JP5364997B2 - projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector which can be made thin, while appropriately cooling optical modulators. <P>SOLUTION: The projector includes: liquid crystal panels 251B, 251R and 251G; a cross dichroic prism 254 that takes in respective modulated color light beams from luminous flux incident side end faces and combines them to form image light, and then, emits the image light from the luminous flux exit side end face; and a projection lens 3 that enlarges and projects the image light. The cross dichroic prism 254 is disposed so that the luminous flux incident side end faces and the luminous flux exit side end face can be along the thickness direction of the projector. The projector includes: cooling fans 4 disposed beside the projection lens 3; and a duct section 10 that surrounds the luminous flux incident side end face, and makes the air discharged from the cooling fans flow from the side directions of the liquid crystal panels 251B, 251R and 251G. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a projector including a light modulation device such as a liquid crystal panel.

Conventionally, a light source device, a light modulation device that modulates a light beam emitted from the light source device according to image information, and a color composition that forms a color image (image light) by combining the light beam modulated by the light modulation device A projector including an optical device is known.
In this projector, since a light modulation device such as a liquid crystal panel is generally vulnerable to heat, heat deterioration may occur due to heat generated by irradiation of a light beam from a light source device.
Therefore, a projector (video display device) that includes a cooling fan and a duct that guides air discharged from the cooling fan to the light modulation device and is configured to cool the light modulation device has been proposed (for example, Patent Documents). 1).

The technique described in Patent Literature 1 includes a centrifugal fan and a duct disposed below a light modulation device (light valve). The duct is formed with a flow path (air guide path) that allows the discharge port of the centrifugal fan to communicate with the lower side of the light modulation device. The air discharged from the centrifugal fan is blown onto the light modulation device from below the light modulation device via the flow path. As a result, the light modulation device is cooled.
JP 2005-266833 A

  However, in the technique described in Patent Document 1, since the air flow path is formed below the light modulation device, the portion where the light modulation device is disposed and the periphery thereof secure an air flow path. There is a problem of becoming thicker.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a projector that can be thinned while appropriately cooling the light modulation device.

The projector according to the present invention includes three first to third light modulators that modulate the first to third color lights according to image information, respectively, and three first to third light modulators. A color combining optical device that has a light beam incident side end surface, combines the color lights modulated by the first to third light modulation devices to form and emit image light, and projection optics for projecting the image light A first cooling fan and a second cooling fan, which are disposed at positions opposite to each other across the projection optical device on the side of the projection optical device and discharge air to the first to third light modulation devices a cooling fan, surrounds the three light-incident surface, the first cooling fan and said discharged air from the second cooling fan, respectively, the first light modulator and the third light The second side from the side of the modulation device. A duct portion that circulates in the light modulation device, and the duct portion has a U-shape in plan view surrounding the three light beam incident side end surfaces, and the air discharged from the first cooling fan is The air flowing from the first light modulation device toward the second light modulation device and discharged from the second cooling fan is directed from the third light modulation device to the second light modulation device. And the air discharged from the first cooling fan and the second cooling fan collide with each other at the position where the second light modulation device is disposed in the duct portion, and the first light modulation One of the apparatus and the third light modulation device is configured with a green light modulation device that modulates green light according to image information, and the other is configured with a blue light modulation device that modulates blue light according to image information. And the second light modulation device converts red light into an image. Characterized in that it is composed of a red light modulation device for modulating in accordance with the distribution.
Here, the side means a direction orthogonal to the thickness direction of the projector. That is, the duct part circulates air in a direction orthogonal to the thickness direction of the projector. The duct portion allows air to flow not only to all the light modulation devices but also to at least two adjacent light modulation devices.

According to this configuration, the air discharged from the first cooling fan and the second cooling fan disposed on the side of the projection optical device is transferred to the sides of the first light modulation device and the third light modulation device. Accordingly, since the duct portion is provided to flow to the second light modulation device adjacent to these , each light modulation device can be cooled by applying air from the side to each light modulation device. Accordingly, the light modulation device can be cooled without providing an air flow path or a cooling fan above and below the light modulation device, so that the projector can be thinned.
Further, according to this configuration, the duct portion has a U-shape in a plan view surrounding the three light beam incident side end faces, and the first cooling fan and the second cooling fan are respectively located on the side of the projection optical device. Has been placed. The air discharged from the first cooling fan, the second optical modulator device from the first light modulator, the air discharged from the second cooling fan, the third optical modulators a second optical modulator, is circulated from the respective side. As a result, it is possible to secure a sufficient air volume for cooling the three light modulation devices, so that all the light modulation devices can be efficiently cooled.

In the projector, one of the first light modulation device and the third light modulation device includes a green light modulation device that modulates green light according to image information, and the other uses blue light as image information. The second light modulation device is configured by a red light modulation device that modulates red light according to image information.

According to this configuration, the red light modulation device is disposed downstream of the other light modulation devices in the duct portion. For example, when three light modulation devices are arranged in the air flow path, the red light modulation device is arranged on the most downstream side, and two of the red light modulation device and the green light modulation device or the blue light modulation device are arranged. In doing so, the red light modulation device is arranged downstream of the other light modulation devices. Since red light has lower energy than other color lights, the temperature rise of the red light modulation device is smaller than that of the light modulation devices of other color lights. Therefore, even if it arrange | positions downstream from another light modulation apparatus, it is maintained at the same temperature as another light modulation apparatus. On the other hand, the other light modulation device in which the temperature rise due to the color light is larger than that of the red light modulation device is arranged upstream of the red light modulation device. Since air having a temperature lower than that on the downstream side flows on the upstream side, the light modulation device disposed in the air flow path is efficiently cooled.

In this projector, the first between the light modulator and the second optical modulation apparatus, and, in each of between the third light modulating device and the second optical modulation apparatus, upstream It is preferable that an air guide portion for guiding the air circulated along the light modulation device to the second light modulation device is provided.
The projector includes a holding member that is provided between the light incident side end surface and the light modulation device, and holds the light modulation device so as to face the light beam incident side end surface. It is preferable that a vent hole for allowing air to flow from the side of the light incident side end face is provided and constitutes a part of the duct portion.

The projector includes a holding member that is provided between the light incident side end surface and the light modulation device, and holds the light modulation device so as to face the light beam incident side end surface. It is preferable that a vent hole for allowing air to flow from the side of the light incident side end face is provided and constitutes a part of the duct portion.
According to this configuration, the holding member constitutes a part of the duct portion and is provided with the vent hole through which air is circulated from the side of the light incident side end surface. Air can also be circulated to and from the apparatus. This makes it possible to cool the light modulation device more efficiently.

In this projector, in the duct portion, it is preferable that the holding member before Symbol second optical modulator which hole is provided for discharging the air.

In this projector, each of the first cooling fan and the second cooling fan is configured by a sirocco fan that discharges air taken in along the rotation axis in a rotation tangential direction, and the rotation axis is the thickness of the projector. It is preferable that they are arranged along the direction.

According to this configuration, the first cooling fan and the second cooling fan are configured by sirocco fans, and are arranged so that the rotation axis of the blades is along the thickness direction of the projector. Accordingly, each sirocco fan is arranged in a posture in which the area occupied by the sirocco fan is minimized in the thickness direction of the projector, and thus the projector can be thinned.

[First Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Main components of the projector]
FIG. 1 is a diagram schematically showing a schematic configuration of the projector in the first embodiment, and is a plan view seen from above.
The projector modulates a light beam emitted from a light source according to image information to form image light, and enlarges and projects this image light on a screen (not shown) or the like.
As shown in FIG. 1, a projector 1 includes an optical unit 2, a projection lens 3 as a projection optical device, a cooling fan 4 that discharges air to the optical unit 2, and an exhaust fan that exhausts warm air inside the projector 1 to the outside. 5. An exterior housing or the like for housing these device bodies and constituting an exterior is provided.
Although not shown in FIG. 1, a power supply unit that supplies power to each component in the projector 1 in a space other than the optical unit 2, the projection lens 3, the cooling fan 4, and the exhaust fan 5. , And a control device for controlling each component in the projector 1 are arranged. In the following, for convenience of explanation, the right side in FIG. 1 is described as “right” and the left side is described as “left”. The side on which the projection lens 3 is disposed is referred to as “front”, and the opposite side is referred to as “rear”. A direction orthogonal to the thickness direction of projector 1 (the direction orthogonal to the paper surface of FIG. 1) is described as “side”.

  The optical unit 2 is a unit that forms image light corresponding to image information by optically processing the light beam emitted from the light source 211 under the control of the control device. The optical unit 2 includes a light source device 21, an illumination optical device 22, a color separation optical device 23, a relay optical device 24, an optical device 25, and an optical component for arranging these optical components 21 to 25 at predetermined positions. And a housing 6.

  The light source device 21 is disposed on the left rear side, and includes a light source 211, a reflector 212, and the like. The light source device 21 emits the light beam emitted from the light source 211 toward the illumination optical device 22 with the emission direction being aligned by the reflector 212.

  The illumination optical device 22 includes a first lens array 221, a second lens array 222, a polarization conversion element 223, and a superimposing lens 224. The light beam emitted from the light source device 21 is divided into a plurality of partial light beams by the first lens array 221 and forms an image in the vicinity of the second lens array 222. Each partial light beam emitted from the second lens array 222 is incident so that its central axis (principal light beam) is perpendicular to the light beam incident side end face of the polarization conversion element 223, and the polarization conversion element 223 emits approximately one type of light beam. It is emitted as linearly polarized light. A plurality of partial light beams emitted from the polarization conversion element 223 as linearly polarized light and passed through the superimposing lens 224 are superimposed on three liquid crystal panels 251B, 251R, and 251G described later of the optical device 25.

The color separation optical device 23 includes two dichroic mirrors 231 and 232 and a reflection mirror 233, and a plurality of partial light beams emitted from the illumination optical device 22 by the dichroic mirrors 231 and 232 and the reflection mirror 233 are firstly displayed. (Blue), second (red), and third (green) have a function of separating into three color lights.
The relay optical device 24 includes an incident side lens 241, a relay lens 243, and reflection mirrors 242 and 244. It has a function of leading to the panel 251G.

  The optical device 25 modulates an incident light beam according to image information to form image light. The optical device 25 includes three incident-side polarizing plates 252B, 252R, and 252G for each color light, and an optical device body 26 described later.

  The three incident-side polarizing plates 252B, 252R, and 252G transmit only polarized light having substantially the same polarization direction as the polarization direction aligned by the polarization conversion element 223 among the light beams separated by the color separation optical device 23. Other light beams are absorbed, and the transmitted light beams are emitted to the optical device main body 26.

  The optical component housing 6 includes a housing lower portion 61 that constitutes a lower portion and a housing upper portion 62 (see FIG. 2) that constitutes an upper portion. The optical component housing 6 includes an optical device housing portion 70 (see FIG. 2) for housing the optical device body 26. The optical device storage unit 70 will be described in detail later.

  The projection lens 3 is arranged in front of the optical unit 2 and is configured as a combined lens in which a plurality of lenses are combined. The projection lens 3 enlarges and projects the image light formed by the optical unit 2 on the screen.

The cooling fan 4 includes two sirocco fans 41 and 42, takes in air outside the projector 1, discharges the taken-in air to the optical device housing 70, and cools the optical device 25. The sirocco fans 41 and 42 are vanes that have blades that rotate inside and discharge the air taken in along the rotation axis in the rotational tangential direction.
The sirocco fans 41 and 42 are arranged on the side of the projection lens 3 at positions facing each other with the projection lens 3 interposed therebetween. The sirocco fans 41 and 42 have postures in which the intake ports 411 and 421 face downward and the discharge ports 412 and 422 face rearward, respectively. As described above, the sirocco fans 41 and 42 are arranged so that the rotation axis of the blades is along the thickness direction of the projector 1.

  The exhaust fan 5 is disposed in front of the left side and exhausts air that has been cooled by cooling the optical components and air that has been heated due to the heat generated by irradiation of the light beam from the light source 211 to the outside of the projector 1.

Next, the configuration of the optical device main body 26 and the optical device storage unit 70 will be described in order.
FIG. 2 is a perspective view of the front side of the optical component housing 6 as viewed from the front upper side. Specifically, FIG. 2 is a diagram illustrating the optical device main body 26 and the optical device housing portion 70 in a state where the housing upper part 62 is opened.
3 and 4 are cross-sectional views showing configurations of the optical device main body 26 and the optical device housing portion 70. FIG. Specifically, FIG. 3 is an AA cross-sectional view in FIG. 4 is a cross-sectional view taken along the line BB in FIG.

[Configuration of optical device body]
As shown in FIGS. 1 and 2, the optical device body 26 is arranged on the first side to the third light modulation device that modulates the first to third color lights according to the image information, respectively, on the rear side of each optical path. Three exit side polarizing plates 253B, 253R, and 253G, a cross dichroic prism 254 as a color synthesizing optical device, and holding members 8R and 8BG.

  Each of the first to third light modulation devices includes liquid crystal panels 251B, 251R, and 251G, and has a configuration in which liquid crystal that is an electro-optical material is hermetically sealed between a pair of transparent glass substrates. The alignment state of the liquid crystal is controlled in accordance with a drive signal from the apparatus, and the polarization direction of each polarized light beam emitted from the incident side polarizing plates 252B, 252R, and 252G is modulated.

  The three exit-side polarizing plates 253B, 253R, and 253G have substantially the same function as the incident-side polarizing plates 252B, 252R, and 252G, and the light beams emitted through the liquid crystal panels 251B, 251R, and 251G have a certain direction. The polarized light is transmitted, and other light beams are absorbed and emitted to the cross dichroic prism 254.

The cross dichroic prism 254 synthesizes each color light emitted from the exit side polarizing plates 253B, 253R, and 253G to form a color image.
The cross dichroic prism 254 has a substantially square shape in plan view in which four right angle prisms are bonded together, and two dielectric multilayer films are formed on the interface where the right angle prisms are bonded together. The cross dichroic prism 254 has three light beam incident side end surfaces 254B, 254R, and 254G and one light beam emission side end surface 254S.

  The cross dichroic prism 254 is disposed such that the light exit side end surface 254S is the front, the light incident side end surface 254B is the left side, the light incident side end surface 254R is the rear side, and the light incident side end surface 254G faces the right side. As described above, the cross dichroic prism 254 is arranged such that the light beam incident side end surfaces 254B, 254R, 254G and the light beam emission side end surface 254S are along the thickness direction of the projector 1. Then, liquid crystal panels 251B, 251R, 251G, and emission side polarizing plates 253B, 253R, 253G are arranged to face each other on the light incident side end faces 254B, 254R, 254G. Thus, the liquid crystal panels 251B, 251R, and 251G are adjacently arranged in this order.

  The cross dichroic prism 254 is a dielectric multilayer film that transmits the color light emitted from the liquid crystal panel 251R, reflects the color lights emitted from the liquid crystal panels 251B and 251G, and combines the color lights to form image light. To do. The image light formed by the cross dichroic prism 254 is emitted to the projection lens 3 from the light beam emission side end face 254S.

  As shown in FIG. 3, the holding member 8R is provided between the light incident side end face 254R and the liquid crystal panel 251R, and holds the liquid crystal panel 251R so as to face the light incident side end face 254R. The holding member 8R includes an incident side member 81R and an emission side member 82R.

The incident side member 81R is a plate-like member having an L-shaped cross section. The upper end side and the lower end side of the liquid crystal panel 251R are on the light beam incident side end surface 254R side above and below the surface on the light beam incident side end surface 254R side. It is attached to protrude.
The emission-side member 82R is a plate-like member having a hole through which red light passes at the center, and having an upper end and a lower end bent in the same direction in an L shape. The exit-side member 82R has a surface opposite to the bending direction attached to the light beam incident-side end surface 254R.
The outer dimension of the upper and lower bent parts of the incident side member 81R attached to the liquid crystal panel 251R is smaller than the inner dimension of the upper and lower bent parts of the emission side member 82R. The upper and lower incident-side members 81R are attached so as to overlap the upper and lower bent portions of the emission-side member 82R, so that the liquid crystal panel 251R is disposed to face the light-incident-side end surface 254R. In addition, holes 811 and 821 are provided at substantially the same positions in the bent portion of the upper end of the emission side member 82R and the protruding portion of the upper incident side member 81R.

As shown in FIG. 4, the holding member 8BG is provided between the light beam incident side end surface 254B and the liquid crystal panel 251B, and between the light beam incident side end surface 254G and the liquid crystal panel 251G, and the liquid crystal panels 251B and 251G are provided as light beams. The incident side end faces 254B and 254G are held opposite to each other. The holding member 8BG includes an incident side member 81BG and an emission side member 82BG, similarly to the holding member 8R.
The incident side member 81BG is not provided with a hole 811 with respect to the incident side member 81R, and the other portions are formed in the same shape. Further, the injection side member 82BG is not provided with a hole 821 with respect to the injection side member 82R, and the other portions are formed in the same shape.

As shown in FIG. 3, the emission side polarizing plate 253R for red light is attached to the inner surface of the emission side member 82R and has a gap with the liquid crystal panel 251R.
Since there are no projecting portions on both side surfaces of the incident side member 81R and the emission side member 82R, the liquid crystal panel 251R and the emission side polarizing plate 253R are in a state where the emission side member 82R is attached to the incident side member 81R. Is formed with a vent hole 83R through which air flows from the side along the light incident side end face 254R.

As shown in FIG. 4, similarly, the emission side polarizing plates 253B and 253G for blue light and green light are respectively attached to the inner surface of the emission side member 82BG, and have gaps with the liquid crystal panels 251B and 251G, respectively. doing. Therefore, in the state where the emission side member 82BG is attached to the incident side member 81BG, similarly, between the liquid crystal panel 251B and the emission side polarizing plate 253B and between the liquid crystal panel 251G and the emission side polarizing plate 253G, Ventilation holes 83B and 83G are formed to allow air to flow from the sides along the light beam incident side end faces 254B and 254G, respectively.
As described above, the holding member 8R and the holding member 8BG hold the liquid crystal panels 251B, 251R, and 251G so as to face the light beam incident side end surfaces 254B, 254R, and 254G, respectively, and the liquid crystal panels 251B, 251R, and 251G side. From the side, it has a function as an exit side duct part for circulating air to the exit side.

[Configuration of optical device storage section]
As shown in FIG. 2, the housing lower portion 61 has an opening on the upper side, and the optical device body 26 is disposed on the front side. The housing upper part 62 is a member that closes the opening of the housing lower part 61.
The housing lower part 61 includes a device housing lower part 71.
The device storage lower portion 71 includes a lower portion that covers the lower portion of the optical device body 26, and an outer peripheral wall portion that protrudes upward from the lower portion and is provided so as to cover the outer periphery of the optical device body 26 and has a flat upper surface. Have.
The housing upper part 62 has a device housing upper part 72 that closes the opening of the device housing lower part 71. The device storage lower portion 71 and the device storage upper portion 72 are referred to as an optical device storage portion 70.

First, details of the device storage lower portion 71 will be described.
The outer peripheral wall portion has a U-shaped wall portion 711 that is U-shaped in a plan view on the rear side and an I-shaped wall portion 712 that is I-shaped in a plan view on the front side.
The U-shaped wall portion 711 is formed with three openings 713 that allow light of each color to pass therethrough and grooves 714 for holding the incident-side polarizing plates 252B, 252R, and 252G.
As shown in FIGS. 3 and 4, the entrance side polarizing plates 252 </ b> B, 252 </ b> R, and 252 </ b> G are inserted into the grooves 714, respectively, and the opening 713 is closed. Further, the incident-side polarizing plates 252B, 252R, and 252G have gaps 84B, 84R, and 84G, respectively, with respect to the liquid crystal panels 251B, 251R, and 251G.

  As shown in FIG. 3, a hole 715 through which image light emitted from the cross dichroic prism 254 passes is formed in the I-shaped wall portion 712, and the projection lens 3 is attached to the peripheral portion of the hole 715. It has been. In addition, openings 716 and 717 are formed on both sides of the hole 715 as shown in FIG. The openings 716 and 717 communicate with the discharge ports 412 and 422 of the sirocco fans 41 and 42, respectively, and have a function as an inflow port for allowing air to flow into the optical device storage unit 70.

  As shown in FIGS. 2 and 3, guide ribs 718 and 719 are provided on the rear side of the I-shaped wall portion 712 so as to protrude toward the light emission side end surface 254 </ b> S at the same height as the I-shaped wall portion 712. Yes. The guide rib 718 is provided between the opening 716 and the hole 715, and the guide rib 719 is provided between the opening 717 and the hole 715, and each extends to the vicinity of the light emission side end face 254S.

Next, the configuration of the device storage upper portion 72 will be described in detail.
As shown in FIGS. 2 to 4, holes 72 </ b> B, 72 </ b> R, and 72 </ b> G are formed in the device storage upper portion 72 at positions corresponding to the liquid crystal panels 251 </ b> B, 251 </ b> R, and 251 </ b> G, respectively. FPC cables 251F that connect the liquid crystal panels 251B and 251G to the control device are passed through the holes 72B and 72G, respectively. The hole 72R is larger than the holes 72B and 72G, and is formed to a position corresponding to the incident-side polarizing plate 252R and the emission-side polarizing plate 253R in a plan view viewed from above. The hole 72R has a function as a discharge port through which the FPC cable 251F connecting the liquid crystal panel 251R and the control device is passed and the air in the optical device housing portion 70 is discharged to the outside. In the holes 72B and 72G, sealing members 72C made of rubber, sponge or the like for sealing the gaps between the FPC cables 251F are arranged.

Next, a configuration in which the optical device body 26 is attached to the optical device housing portion 70 will be described.
As shown in FIGS. 3 and 4, the cross dichroic prism 254 has a lower portion attached to the support member 255, and the support member 255 is fixed to the device storage lower portion 71 by being attached to the device storage lower portion 71. .
Further, a sealing member 256 formed of rubber, sponge, or the like is disposed between the upper surface of the cross dichroic prism 254 and the inner surface of the apparatus housing upper portion 72 so that air does not flow.
As described above, the optical device storage section 70, the incident side polarizing plates 252B, 252R, and 252G, the cross dichroic prism 254, the support member 255, and the sealing member 256 include the liquid crystal panels 251B, 251R, and 251G and the light beam incident side end surfaces 254B and 254R. , 254G. These constituent members have a function as the incident side duct portion 9 for circulating the air flowing in from the openings 716 and 717 from the side of the liquid crystal panels 251B, 251R, and 251G to the incident side.
The holding members 8R and 8BG and the incident-side duct portion 9 described above constitute a duct portion 10 according to the present invention.

[Air flow in the duct]
Next, the flow of air flowing through the duct portion 10 will be described.
As shown in FIGS. 2 to 4, the sirocco fans 41 and 42 take in external air from an air inlet (not shown) provided in the lower part of the exterior housing, and take the air taken in through openings 716 and 717, respectively. It is made to flow in the duct part 10.
The air that flows in from the opening 716 flows from the front side to the rear side in the duct part 10 (flow path F1). The air flowing through the flow path F1 passes through the gap 84B and the vent hole 83B, and cools the liquid crystal panel 251B, the incident side polarizing plate 252B, and the emission side polarizing plate 253B.

The air that has passed through the flow path F1 changes direction to the right side by the wall on the rear side of the U-shaped wall portion 711 and flows from the left side to the right side (flow path F2). The air flowing through the flow path F2 passes through the gap 84R and the vent 83R, and cools the liquid crystal panel 251R, the incident side polarizing plate 252R, and the emission side polarizing plate 253R.
As described above, the air flowing in from the opening 716 is circulated from the side in the order of the liquid crystal panels 251B and 251R, and is incident on the liquid crystal panels 251B and 251R and the respective incident sides disposed on the front and rear of those optical paths. The polarizing plates 252B and 252R and the exit side polarizing plates 253B and 253R are cooled.

  On the other hand, the air flowing in from the opening 717 flows from the front side to the rear side in the duct part 10 (flow path F4). The air flowing through the flow path F4 passes through the gap 84G and the vent 83G, and cools the liquid crystal panel 251G, the incident side polarizing plate 252G, and the emission side polarizing plate 253G.

The air that has passed through the flow path F4 changes direction to the left side by the wall on the rear side of the U-shaped wall portion 711, and flows from the right side to the left side (flow path F5). The air flowing through the flow path F5 passes through the gap 84R and the vent 83R, and cools the liquid crystal panel 251R, the incident side polarizing plate 252R, and the emission side polarizing plate 253R.
As described above, the air flowing in from the opening 717 is circulated from the side in the order of the liquid crystal panels 251G and 251R, and is incident on the liquid crystal panels 251G and 251R and the respective incident sides disposed on the front and rear of those optical paths. The polarizing plates 252G and 252R and the exit side polarizing plates 253G and 253R are cooled.

The air flowing through the flow path F2 and the flow path F5 merges and is discharged from the hole 72R (flow path F3). In addition, when the air is discharged from the hole 72R, the air that has passed through the vent hole 83R passes through the holes 811 and 821, and is discharged.
The air discharged from the hole 72R follows the inner surface of the exterior housing and is discharged from the exhaust fan 5 to the outside of the projector 1.

As described above, according to the projector 1 of the present embodiment, the following effects can be obtained.
(1) The duct portion 10 surrounds the liquid crystal panels 251B, 251R, 251G and the light beam incident side end faces 254B, 254R, 254G. And the air discharged from the sirocco fans 41 and 42 arrange | positioned at the side of the projection lens 3 is distribute | circulated from the side of liquid crystal panel 251B, 251R, 251G. Further, the liquid crystal panels 251B to 251R and the liquid crystal panels 251G to 251R are circulated in the adjacent order. As a result, the liquid crystal panels 251B, 251R, 251G, the incident side polarizing plates 252B, 252R, 252G, the exit are provided without providing an air flow path or a cooling fan above and below the liquid crystal panels 251B, 251R, 251G. Since the side polarizing plates 253B, 253R, and 253G can be cooled, the projector can be thinned.

  (2) Since the optical component casing 6 constitutes a part of the duct portion 10, the incident side polarizing plates 252B, 252R, 252G, the liquid crystal panels 251B, 251R, 251G and Air can be circulated through the exit-side polarizing plates 253B, 253R, and 253G. As a result, these optical components can be cooled in a space efficient manner, so that the projector 1 can be miniaturized.

  (3) The holding member 8R and the holding member 8BG have vent holes 83B, 83R, 83G, and constitute a part of the duct portion 10. Thereby, air can be circulated between the light incident side end faces 254B, 254R, 254G and the liquid crystal panels 251B, 251R, 251G, which are difficult to circulate, so that the liquid crystal panels 251B, 251R, 251G and The exit-side polarizing plates 253B, 253R, and 253G can be cooled.

  (4) The duct portion 10 has a U-shaped wall portion 711, and the air discharged from the sirocco fans 41 and 42 is side by side in the order of the liquid crystal panel 251B to the liquid crystal panel 251R and the liquid crystal panel 251G to the liquid crystal panel 251R. Circulate from one side. As a result, a sufficient air volume for cooling the three liquid crystal panels 251B, 251R, and 251G can be secured, so that all the liquid crystal panels 251B, 251R, and 251G can be efficiently cooled.

  (5) The liquid crystal panel 251R is disposed downstream of the liquid crystal panel 251B and the liquid crystal panel 251G in the duct portion 10. The temperature rise due to the colored light is higher in the liquid crystal panel 251B and the liquid crystal panel 251G than in the liquid crystal panel 251R, and air having a lower temperature than the downstream side flows in the upstream side, so the three liquid crystal panels 251B, 251R, and 251G It is cooled efficiently.

  (6) The cooling fan 4 is composed of two sirocco fans 41 and 42, and is arranged so that the rotation axis of the blades is along the thickness direction of the projector 1. Accordingly, since the sirocco fans 41 and 42 are arranged in a posture in which the area occupied by the sirocco fans 41 and 42 is minimized in the thickness direction of the projector 1, the projector 1 can be thinned.

  (7) In the duct part 10, the liquid crystal panels 251B and 251G, the incident side polarizing plates 252B and 252G arranged on the upstream side of those optical paths, and the emission side polarizing plates 253B and 253G arranged on the downstream side of the optical path Since there is no opening, it is suppressed that dust etc. fall and adhere to the surface. As a result, the image quality of the projected image can be secured stably.

[Second Embodiment]
Next, 2nd Embodiment of this invention is described based on drawing.
In the following description, the same structure and the same members as those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted or simplified.
In the present embodiment, the air flow in the duct portion 10 is different from that in the first embodiment.

FIG. 5 is a perspective view showing the optical component casing 6 in the second embodiment. Specifically, FIG. 5 is a diagram showing the optical device main body 26 and the optical device housing portion 70 in a state where the housing upper part 62 is opened.
As shown in FIG. 5, the cooling fan 4 is composed of one sirocco fan 42 disposed on the right side of the projection lens 3.
The liquid crystal panels 251B, 251G, and 251R as the first to third light modulation devices are arranged on the right side, the rear side, and the left side with respect to the cross dichroic prism 254, respectively. Thus, the liquid crystal panels 251B, 251G, and 251R are adjacently arranged in this order. The optical components such as the color separation optical device and the relay optical device are configured to correspond to the arrangement of the liquid crystal panels 251B, 251G, and 251R.
The liquid crystal panel 251R is attached to the cross dichroic prism 254 by a holding member 8BG instead of the holding member 8R in the first embodiment.

  The device storage lower portion 71 differs from the first embodiment in the number of inlets and the position of outlets. Specifically, as the inflow port, one opening portion 717 communicating with the discharge port 422 of the sirocco fan 42 is provided, and as the discharge port, a hole 7110 is provided on the left side of the projection lens 3 of the I-shaped wall portion 712. ing.

  The device storage upper portion 72 is different from the first embodiment in the hole 72R. Specifically, the hole 72R is formed in the same size as the holes 72G and 72B, and the sealing member 72C is disposed in the hole 72R.

Next, the air flowing through the duct portion 10 will be described.
The sirocco fan 42 causes air taken in from the outside to flow into the duct portion 10 through the opening 717. The air that has flowed in through the opening 717 flows in the duct portion 10 from the front side toward the rear side (flow path F6). The air flowing through the flow path F6 cools the liquid crystal panel 251B, the incident side polarizing plate 252B, and the emission side polarizing plate 253B.

  The air that has passed through the flow path F6 changes its direction to the left side by the wall on the rear side of the U-shaped wall portion 711, and flows from the right side to the left side (flow path F7). The air flowing through the flow path F7 cools the liquid crystal panel 251G, the incident side polarizing plate 252G, and the emission side polarizing plate 253G (not shown).

The air that has passed through the flow path F7 changes its direction to the front side by the left wall of the U-shaped wall portion 711 and flows from the rear side toward the front side (flow path F8). The air flowing through the flow path F8 cools the liquid crystal panel 251R, the incident side polarizing plate 252R, and the emission side polarizing plate 253R.
And the air which passed the flow path F8 is discharged | emitted from the hole 7110 outside the duct part 10 (flow path F9).
As described above, the air flowing in from the opening 717 is circulated from the side in the order of the liquid crystal panels 251B, 251G, and 251R by the duct portion 10 and discharged from the hole 7110.

  The air discharged from the hole 7110 is changed in the left direction by the rib-like standing wall 100 provided at the lower portion of the exterior housing and is discharged from the exhaust fan 5 to the outside of the projector 1.

As described above, according to the projector 1 of the present embodiment, in addition to the effects (1) to (3), (5), and (6) of the first embodiment, the following effects can be obtained. .
(1) Since the cooling fan 4 is composed of one sirocco fan 42, it is possible to effectively use the space inside the outer casing and to achieve a small size. Further, it is possible to reduce the weight.

  (2) The duct portion 10 has no opening above the liquid crystal panel 251R, the incident-side polarizing plate 252R disposed on the front side of the optical path, and the emission-side polarizing plate 253R disposed on the rear side of the optical path. As a result, dust and the like are further prevented from falling and adhering to the surface, and the image quality of the projected image can be secured stably.

[Modification of Embodiment]
The present invention is not limited to the above-described embodiment, but includes modifications and improvements as long as the object of the present invention can be achieved.
You may provide the discharge port of 1st Embodiment in the position of the apparatus accommodating lower part 71 corresponding to the liquid crystal panel 251R, the incident side polarizing plate 252R, and the emission side polarizing plate 253R. In this case, the hole 72R is formed in the same size as the holes 72G and 72B, and the sealing member 72C is disposed. The holes 811 and 821 are formed on the incident side member 81R and the emission side member 82R. It is preferable to provide the lower L-shaped part instead of the upper part.
As a result, the duct portion 10 has no opening above the liquid crystal panel 251R, the incident-side polarizing plate 252R disposed on the upstream side of the optical path, and the exit-side polarizing plate 253R disposed on the downstream side of the optical path. As compared with the first embodiment, the dust and the like are further prevented from dropping and adhering to the surface. As a result, the image quality of the projected image can be further ensured stably.

  The duct portion 10 of the first embodiment may be formed separately in an I shape and an L shape. For example, a partition is formed between the liquid crystal panel 251B and the liquid crystal panel 251R, and an I-shaped duct portion that allows air to flow through the liquid crystal panel 251B, and an L-shaped duct portion that causes air to flow through the liquid crystal panels 251G and 251R. In the I-shaped duct portion, a discharge port is provided in the upper part on the rear side of the liquid crystal panel 251B. The air discharged from the sirocco fan 41 flows from the front side to the rear side of the I-shaped duct portion to cool the liquid crystal panel 251B. On the other hand, the air discharged from the sirocco fan 42 flows through the L-shaped duct part from the front side toward the rear side, and then flows from the right side toward the left side to cool the liquid crystal panels 251G and 251R. As described above, since air to be circulated can be divided into the objects to be cooled, it becomes easier to control the air volume and flow velocity of the fan in correspondence with the objects, and more efficient cooling and lower noise can be achieved. It becomes possible.

You may provide an air guide part between the adjacent light modulation apparatuses of the said embodiment. For example, the case where an air guide part is formed in the apparatus storage lower part 71 of 1st Embodiment is demonstrated using FIG.
FIG. 6 is a plan sectional view of the duct portion 10.
As shown in FIG. 6, the apparatus housing lower portion 71 includes an air guide portion 711 </ b> B whose cross section protrudes in an L shape between the liquid crystal panel 251 </ b> B and the liquid crystal panel 251 </ b> R and between the liquid crystal panel 251 </ b> R and the liquid crystal panel 251 </ b> G. , 711G are formed respectively. As a result, the air that has flowed through the vent holes 83B and 83G smoothly flows to the vent holes 83R (flow paths F10 and 11), respectively, so that the liquid crystal panel 251R and the exit-side polarizing plate 253R can be cooled more efficiently. In addition, since turbulent flow is suppressed, it is possible to reduce noise.

  The intake port through which the sirocco fans 41 and 42 of the above-described embodiment take outside air may be provided on the side surface side of the exterior housing instead of the lower portion of the exterior housing.

  The sirocco fans 41 and 42 of the embodiment are arranged in a posture in which the discharge port faces the rear side, but may be arranged in a posture in which the discharge port faces in another direction.

  The cooling fan 4 of the embodiment may be an axial fan.

  The optical unit 2 of the first embodiment may have a configuration in which the positions where the liquid crystal panel 251B and the liquid crystal panel 251G face the cross dichroic prism 254 are interchanged.

  The optical unit 2 of the second embodiment is configured such that the positions where the liquid crystal panel 251B and the liquid crystal panel 251R face the cross dichroic prism 254 are interchanged, and the sirocco fan 42 is disposed on the left side of the projection lens 3, and the lower part of the apparatus housing 71 may be configured such that the positions of the opening 717 and the hole 7110 of the 71 are interchanged.

  The present invention can be thinned while appropriately cooling the light modulation device, and can be used for various projectors used for presentations, movie viewing, and the like.

FIG. 2 is a diagram schematically illustrating a schematic configuration of a projector according to the first embodiment. The perspective view which looked at the front side of the housing | casing for optical components of 1st Embodiment from the front upper side. It is sectional drawing which shows the structure of an optical apparatus main body and an optical apparatus accommodating part, and is AA sectional drawing in FIG. It is sectional drawing which shows the structure of an optical apparatus main body and an optical apparatus accommodating part, and is BB sectional drawing in FIG. The perspective view of the housing | casing for optical components of 2nd Embodiment. The plane sectional view of the duct part in a modification.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Projector, 3 ... Projection lens, 4 ... Cooling fan, 6 ... Housing for optical components, 8R, 8BG ... Holding member, 9 ... Incident side duct part, 10 ... Duct part, 41, 42 ... Sirocco fan, 70 ... Optical device housing, 83B, 83G, 83R ... vent, 251B, 251R, 251G ... liquid crystal panel, 252B, 252R, 252G ... incident side polarizing plate, 253B, 253R, 253G ... exit side polarizing plate, 254 ... cross dichroic prism 254B, 254R, 254G ... luminous flux incident side end surface, 254S ... luminous flux emission side end surface, 255 ... support member, 256 ... sealing member.

Claims (5)

First to third light modulators for modulating the first to third color lights according to image information, respectively,
The first to third light modulation devices each have three light beam incident side end faces, and image light is formed by combining the color lights modulated by the first to third light modulation devices. A color synthesizing optical device that emits
A projection optical device for projecting the image light;
A first cooling fan and a second cooling fan which are arranged at positions facing each other across the projection optical device on the side of the projection optical device, and discharge air to the first to third light modulation devices; ,
Surrounds the three light-incident surface, a side of the first the discharged air from the cooling fan and the second cooling fan, respectively, the first light modulation device and the third optical modulators A duct portion that circulates from the side to the second light modulation device,
The duct portion has a U-shape in a plan view that surrounds the three light beam incident side end surfaces,
The air discharged from the first cooling fan circulates from the first light modulation device to the second light modulation device, and the air discharged from the second cooling fan is the third light. The air circulated from the light modulation device toward the second light modulation device, and the air discharged from the first cooling fan and the second cooling fan flows into the second light modulation device in the duct portion. collide at the position,
One of the first light modulation device and the third light modulation device is configured by a green light modulation device that modulates green light according to image information, and the other modulates blue light according to image information. Consists of a blue light modulator,
The projector according to claim 2, wherein the second light modulation device includes a red light modulation device that modulates red light according to image information . The projector according to claim 1, wherein
The first between the light modulator and the second optical modulator, and the third, respectively between the optical modulator and the second optical modulation apparatus, upstream of said optical modulation A projector comprising an air guide for guiding the air circulated along the device to the second light modulation device. In the projector according to claim 1 or 2,
A holding member that is provided between the light beam incident side end face and the light modulation device and holds the light modulation device facing the light beam incident side end face;
The projector according to claim 1, wherein the holding member is provided with a vent hole through which air flows from a side of the end face on the light beam incident side, and constitutes a part of the duct portion. The projector according to claim 3, wherein
In the duct portion, the holding member of the second light modulation device is provided with a hole for discharging the air. In the projector according to any one of claims 1 to 4 ,
Each of the first cooling fan and the second cooling fan is configured by a sirocco fan that discharges air taken in along the rotation axis in a rotation tangential direction, and the rotation axis is along the thickness direction of the projector. A projector characterized by being arranged in

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