JP2005208410A - Optical device and projector - Google Patents

Abstract

An optical device that is low-cost and easy to manufacture and that can cool a light modulation device sufficiently efficiently, and a projector including the optical device.
An optical device comprising a light modulation device 440R, 440G, 440B and a color synthesis optical device 443 includes light modulation elements 441R, 441G, 441B that perform light modulation in the light modulation devices 440R, 440G, 440B. The holding frame 820 to be accommodated is provided with a heat radiating plate 700 made of a heat conductive material that is connected to be capable of heat conduction and releases heat generated in the light modulation devices 440R, 440G, and 440B to the outside. A projection 711A that protrudes in the out-of-plane direction toward the light beam incident end surface of the color synthesis optical device 443 is provided, and the light modulation devices 440R, 440G, and 440B are fixed to the color synthesis optical device 443 through the projection 711A.
[Selection] Figure 4

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 synthesis optical device that synthesizes an optical image formed by a modulation device.

Conventionally, projectors have been used for presentations at conferences, academic conferences, exhibitions, etc., 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. Three optical modulators (liquid crystal panels) that modulate in response, an optical device that has a cross dichroic prism that combines the light beams modulated by each liquid crystal panel, and a color optical image formed by this optical device is enlarged on the screen A three-plate projector having a projection lens for projecting is known.

Such projectors have been developed to be lighter and more compact so that they can be easily carried and used in various places and opportunities.
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. In addition to downsizing these liquid crystal panels and polarizing plates themselves, the simplification of the mounting structure also reduces the size of the projector and improves the assemblability.
For example, the polarizing plate on the exit side of the liquid crystal panel is directly bonded to the light beam incident end face of the cross dichroic prism, the liquid crystal panel is stored in a container-shaped holding frame having a recess, and the pin shape is formed in the holes formed at the four corners of the holding frame. There has been known an optical device in which a liquid crystal panel and a cross dichroic prism are integrated by inserting a member (see Patent Document 1). With such a configuration, a structure for supporting the liquid crystal panel alone becomes unnecessary, and downsizing and assembling can be improved.

On the other hand, in such a projector, the miniaturization is promoted as described above, and the increase in the brightness of the light source is promoted 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.
Such a problem is not limited to the polarizing plate, and may occur in the same manner even when an optical conversion element having another optical function that easily causes thermal deterioration such as a viewing angle correction plate or a retardation plate is employed. is there.

Conventionally, a cooling method of blowing cooling air taken from the outside to these optical elements such as liquid crystal panels and polarizing plates has been adopted, but the motor noise becomes noise by increasing the size of the cooling fan and increasing the rotation speed, There is a possibility that the presentation may be hindered or the viewer may feel uncomfortable, and the internal heat density increases with the miniaturization and high brightness of the projector, so that the cooling efficiency is limited.
Therefore, the side edges of the two transparent glass plates arranged opposite to each other are connected with a spacer to form a container, and a cooling medium such as ethylene glycol is sealed inside to form a cooling device. A configuration has been proposed in which two in total are arranged on both sides of the liquid crystal panel and are closely attached to the incident side polarizing plate, the liquid crystal panel, and the emission side polarizing plate (Patent Document 2). As a result, cooling is forcibly performed by the cooling device, and further, heat is radiated by conducting the heat of the cooling medium to the spacer.

JP-A-11-160788 (FIGS. 3 and 6) JP-A-11-202411 (Claim 1, paragraphs [0023] [0035], FIG. 1)

  However, in order to manufacture a cooling device as in Patent Document 2, two transparent glass plates, spacers arranged on each side of the glass plate, and a cooling medium are required for each cooling device, and thus Since the cooling device has a complicated structure, the number of parts and the part cost of the optical device increase. Also, a process of assembling a transparent glass plate and a spacer into a container, a process of sealing a cooling medium in the container, a process of closely fixing the cooling device between the liquid crystal panel and the incident side polarizing plate and the emission side polarizing plate, Since a plurality of steps that are difficult to say are required, there is a problem in that it takes time to manufacture the optical device and the manufacturing cost of the entire projector increases.

  In view of the above problems, an object of the present invention is to cope with higher brightness, smaller size, and lower noise of a projector, and can be easily manufactured without increasing manufacturing cost, and mainly a light modulator is sufficiently efficient. It is an object to provide an optical device that can be cooled automatically 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 optical images formed by the respective light modulation devices, wherein heat can be conducted in a holding frame that houses a light modulation element that performs light modulation in the light modulation device And a heat radiating plate made of a heat conductive material that releases the heat generated in the light modulation device to the outside. The heat radiating plate has an out-of-plane direction toward the light beam incident end surface of the color synthesizing optical device. A protruding protrusion is provided, and the light modulation device is fixed to the color synthesizing optical device through the protrusion.

Here, as the heat conductive material of the heat radiating plate, metals such as aluminum, magnesium, copper, iron, titanium, alloys containing them, carbon filler, and the like can be adopted. Arbitrary means such as screwing can be used to fix the heat sink to the light modulation device.
Further, as the material of the protrusion, a material having a low thermal conductivity can be preferably used. The protrusion may be fixed to the color synthesis optical device in any manner. For example, the protrusion may be directly fixed to the light beam incident end surface by means such as adhesion.

According to this invention, the heat generated in the light modulation device by the irradiation of the light beam from the light source is quickly conducted from the light modulation device to the heat radiating plate through the holding frame, and is quickly released from the heat radiating plate to the outside. Therefore, the light modulation device can be radiated and cooled sufficiently effectively. In addition, a heat conductive silicone adhesive or heat conductive grease is interposed between the holding frame / heat radiating plate and the light modulation device, so that the holding frame / heat radiating plate and the light modulation device can be thermally coupled. In this case, the conductive heat dissipation of the heat sink is improved, and the heat dissipation cooling of the light modulation device is further promoted.
This prevents malfunction due to temperature rise of the light modulation device, extends the life of the optical device, prevents deterioration of the image quality of the optical image formed by the optical device, and greatly improves functional reliability. Can do.
Furthermore, since the protrusion extends from the heat sink, there is a gap between the light modulation device and the color synthesizing optical device. When the cooling air is blown into this gap, the cooling air is blown on both sides of the light modulation device. Go around. Therefore, the cooling performance can be further improved without causing temperature unevenness in the light modulation device.

On the other hand, when the optical device is manufactured, it is possible to easily manufacture the optical device without complicating the process only by fixing the heat radiating plate to the light modulation device and fixing the protrusion extending from the heat radiating plate to the color synthesizing optical device. No special equipment or the like is required for production, and the equipment production cost does not increase.
Further, by fixing the heat radiating plate to the light modulation device before the positioning of each light modulation device with respect to the color synthesizing optical device, the light modulation device can be efficiently manufactured without any trouble in the positioning operation.

In the optical device according to the aspect of the invention, it is preferable that the protrusion is a screw shaft member that is screwed into a female screw hole formed in the heat radiating plate.
According to the present invention, the protrusion can be easily formed only by screwing the screw shaft-like member into the female screw hole of the heat radiating plate. Various male screws can be adopted as the screw shaft-like member, and the cost of components can be greatly reduced by using a general-purpose screw for the protrusion.

In the optical device of the present invention, an optical conversion element that performs optical conversion of a light beam modulated by the light modulation device is disposed between the light modulation device and the color synthesis optical device. The holding member is held by a holding member, and the holding member includes a main body portion in which an opening for transmitting a light beam is formed, a pair of upright pieces standing along the optical axis direction from the outer peripheral portion of the main body portion, and the upright pieces It is preferable that the front-end | tip part is bent, and the said protrusion is being fixed to the said main-body part or the said bending piece.
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.
Further, as the material of the holding member, it is preferable to employ a metal such as aluminum, magnesium, copper, iron, titanium, and an alloy containing these, or a material having good thermal conductivity such as a carbon filler.
Note that the protrusion may be fixed to either the main body portion or the bent piece of the holding member.

According to the present invention, by providing the holding member, 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, compared with the case where there is no holding member and the optical conversion element is directly fixed to the color synthesizing optical device, the heat dissipation performance of the optical conversion element can be reliably improved.
In addition, the heat generated in the optical conversion element is quickly released through the holding member, while the heat generated in the light modulation device is also quickly released from the heat sink as described above. The amount of heat that easily enters and exits between the apparatus and the optical conversion element in accordance with the temperature level. In other words, the backflow of heat between the light modulation device and the optical conversion element is prevented, and not only the light modulation device but also the optical conversion element that is likely to be overheated and easily deteriorated due to the absorption of light is sufficiently effectively dissipated. Can be cooled. Here, the heat radiation performance of the optical conversion element can be improved by fixing the heat radiating plate to the incident side rather than the emission side of the light modulation device.

Further, when the projection is directly fixed to the color synthesis optical device, the light modulation device is only partially supported by the light beam incident end face of the color synthesis optical device via the projection, whereas the light modulation device Can be reliably supported on the light beam incident end face of the color synthesizing optical device via a holding member.
Therefore, even when a plurality of optical conversion elements are used, it is possible to withstand the load of these optical conversion elements and firmly fix the light modulation device and the color synthesis optical 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.

And since a pair of standing piece and bending piece are provided in the circumference | surroundings of an optical conversion element, the heat conduction from an optical conversion element to a holding member is performed more effectively. Moreover, the heat dissipation from the holding member can be improved by increasing the heat capacity of the holding member by the size of the standing piece and the bent piece.
In addition, when cooling air is introduced between the light modulation device and the color synthesizing optical device, the cooling air is not stalled by not forming the standing piece and the bent piece at the position where the cooling air flows. Thus, the optical conversion element can be efficiently cooled by flowing inside the holding member.
Furthermore, it becomes possible to hold a plurality of optical conversion elements by using the front and back both sides of the bent piece as joint portions, and the holding capacity of the holding member can be improved.

In the optical device according to the aspect of the invention, it is preferable that the main body portion or the bent piece is provided with a cylindrical portion into which the protrusion is inserted.
Here, the cylindrical portion may be formed integrally with the bent piece, or may be formed separately, and may be integrated with the bent piece by means such as joining. It can use for a cylindrical part. By employing a general-purpose material, the cost can be reduced.

According to this invention, for example, the outer peripheral portion of the protrusion is formed by the cylindrical portion as compared with the case where the end surface of the tip of the protrusion is joined to the outer surface of the holding member or the protrusion is inserted into the hole formed in the holding member. While being supported reliably, the contact area between the protrusion and the holding member can be increased via the cylindrical portion along the direction in which the protrusion of the heat sink protrudes, so that the protrusion and the holding member can be sufficiently joined.
Therefore, the light modulation device can be more reliably supported by the color synthesis optical device via the holding member and the heat dissipation plate.
In addition, since the bonding margin between the protrusion and the cylindrical portion is large, the protrusion and the cylindrical portion can be moved back and forth, and the attitude of the light modulation device with respect to the light beam incident end surface of the color combining optical device can be easily adjusted.
In addition, the shape of the cylindrical portion may protrude from the outer surface of the bent piece to the light modulation device side, or conversely, even if the shape is recessed from the outer surface of the bent piece to the color synthesis optical device side, You may protrude from both front and back sides.

In the optical device according to the aspect of the invention, it is preferable that the heat radiating plate is formed by sheet metal punching, and the cylindrical portion and / or the protrusion is made of a heat insulating material.
Here, as the heat insulating material, a synthetic resin such as acrylic or a glass material such as quartz glass can be employed.
According to this invention, by adopting and processing a sheet metal material for the heat radiating plate, the metal has good thermal conductivity, so that further heat radiation cooling of the light modulation device can be achieved, and by punching, It can be manufactured easily and inexpensively. Further, the cost of the mold is not required for the heat sink, and the component cost can be reduced.
Further, the heat conduction between the heat sink and the holding member joined to each other by the protrusion and the cylindrical portion is cut off, and between the light modulation device and the optical conversion element fixed to each other via the heat sink and the holding member. No heat conduction occurs. Thereby, the thermal backflow between the light modulation device and the optical conversion element does not occur, and the light modulation device and the optical conversion element are thermally independent from each other.
Therefore, it is possible to take cooling means individually, such as quickly releasing the heat generated in the light modulation device from the metal heat sink and sufficiently releasing the heat generated in the optical conversion element from the holding member. Cooling becomes possible.

In the optical device according to the aspect of the invention, it is preferable that a pedestal made of a heat conductive material is provided on an end face that intersects the plurality of light beam incident end faces, and the holding member is connected to the pedestal so as to be able to conduct heat. .
Here, as the thermally conductive material of the pedestal, aluminum, magnesium, copper, iron, titanium, an alloy containing these, or the like can be employed.
According to the present invention, heat can be transferred from the optical conversion element to the pedestal via the holding member, and the heat capacity is increased. Therefore, the optical conversion element can be radiated and cooled more effectively.

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 an optical device as described above.
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. That is, since the optical device has the heat radiation cooling performance as described above, it does not cause malfunction or deterioration due to a temperature rise that easily leads to a decrease in image quality, and the life can be extended.
Therefore, it is possible to cope with downsizing and high brightness without using cooling means such as air blowing that may increase noise, and the functional reliability can be greatly improved.

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 modulators 440R, 440G, and 440B disposed in the downstream of the optical path of each incident-side polarizing plate 444, and the exit side that is disposed in the downstream of the optical path of each of the light modulators 440R, 440G, and 440B and serves as a so-called analyzer. A polarizing plate 630 and a cross dichroic prism 443 as a color synthesis optical device are provided. 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 6 show the optical device main body 48 constituting the optical device 44. FIG. 3 is a view of the optical device body 48 as viewed from above, FIG. 4 is a view as viewed from below, and FIG. 5 is a side view. Further, FIG. 6 shows the light modulation device 440 and the like of the optical device body 48.
The optical device main body 48 includes a cross dichroic prism 443, a pair of pedestals 445 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 a holding member fixed to the pedestal 445. The three holder units 600, the light modulation devices 440R, 440G, and 440B fixed to the holder unit 600 and the three heat radiating plates 700 are provided.

  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 supports and fixes the cross dichroic prism 443 and is a member to which the holder unit 600 is joined. The pedestal 445 is fixed to the upper pedestal 446 fixed to the upper surface of the cross dichroic prism 443 and the lower surface of the cross dichroic prism 443. A lower pedestal 447.
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 good thermal conductivity by a silicone-based thermal conductive adhesive.

Both the upper pedestal 446 and the lower pedestal 447 are members made of aluminum, magnesium, or the like and alloys containing them, and have a substantially rectangular plate shape with an outer dimension slightly larger than the upper surface portion and the lower surface portion of the cross dichroic prism 443. Is formed.
The upper base 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.
The lower pedestal 447 is formed with a concave portion 447A (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.
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, 441B is formed. Magnesium, aluminum, titanium, alloys thereof, It is made of a material having good thermal conductivity, such as a resin material containing a carbon filler.
In addition, heat radiation fins 822 are formed on the surface of the panel holding frame 820 so that heat conducted from the liquid crystal panels 441R, 441G, and 441B is easily radiated through the panel holding frame 820.

As shown in FIG. 6, the heat radiating plate 700 corresponds to the image forming area of the light modulation device 440 and has a rectangular plate in which an opening 701 from which the heat radiating fins 822 of the panel holding frame 820 is exposed is formed at a substantially center. The frame member is fixed to the panel holding frame 820 and releases heat generated in the liquid crystal panels 441R, 441G, 441B to the outside.
The heat radiating plate 700 is formed by sheet metal punching which is easy to manufacture using a metal material having good thermal conductivity such as aluminum, magnesium, titanium, and alloys thereof. In the punching process, holes 710 and 720 (FIG. 5) are drilled at the four corners of the heat sink 700.

Each of these holes 710 is threaded, and only by screwing four screws 711 as screw shaft members into the holes 710 as female threads, the tips of the screws 711 from the plate surface of the heat radiating plate 700. The side protrudes and four protrusions 711A are formed.
The screw 711 is made of transparent acrylic that transmits ultraviolet rays and has heat insulation properties, and a commercially available metric screw (for example, screw diameter is M1.7, length is 6 mm) or the like can be adopted. Also, metal screws other than acrylic screws can be used as long as the pipe member 640 is made of transparent acrylic having heat insulating properties.
In this way, the protrusion 711A is easily and inexpensively formed by screwing the standard screw 711 into the hole 710. Therefore, a protrusion member dedicated to the optical device 44 can be manufactured, or the protrusion member can be used as the heat dissipation plate 700. This eliminates the labor and cost of joining them to each other and facilitates the production.

On the other hand, the holes 720 are formed in the vicinity of the holes 710, respectively. These holes 720 are lower holes that are threaded by insertion of a commercially available metal tapping screw 721. The panel holding frame 820 has a hole (not shown) corresponding to the hole 720, and the heat radiating plate 700 is fixed to the panel holding frame 820 with a tapping screw 721. At the time of fixing, since the heat conductive silicone-based adhesive is filled between the heat radiating plate 700 and the panel holding frame 820 or in the holes 720, the heat radiating plate 700 and the panel holding frame 820 are in close contact with each other. It will be in the state where conduction is performed favorably.
Further, as described above, the heat radiating plate 700 as the heat radiating and cooling mechanism of the light modulation devices 440R, 440G, and 440B can be easily manufactured at low cost using a sheet metal material and a commercially available screw, and the manufacturing process is not complicated. . The heat radiating plate 700 is fixed with screws to the light modulation devices 440R, 440G, and 440B in advance.

Both ends of the holder unit 600 are bonded and fixed to the upper pedestal 446 and the lower pedestal 447 along the light beam incident end face of the cross dichroic prism 443.
As shown in FIG. 4, the holder unit 600 is configured by two channel-shaped members having a substantially C-shaped cross section of the outer holder 610 and the inner holder 620. 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 an alloy thereof, and are combined in a nested manner facing each other. Etc. are held.
Also, the holder unit 600 is provided with four pipe members 640 as cylindrical portions for fixing the light modulation devices 440R, 440G, and 440B.

As shown in FIG. 4, the outer holder 610 includes a rectangular flat plate-shaped main body portion 611 whose both ends are fixed to the upper pedestal 446 and the lower pedestal 447 along the light beam incident end surface of the cross dichroic prism 443, and the main body portion. A pair of upright pieces 612 erected from the left and right ends of 611 toward the out-of-plane direction (optical axis direction). In the main body 611, a substantially rectangular opening (not shown) 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, 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.

Polarizing plates 631 and 632 are fitted into claw members 615 (FIG. 4) and claw members 625 (FIG. 3) formed at the end portions of outer holder 610 and inner holder 620, respectively. Each is held around an opening (not shown) of the holder 620.
Here, the polarizing plates 631 and 632 can be held on both front and back surfaces of the opening (not shown) of the outer holder 610 and the inner holder 620, and even when a plurality of polarizing plates are provided, the holding position is not troubled. Not take. 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. Further, the polarizing plates 631 and 632 can be removed from the claw members 615 and 625 and replaced with new ones even when manufacturing defects or alterations occur in any of them, and are excellent in reworkability.
Note that another type of optical conversion element such as a phase difference plate or a viewing angle correction plate may be set in the outer holder 610 and the inner holder 620. Moreover, the fixed positions of these optical conversion elements can be adjusted according to the color of incident light and various conditions.

Then, the inner holder 620 holding the polarizing plate 632 is inserted inside the outer holder 610 holding the polarizing plate 631 so that the main body portions 611 and 621 face each other, and is inserted into the standing pieces 612 and 622. By engaging the formed irregularities 612A and 622A, the outer holder 610 and the inner holder 620 are combined, and the polarization axes of the polarizing plates 631 and 632 held inside match 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 plate 631, the polarizing plate 632 and the outer holder 610 and the inner holder 620 can be improved.

  As described above, the holder unit 600 in which the polarizing plates 631 and 632 are accommodated is positioned such that the polarizing axes of the polarizing plates 631 and 632 and the polarizing axis of the incident-side polarizing plate 444 are orthogonal to each other, and silicone-based heat conduction is performed. It is fixed to the upper pedestal 446 and the lower pedestal 447 along the light beam incident end surface of the cross dichroic prism 443 by an adhesive or an anaerobic ultraviolet curable adhesive.

  On the other hand, the pipe member 640 is separated from the holder unit 600 as shown in FIG. 6 together with the heat radiating plate 700 and the light modulation device 440. Further, the pipe member 640 is made of transparent acrylic that transmits ultraviolet rays and has heat insulation properties, and the cost is reduced by adopting a general-purpose pipe material.

In this pipe member 640, the protrusion 711A of the heat radiating plate 700 is inserted, and the pipe member 640 and the protrusion 711A are bonded and fixed to each other.
In this fixing operation, first, with respect to the light modulation device 440G facing the projection lens 46, an ultraviolet curable adhesive is applied to the outer peripheral surface of the projection 711A and the end surface of the pipe member 640, and the projection 711A is inserted into the pipe 640. Keep it. Next, the end surface of the pipe member 640 is brought into contact with the bent piece 613 of the outer holder 610.

Then, the projection 711 </ b> A is advanced and retracted inside the pipe member 640, and the light modulation device 440 </ b> G is adjusted to follow the surface tension of the adhesive to adjust the focus surface of the liquid crystal panel 440 </ b> G within the back focus surface of the projection lens 46. Make adjustments. At this time, since the protrusion 711A is supported by the inner peripheral surface of the pipe member 640, the operation can be easily performed.
After positioning the liquid crystal panel 441G in this way, the adhesive is cured by irradiating with ultraviolet rays. At this time, since the ultraviolet rays sufficiently reach the contact portion between the protrusion 711A and the pipe member 640 through the transparent acrylic resin, the adhesive can be quickly cured.
In addition, since the material of the projection 711A and the pipe member 640 is the same acrylic material, peeling of the adhesive due to thermal expansion is prevented.

When the light modulation device 440G is fixed in this manner, the light modulation devices 440R and 440B are similarly adjusted in focus, and the end surface of the pipe member 640 is slid on the bent piece 613 of the outer holder 610, whereby the liquid crystal panel 441G. As a reference, alignment adjustment of the liquid crystal panels 441R, 441G, and 441B is performed.
In the process of focus / alignment adjustment, the ultraviolet curable adhesive is filled between the pipe member 640 and the protrusion 711 </ b> A, and is also filled between the pipe member 640 and the bent piece 613. As described above, the pipe member 640 may be filled with an adhesive without applying the adhesive to the protrusion 711A, or the adhesive may be applied to the protrusion 711A during focus / alignment adjustment. Alternatively, the pipe member 640 may be filled.

  Here, as described above, the heat radiating plate 700 is fixed to the light modulation devices 440R, 440G, and 440B in advance, and the heat radiation plate 700 is fixed to the light modulation devices 440R, 440G, and 440B. Since the positioning work such as the focus / alignment adjustment of 440B is not affected, the work efficiency is not impaired.

As described above, one end of the pipe member 640 is bonded and fixed to the bent piece 613, the pipe member 640 is integrated with the outer holder 610, and the protrusion 711A is fixed to the pipe member 640, whereby the light modulation device 440R, 440G and 440B are fixed to the holder unit 600 through the heat sink 700. The light modulation devices 440R, 440G, and 440B are fixed to be opposed to the light incident end face of the cross dichroic prism 443 through the holder unit 600, the upper pedestal 446, and the lower pedestal 447.
Thus, since the projection 711A is inserted and fixed to the pipe member 640, the end surface of the projection 711A (the end surface of the screw 711) is directly joined to the bent piece 613 or in the hole formed in the bent piece 613. The contact area between the protrusion 711A and the outer holder 610 can be increased via the pipe member 640 in the direction in which the protrusion 711A protrudes, compared to the case where the protrusion 711A is inserted.
Thereby, the heat sink 700 and the outer holder 610 can be sufficiently bonded with a sufficient bonding area, and the polarizing plates 631, 632, the outer holder 610, the inner holder 620, the heat sink 700, and the light modulation devices 440R, 440G, It can withstand a load of 440B, leading to an improvement in impact resistance of the projector 1.

  In summary, the light modulation devices 440R, 440G, and 440B are attached to the cross dichroic prism 443 via the holder unit 600. Accordingly, when the protrusion 711A is directly fixed to the cross dichroic prism 443, the light modulation devices 440R, 440G, and 440B are only partially supported by the cross dichroic prism 443, whereas the holder unit 600 is provided on the upper pedestal. The light modulation devices 440R, 440G, and 440B can be reliably supported by the cross dichroic prism 443.

  Here, instead of providing the pipe member 640 in the holder unit 600, the pipe member 640 is substituted by burring processing in which the body portion 611 of the outer holder 610 is perforated and the periphery of the formed hole protrudes in the out-of-plane direction. It is also conceivable to form the tubular part integrally with the outer holder 610. As a result, the outer holder 610 and the pipe member 640 can be easily formed by sheet metal processing, and when the protrusion 711A is inserted into the cylindrical portion, air is released from the burring hole, and the adhesive is filled from the burring hole. Therefore, work efficiency can be improved.

  A light beam enters the optical device main body 48 described above via the incident-side polarizing plate 444, and the incident light is transmitted through the liquid crystal panels 441R, 441G, and 441B, and further the polarizing plate of the emission-side polarizing plate 630. 631 and 632, and enters the cross dichroic prism 443. At this time, the temperatures of the liquid crystal panels 441R, 441G, and 441B, the polarizing plates 631 and 632 of the exit side polarizing plate 630, and the cross dichroic prism 443 are increased. There is a possibility that deterioration due to alteration of the organic materials used for 441B and the polarizing plates 631, 632 and the like may occur. When the liquid crystal panels 441R, 441G, and 441B deteriorate, color unevenness is likely to occur, and when the polarizing plates 631 and 632 deteriorate, a light leakage phenomenon that does not absorb the light beam and easily transmits it may occur. There is a risk of image quality degradation.

Here, looking at the heat generated in the liquid crystal panels 441R, 441G, 441B, the polarizing plates 631, 632, and the cross dichroic prism 443, the heat generated in the liquid crystal panels 441R, 4441G, 441B is retained by the panel. The heat is quickly conducted to the heat radiating plate 700 through the frame 820. Then, the heat is quickly released into the cooling air from the surface of the heat radiating plate 700 and the heat radiating fins 822 under good thermal conductivity of the material.
Further, the heat generated in the polarizing plates 631 and 632 is conducted to the holder unit 600, is conducted to the upper pedestal 446 and the lower pedestal 447, and is also 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, the heat generated in the polarizing plates 631 and 632 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, so that the heat capacity increases and the cooling air and The contact area increases, and heat exchange with the cooling air becomes efficient.
Then, 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, and is released.

In this way, the heat generated in the liquid crystal panels 441R, 441G, 441B, the polarizing plates 631, 632, and the cross dichroic prism 443 is dissipated, so that the liquid crystal panels 441R, 441G, 441B, the polarizing plates 631, 632, The amount of heat entering and leaving the cross dichroic prism 443 decreases.
In addition, the projections 711A and the pipe member 640 that fix the light modulation devices 440R, 440G, and 440B and the emission-side polarizing plate 630 are heat insulating materials and do not conduct heat, and the light modulation devices 440R, 440G, and 440B side. And the exit side polarizing plate 630 and the cross dichroic prism 443 side are thermally independent.

That is, it is possible to prevent thermal backflow between the light modulation devices 440R, 440G, and 440B side and the exit side polarizing plate 630 and the cross dichroic prism 443 side, and heat generated in the liquid crystal panels 441R, 441G, and 441B is transmitted from the heat radiating plate 700. Cooling means can be taken individually so that heat can be quickly dissipated and the heat generated in the polarizing plates 631 and 632 can be sufficiently dissipated from the holder unit 600, and effective cooling is possible.
Therefore, the durability and the life of the polarizing films of the liquid crystal panels 441R, 441G, and 441B and the polarizing plates 631 and 632 are improved, and the deterioration of image quality due to thermal degradation is prevented, thereby improving the functional reliability. be able to.

[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 shown by the arrows in FIG. 1, the cooling air guided into the optical component casing 47 flows from the lower side to the upper side of the optical device 44 as a result of rectification, and passes through the front and back sides of the liquid crystal panel 441G. The pedestal 445, the holder unit 600, the light modulation devices 440R, 440G, and 440B, and the incident-side polarizing plate 444 and the like flow to the upper side of the optical device body 48 while cooling.

At this time, the light modulation devices 440R, 440G, and 440B and the holder unit 600 are spaced apart from each other via the protrusion 711A of the heat radiating plate 700, and the cooling air flows into the separated portions vigorously, and the liquid crystal panels 441R and 441G. , 441B, and the polarizing plates 631 and 632 as a whole.
Further, the outer holder 610 and the inner holder 620 have a substantially C-shaped cross section, and the cooling air is rectified inside the main body portions 611, 621, the standing pieces 612, 622, and the bent pieces 613, 623, and the polarizing plate 631, Since cooling air flows along the plate surface 632, temperature unevenness does not occur in the polarizing plates 631 and 632, and the cooling effect is further enhanced.
Therefore, the light modulators 440R, 440G, and 440B and the exit-side polarizing plate 630 are efficiently cooled by the two systems of the cooling mechanism by introducing the cooling air and the heat radiation cooling mechanism described above. Even without increasing the air volume of the circulating cooling air, the projector 1 in which the optical device 44 is incorporated does not hinder the increase in brightness, size, and noise.

  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 heat radiating plate, the protrusion, the holding member, the cylindrical portion, and the pedestal are not limited to those of the above embodiment.
Considering the miniaturization of the optical device and the projector, if the heat radiating plate is formed in a size larger than that of the light modulation device, the heat radiation performance can be improved.
Further, the projection may be a straight pin without a thread groove or the like, and may have a hollow shape such as a cylindrical shape as long as the outer shape is a projection / convex shape. Further, as in the above-described embodiment, the screw 711 separate from the heat radiating plate 700 can be adopted as the protrusion, while the protrusion can be integrally formed with the main body of the heat radiating plate.

The light modulation device is only required to be fixed to the color synthesizing optical device through the protrusions of the heat radiating plate, and the object of the present invention can be achieved without a holding member, a cylindrical portion, a pedestal or the like. A protrusion may be directly joined to the light beam incident end face of the color combining optical device, or a protrusion may be inserted into a hole formed in the holding member.
Further, the portion where the protrusion is supported by the cylindrical portion may be any portion from the base end to the tip end of the protrusion.
When a pedestal is provided, the lower part of the pedestal may be fixed to the projector housing.

Here, the fixing manner of the protrusions is not limited to the adhesive fixing as in the above embodiment. For example, by forming the protrusion into a barrel shape and inserting it into the cylindrical part to engage, or forming a small protrusion on the surface of the protrusion and engaging with the concave part formed on the inner surface of the cylindrical part, It may be fixed.
When the protrusion is inserted into the cylindrical portion, the diameters of the protrusion and the cylindrical portion can be arbitrarily set within a range in which the protrusion can be inserted into the cylindrical portion. When the cylindrical part is loose relative to the diameter of the protrusion, the protrusion can be tilted in the cylindrical part by making use of the contact dimension in the optical axis direction between the protrusion and the cylindrical part. And alignment adjustment can be performed more easily and with higher accuracy.
Further, when an adhesive is used for fixing the protrusion and the cylindrical portion, it is conceivable to form a groove or the like that becomes a reservoir portion of the adhesive in the cylindrical portion or the protrusion.

The light modulation device only needs to be directly and indirectly fixed and attached to the color synthesis optical device through the protrusions of the heat radiating plate, and heat is radiated through the holder unit 600 and the base 445 as in the above embodiment. The projection of the plate can be fixed to the color synthesizing optical device, and the projection of the heat radiating plate can be fixed to the light beam incident end face of the color synthesizing optical device via a plate-like fixing member without providing a holding member. .
Moreover, the mutually fixed aspect of a heat sink, a light modulation apparatus, a holding member, protrusion, and a cylindrical part is not limited to the thing of the said embodiment. For example, the fixing of the heat radiating plate to the light modulation device is not limited to a tapping screw or the like, and a fixing means such as a screw screwed into a screw hole or a double-sided tape can also be employed.
And like the said embodiment, a heat conductive silicone type adhesive agent and the heat sink 700, the panel holding frame 820, the outer side holder 610, the inner side holder 620, protrusion 711A, and the mutual fixing part of the pipe member 640 are mutually attached. Thermally conductive grease or the like can be filled to improve the thermal conductivity.
The position where the heat radiating plate is fixed to the light modulation device may be on the incident side or the emission side of the light modulation device.

Various modes can be adopted for the shape, position, number, size, material, and the like of the cylindrical portion into which the protrusion is inserted. The cylindrical portion can have any shape based on a cylindrical shape, such as a semi-cylindrical shape or a petal shape, in addition to the pipe shape exemplified in the embodiment.
Further, the cylindrical portion is not limited to the one protruding in the out-of-plane direction of the holding member, and may be formed so as to be recessed from the surface of the holding member.
Furthermore, it is also conceivable to provide the same cylindrical portion formed on the holding member on the holding frame or the heat radiating plate of the light modulation device.

The type of the optical conversion element is not limited to the polarizing plate, the viewing angle correction plate, and the retardation plate exemplified in the above embodiment, and various elements that convert optical characteristics can be adopted. The number of these optical conversion elements used is not limited, and other types of optical conversion elements may be combined. In the embodiment, optical conversion elements such as the polarizing plates 631 and 632 may be bonded and fixed to the bent pieces 613 and 623.
The above embodiment is a so-called normally white mode in which an all white image is formed when no voltage is applied, and the polarizing plates 631 and 632 are arranged so that their polarization axes are orthogonal to each other. A mode may be adopted so that the polarizing axes of the polarizing plates 631 and 632 are parallel to each other.
The fixing mode of these optical conversion elements is not particularly limited. For example, a groove is formed in the holding member, the optical conversion element is inserted into the groove, or the optical conversion element is formed on the light beam incident end face of the color synthesis optical device. May be attached directly. Although a member for supporting the optical conversion element alone may be provided, the optical conversion element is included in the structure in which the light modulation devices 440R, 440G, and 440B are supported by the cross dichroic prism 443 as in the above embodiment. If the support structure is incorporated, the optical device and the projector can be reduced in size and weight.

In addition to the TN (twisted nematic) type as in the above-described embodiment, various liquid crystals can be used for the light modulation element.
In addition to the light modulation elements using liquid crystals such as the liquid crystal panels 441R, 441G, and 441B, light modulation elements using micro device mirrors and the like can be employed.
Furthermore, the light modulation element may be used by switching from a transmission method using a transparent electrode as in the above embodiment to a reflection method using a reflection electrode as necessary.

As exemplified in the above embodiment, as the heat conductive material, Mg alloy, Al alloy, Mo—Cu alloy, Ti alloy, Fe—Ni alloy, resin material containing carbon filler, and the like can be adopted.
On the other hand, as the heat insulating material, there is a synthetic resin material such as acrylic or a glass material such as quartz glass, but as in the above embodiment, such a heat insulating material is used for the protrusion 711 and the pipe member 640, It is preferable to block the heat conduction between the heat radiating plate 700 side and the holder unit 600 side. It is also conceivable to interpose a heat insulating sheet or the like between the light modulation device and the holding member.
However, a thermally conductive material such as metal can be used for the protrusions and the cylindrical portion. In this case, heat generated by the light modulation device and the optical conversion element can be released to the outside from the heat sink. In this case, a heat conductive adhesive is used for fixing the protrusion and the cylindrical portion, and the fixing can be quickly performed by introducing hot air, a hot beam, or the like.

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

  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 upper direction. 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 light modulation apparatus and heat sink in the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Projector, 44 ... Optical apparatus, 48 ... 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 synthesizing optical device), 445 ... pedestal, 446 ... upper pedestal, 447 ... lower pedestal, 600 ... holder unit (holding member), 610 ... outer holder, 611 ... main body, 612 ... standing piece, 613 ... folding Curved piece, 620 ... inner holder, 621 ... main body, 622 ... standing piece, 623 ... bent piece, 630 ... exit side polarizing plate (optical conversion element), 631, 632 ... polarizing plate, 640 ... pipe member (tubular shape) Part), 700 ... radiator plate, 710 ... hole (female screw hole), 711 ... screw (screw shaft-like member), 711A ... projection, 820 ... panel holding frame (holding frame).

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 holding frame that houses a light modulation element that performs light modulation in the light modulation device includes a heat radiating plate that is connected to be thermally conductive and is made of a heat conductive material that releases heat generated in the light modulation device to the outside.
The heat radiating plate is provided with a protrusion protruding in an out-of-plane direction toward the light beam incident end surface of the color combining optical device,
The optical device, wherein the light modulation device is fixed to the color synthesis optical device through the protrusion. The optical device according to claim 1.
The optical device according to claim 1, wherein the protrusion is a screw shaft-like member that is screwed into a female screw hole formed in the heat radiating plate. The optical device according to claim 1 or 2,
Between the light modulation device and the color synthesizing optical device, an optical conversion element that performs optical conversion of a light beam modulated by the light modulation device is disposed,
As for this optical conversion element, an outer peripheral part is held by a holding member,
The holding member includes a main body portion in which an opening for transmitting a light beam is formed, a pair of upright pieces standing along an optical axis direction from an outer peripheral portion of the main body portion, and a bent portion obtained by bending the tip portion of the upright piece. A piece of music,
The optical device is characterized in that the protrusion is fixed to the main body or the bent piece. The optical device according to claim 3.
An optical device, wherein the main body portion or the bent piece is provided with a cylindrical portion into which the protrusion is inserted. The optical device according to claim 4.
The heat sink is formed by sheet metal punching,
The said cylindrical part and / or the said protrusion are comprised from the heat insulating material, The optical apparatus characterized by the above-mentioned. The optical device according to any one of claims 3 to 5,
A pedestal made of a heat conductive material is provided on an end surface intersecting with the plurality of light beam incident end surfaces,
The optical device is characterized in that the holding member is connected to the pedestal so as to be capable of conducting heat. 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