is excellent. .
In addition, since the inclined surfaces 446A and 447A are substantially parallel to each other, the adjusting member 700 can be moved along the inclined surfaces 446A and 447A without shifting the positional relationship between the adjusting member 700 and the light modulation device 440G. Excellent in properties and can reduce the number of parts that are stained with adhesive

When the position of the light modulation device 440G is adjusted, hot air, a hot beam, or the like is introduced near the adjustment member 700 to cure the thermosetting adhesive, and the light modulation device 440G is fixed.
At this time, since the adjustment member 700, the outer holder 610, the upper pedestal 446, and the lower pedestal 447 are all made of metal having good heat conduction efficiency, the adhesive can be quickly cured by heat conduction.
In addition, when the same metal material is used for the adjustment member 700, the outer holder 610, the upper pedestal 446, and the lower pedestal 447, the linear thermal expansion coefficient is approximated between the materials, and thus the adhesive due to thermal expansion. Is prevented from peeling.

When the light modulation device 440G is fixed in this manner, the light modulation devices 440R and 440B are similarly attracted, and the focus adjustment as described above is performed, and the liquid crystal panels 441R, 441G, and 441B are connected to each other with the liquid crystal panel 441G as a reference. The alignment adjustment is performed so that the position is harmonized and no color shift occurs in each pixel.
Here, by moving the light modulation devices 440R and 440B along the in-plane directions of the inclined surfaces 446A and 447A, the positions of the light modulation devices 440R and 440B are in the Z direction along the optical axis, and the cross dichroic prism 443 is positioned. Adjustment is possible in any of the X direction, the Y direction, and the rotation directions of the X direction and the Y direction, which are in-plane directions of the light beam incident end face, and the image quality of the optical image can be further refined.

During the focus / alignment adjustment process, the adhesive applied to the outer periphery of the adjustment member 700 is filled between the oblique side portion 710 and the inclined surfaces 446A and 447A, and between the support portion 720 and the surface of the outer holder 610. Is also filled.
As described above, the light modulation devices 440R, 440G, and 440B are fixed to the holder unit 600 in advance, and fixing to the holder unit 600 affects the focus / alignment adjustment of the light modulation devices 440R, 440G, and 440B. Since it does not give, work efficiency is not impaired.

In summary, the oblique side portion 710 and the support portion 720 of the adjustment member 700 are bonded and fixed to the inclined surfaces 446A, 447A and the outer holder 610, so that the light modulation devices 440R, 440G, 440B are the holder unit 600, the adjustment member 700, Further, it is fixed to the cross dichroic prism 443 through the upper pedestal 446 and the lower pedestal 447 in accordance with the overlapping portion of the oblique side portion 710 and the inclined surfaces 446A and 447A.
In this way, the configuration in which the light modulation devices 440R, 440G, and 404B are integrated with the cross dichroic prism 443 eliminates the need for a structure that supports the light modulation devices 440R, 440G, and 440B alone, thereby reducing the size. It is no longer necessary to individually adjust the positions of the light modulation devices 440R, 440G, and 440B and the cross dichroic prism 443 and fix them in the optical component casing 47, greatly reducing the labor of position adjustment and improving assembly. Figured.

Further, the upper base 446 for incorporating the optical device main body 48 into the optical component casing 47 and the light modulation devices 440R, 440G, and 440B are supported, and the positions of the light modulation devices 440R, 440G, and 440B are adjusted. The adjustment member 700 is effectively used as described above, and the light modulation devices 440R, 440G, and 440B can be reliably fixed to the cross dichroic prism 443 without hindering the downsizing of the optical device 44.
Therefore, conventionally, a wide variety of fixing plates, holding members, pin-like members, spacers, and the like are required, and manufacturing by reducing the number of parts and simplifying the structure is included compared to the relatively complicated structure. Simplification of the process, facilitation of manufacture, improvement of shape accuracy, and consequently reduction of manufacturing cost can be realized more reliably.

  Here, the adjustment member 700 overlaps with the inclined surfaces 446A and 447A formed on the upper pedestal 446 and the lower pedestal 447, and in this overlapping portion, the outer dimensions of the adjustment member 700 are the upper pedestal 446 and the lower pedestal 447. Therefore, the size of the optical device 44 is not hindered by the size of the adjustment member 700 itself.

Conventionally, the light modulation devices 440R, 440G, and 440B are partially supported by the pin-like member, and the bonding strength is weak. On the other hand, the adjustment member 700 is sufficient for the upper base 446 and the lower base 447. The light modulation devices 440R, 440G, and 440B can be reliably supported by the cross dichroic prism 443.
Therefore, it can withstand the loads of the polarizing plates 631 and 632, the viewing angle correction plate 640, the outer holder 610, the inner holder 620, and the light modulators 440R, 440G, and 440B, and the impact resistance of the projector 1 is improved. .

A light beam enters the optical device main body 48 described above via the incident-side polarizing plate 444, and the incident light passes through the liquid crystal panels 441R, 441G, and 441B, and further, the viewing angle correction plate 640 and the emission side. The light passes through the polarizing plates 631 and 632 of the polarizing plate 630 and enters the end face of the cross dichroic prism 443.
Here, since the adjustment member 700 is fixed to the upper pedestal 446 and the lower pedestal 447, the light flux that has passed through the liquid crystal panels 441 R, 441 G, 441 B and the like is not blocked by the adjustment member 700. As a result, the light incident end face of the cross dichroic prism 443 is effectively used, so that the cross dichroic prism 443 is not increased in size, and the optical device 44 can be reliably reduced in weight and size.
In addition, due to the miniaturization of the cross dichroic prism, the back focus of the projection lens 46 is shortened, and a lot of light is swallowed by the projection lens 46, so that a bright projection image can be obtained.

On the other hand, the liquid crystal panels 441R, 441G, and 441B, the viewing angle correction plate 640, the polarizing plates 631 and 632, and the cross dichroic prism 443 are heated by the incidence of light. Looking at the heat, the heat generated in the liquid crystal panels 441R, 4441G, and 441B is immediately conducted to the panel holding frame 820 and the heat radiating plate 910, and from the surface of the panel holding frame 820 and the heat radiating plate 910 and the heat radiating fins 822. The heat is quickly released into the cooling air.
Regarding the heat generated in the polarizing plates 631 and 632 and the viewing angle correction plate 640, the adjustment member 700, the holder unit 600, the upper pedestal 446, and the lower pedestal 447 are all made of metal having a good heat conduction efficiency. Therefore, first, it is conducted to the holder unit 600, is conducted to the upper pedestal 446 and the lower pedestal 447 via the adjustment member 700, and is conducted from the arm portion 448 of the upper pedestal 446 to the optical component casing 47, Finally, it is also conducted to the outer case 2 through the optical component casing 47. Therefore, heat generated by the polarizing plates 631 and 632 and the viewing angle correction plate 640 escapes to the heat sinks such as the holder unit 600, the upper pedestal 446, the lower pedestal 447, and the optical component casing 47, thereby increasing the heat capacity. In addition, the contact area with the cooling air increases, and heat exchange with the cooling air becomes efficient.
The heat generated by the cross dichroic prism 443 is conducted to the upper pedestal 446, the lower pedestal 447, and the optical component casing 47 to be dissipated.

Thus, since the heat generated by the liquid crystal panels 441R, 441G, 441B, the polarizing plates 631, 632, the viewing angle correction plate 640, and the cross dichroic prism 443 is dissipated, the liquid crystal panels 441R, 441G, 441B, The amount of heat that enters and exits between the polarizing plates 631 and 632 and the cross dichroic prism 443 decreases.
In addition, the screw 811 that fixes the panel holding frame 820 and the outer holder 610 is a heat insulating material, and the heat insulating sheet 920 is interposed between the panel holding frame 820 and the outer holder 610. Without conducting heat, the light modulation devices 440R, 440G, and 440B side and the holder unit 600 and the cross dichroic prism 443 side are in a thermally independent state. That is, it is possible to prevent thermal backflow between the light modulation devices 440R, 440G, and 440B and the exit-side polarizing plate 630, the viewing angle correction plate 640, and the cross dichroic prism 443, and the liquid crystal panels 441R, 441G, and 441B The heat radiation efficiency of the heat generated by the plates 631, 632, the viewing angle correction plate 640, and the cross dichroic prism 443 can be improved.

Accordingly, the light modulators 440R, 440G, and 440B, the exit side polarizing plate 630, and the viewing angle correction plate 640 can be radiated and cooled sufficiently effectively, so that the polarizing films of the polarizing plates 631 and 632 and the optical angle of the viewing angle correction plate 640 can be obtained. The durability of the conversion film and the liquid crystal panels 441R, 441G, and 441B can be improved and the life of the liquid crystal panels 441R, 441G, and 441B can be improved, and the functional reliability can be improved by preventing deterioration in image quality due to thermal degradation.
Moreover, in the polarizing plates 631 and 632 that are easily overheated by the heat of absorption of light, the cooling effect can be emphasized.

[1-4. (Cooling structure)
Hereinafter, the structure of the air-cooling type cooling mechanism provided in the projector 1 will be described. As shown in FIG. 1, the projector 1 includes an optical device cooling system A that mainly cools the optical device 44 (FIG. 2), a light source cooling system B that mainly cools the light source device 413, and a power supply unit 3. A power supply cooling system C for cooling.
The optical device cooling system A includes an intake port (not shown) formed on the lower surface of the exterior case 2, an axial flow intake fan 51 disposed above the intake port, and an axial flow intake at the bottom surface of the optical component housing 47. And an opening 4 </ b> B formed above the fan 51.

  Fresh cooling air outside the projector 1 is sucked from the intake port of the outer case 2 by the axial flow intake fan 51 and enters the optical component casing 47 through the opening 4B. At this time, although not shown, a rectifying plate is provided on the lower surface of the optical component casing 47 so that the cooling air outside the optical component casing 47 flows from the bottom to the top. Has been rectified.

  As indicated by the arrows in FIG. 1, the cooling air guided into the optical component casing 47 is rectified, and from the bottom to the top of the optical device 44, in other words, any light flux of the cross dichroic prism 443. While flowing in the direction along the incident end face, passing through the front and back sides of the liquid crystal panel 441G, cooling the bases 446, 447, the holder unit 600, the light modulation devices 440R, 440G, 440B, and the incident side polarizing plate 444, It flows upward of the optical device body 48.

At this time, the outer holder 610 and the inner holder 620 have a C-shaped cross section, and the cooling air is rectified inside the main body portions 611 and 621, the standing pieces 612 and 622, and the bent pieces 613 and 623. Since the cooling air flows along the plate surface 632 and the viewing angle correction plate 640, temperature unevenness does not occur in the polarizing plates 631 and 632 and the viewing angle correction plate 640, and the cooling effect is further enhanced.
It should be noted that the cooling air also flows in the gap formed between the light beam incident end surface of the cross dichroic prism 443 and the main body 611 of the outer holder 610 according to the position and posture of the adjustment member 700 on the inclined surfaces 446A and 447A. Even when there is no gap, the polarizing plates 631 and 632 and the viewing angle correction plate 640 are sufficiently effectively cooled by introducing the cooling air into the holder unit 600 as described above.
Here, the adjusting member 700 is fixed along the inclined surfaces 446A and 447A of the upper pedestal 446 and the lower pedestal 447, and the inclined surfaces 446A and 447A and the adjusting member 700 overlap each other, so that the light flux incident end surface of the cross dichroic prism 443 and The adjustment member 700 does not hinder the flow of cooling air between the light modulation devices 440R, 440G, and 440B.
On the other hand, the panel holding frame 820 and the holder unit 600 are spaced apart from each other via screws 811. Cooling air flows into the separated portions vigorously and is supplied to the entire liquid crystal panels 441R, 441G, and 441B.

  As described above, the light modulation devices 440R, 440G, and 440B, the viewing angle correction plate 640, and the emission side polarizing plate 630 are efficiently cooled by the two systems of the cooling mechanism by introducing the cooling air and the above-described heat radiation cooling mechanism. Therefore, even if the air volume of the cooling air circulating inside the projector 1 is not increased, high brightness, downsizing, and low noise of the projector 1 incorporating the optical device 44 are not hindered.

  In addition, in the optical device cooling system A, the circulating cooling air has a function of blowing off dust attached to the surfaces of the liquid crystal panels 441R, 441G, and 441B in addition to the function of cooling the optical device 44. For this reason, the surfaces of the liquid crystal panels 441R, 441G, and 441B are always clean, and stable image quality can be ensured.

  As shown in FIG. 1, the light source cooling system B includes a sirocco fan 52, a duct 52A, and an exhaust port 2B. In this light source cooling system B, the cooling air that has passed through the optical device cooling system A is sucked by the sirocco fan 52, enters the light source device 413, cools the light source lamp 411, and then exits from the optical component casing 47. It passes through the duct 52A and is discharged from the exhaust port 2B to the outside.

  The power supply cooling system C includes an axial exhaust fan 53 provided in the vicinity of the power supply unit 3 and an exhaust port 2C. In the power supply cooling system C, the air heated by the heat from the power supply unit 3 is sucked by the axial exhaust fan 53 and discharged from the exhaust port 2C. At this time, the air in the entire projector 1 is also discharged at the same time, so that heat is not accumulated in the projector 1.

The present invention is not limited to the above-described embodiments, and includes modifications as described below.
The shape, position, number, size, material, and the like of the pedestal, the adjustment member, and the holding member are not limited to those of the above embodiment.

The light modulation device only needs to be fixed to the color synthesizing optical device via the adjustment member and the pedestal, and the object of the present invention can be achieved without the holding member or the like.
The inclined surface of the pedestal is not limited to the inclination angle as in the above embodiment, and the adjustment member can be formed in a shape corresponding to the inclined surface. The adjustment member does not necessarily have a slope corresponding to the slope. Further, even if the adjustment member is formed with a slope and the pedestal is not provided with a slope, the same effect as the present invention is obtained.
The inclined surface and the adjustment member can be fixed so as to overlap entirely or partially.
About the base, the lower part may be fixed to the housing of the projector.

  In addition to the front type projector 1 that performs projection from the direction of observing the screen as in the above-described embodiments, the optical apparatus of the present invention includes a rear type projector that performs projection from the back side of the viewing direction of the screen. It can also be applied to.

  The optical device according to the present invention can be used for a projector as well as other optical devices.

FIG. 2 is a plan view schematically showing the internal structure of the projector according to the embodiment of the invention. The figure which shows the optical unit in the said embodiment typically. The perspective view which shows the optical apparatus main body in the said embodiment from the downward direction. The side view which shows the optical apparatus main body in the said embodiment. The perspective view which shows the holder unit in the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Projector, 44 ... Optical apparatus, 48, 98 ... Optical apparatus main body, 413 ... Light source apparatus (light source), 440R, 440G, 440B ... Light modulation apparatus, 441R, 441G, 441B ... Liquid crystal panel (light modulation element), 443 ... cross dichroic prism (color combining optical device), 445 ... pedestal, 446 ... upper pedestal, 447 ... lower pedestal, 446A, 447A ... inclined surface, 600 ... holder unit (holding member), 610 ... outer holder (outer member) 620 ... Inner holder (inner member), 630 ... Emission side polarizing plate (optical conversion element), 631, 632 ... Polarizing plate, 640 ... Viewing angle correction plate (optical conversion element), 700 ... Adjustment member, 920 ... Thermal insulation sheet (Insulation).

Claims (7)

A plurality of light modulators that modulate a plurality of color lights according to image information for each color light to form an optical image, and a plurality of light beam incident end faces that face each light modulator, and are formed by each light modulator. An optical device comprising a color synthesizing optical device for synthesizing the obtained optical image,
A pedestal provided on an end surface intersecting with a plurality of light beam incident end surfaces of the color synthesis optical device, and an adjustment member inserted between the pedestal and the light modulation device to position and adjust the light modulation device at a predetermined position. Prepared,
An inclined surface that is inclined with respect to a light beam incident end surface of the color combining optical device is formed on an outer peripheral portion of the pedestal,
The optical device is characterized in that the adjustment member is inserted along the inclined surface. The optical device according to claim 1.
The pedestal is provided on one end surface intersecting the plurality of light flux incident end surfaces and the other end surface, respectively.
The inclined surfaces are oriented substantially parallel to each other on these pedestals. The optical device according to claim 1 or 2,
The pedestal and the adjustment member are made of a heat conductive material. The optical device according to any one of claims 1 to 3,
An optical conversion element disposed between the light beam incident end face and the light modulation device;
A holding member for holding the optical conversion element,
The light modulation device is fixed to the holding member,
The optical device, wherein the adjustment member is inserted between the holding member and the inclined surface of the pedestal. The optical device according to claim 4.
The holding device includes an outer member having a C-shaped cross section to which the light modulation device is fixed, and an inner member having a C-shaped cross section accommodated in the outer member. The optical device according to claim 4 or 5,
The optical device, wherein the light modulator is fixed to the holding member via a heat insulating material. 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 1.

Images