JP2021047364A - projector - Google Patents

Abstract

To provide a projector capable of hardly recognizing fluctuations in a projected image.SOLUTION: A projector includes: a light source; an optical modulation device 455R for modulating light LR emitted from the light source; a projection optical device for projecting light modulated by the optical modulation device; a first polarization element 457R arranged on a light emission side of the optical modulation device; a casing 51 for storing at least one optical component of the optical modulation device and the first polarization element and enclosing a cooling liquid therein; and a flow device for flowing the cooling liquid in the at least one optical component. A flow rate of the cooling liquid flowing through an optical emission side of the at least one optical component is smaller than the flow rate of the cooling liquid flowing through an optical injection side of the at least one optical component.SELECTED DRAWING: Figure 3

Description

The present invention relates to a projector.

Conventionally, a liquid crystal display device that projects an image on a screen using a liquid crystal display element is known (see, for example, Patent Document 1).
The liquid crystal display device described in Patent Document 1 is emitted from a light source, a liquid crystal display device in which light of each component of red, green, and blue separated from the light source light emitted from the light source is incident, and a liquid crystal display device. It has a projection lens that projects the image. The liquid crystal display device includes a red light liquid crystal display unit in which red light is incident, a green light liquid crystal display unit in which green light is incident, a blue light liquid crystal display unit in which blue light is incident, and a three-color liquid crystal display unit. It is composed of a prism for synthesizing the above, a cooling container, a refrigerant sealed in the cooling container, and a plurality of stirring means for circulating the refrigerant. Each liquid crystal display unit is composed of an incident side polarizing element, a liquid crystal panel, and an outgoing side polarizing element.

The cooling container has openings on each side wall facing in all directions, and each of the openings is equipped with incident-side polarizing elements for red, green, and blue, and glass.
Of the side surfaces of the prism installed in the cooling container, the side surface facing the incident side polarizing element for red is provided with the emitting side polarizing element for red, and the side surface facing the incident side polarizing element for green is provided. Is provided with an emitting side polarizing element for green, and an emitting side polarizing element for blue is provided on a side surface facing the incident side polarizing element for blue.
A liquid crystal panel for red light is installed between the incident side polarizing element and the outgoing side polarizing element for red, respectively. A liquid crystal panel for green light is installed between the incident side polarizing element and the outgoing side polarizing element for green, respectively. A liquid crystal panel for blue light is installed between the incident side polarizing element and the outgoing side polarizing element for blue, respectively.

Each of the plurality of stirring means is provided at the corner of the cooling container. Each stirring means produces a flow of refrigerant that merges on the heat generating surfaces of the incident side polarizing element, the liquid crystal panel, and the outgoing side polarizing element. When the flow of the refrigerant is disturbed by the merging of the flows of the refrigerant, the temperature boundary layer becomes thin and the heat transfer coefficient is improved, so that the cooling efficiency of the liquid crystal display unit is increased.

Japanese Unexamined Patent Publication No. 2002-131737

However, in the liquid crystal display device described in Patent Document 1, the refrigerant flows along the surface through which light passes in the liquid crystal panel and each polarizing element. The density of the refrigerant changes depending on the temperature, and thus the refractive index changes. When the refractive index distribution of the refrigerant occurs on the surface of the liquid crystal panel and each polarizing element through which light passes, fluctuations are easily recognized in the projected image. That is, the image projected on the screen by the liquid crystal display device is deteriorated.

The projector according to one aspect of the present invention includes a light source, a light modulator that modulates the light emitted from the light source, a projection optical device that projects light modulated by the optical modulator, and the optical modulator. A first polarizing element arranged on the light emitting side, a housing containing at least one of the optical modulator and the optical component of the first polarizing element, and a cooling liquid sealed therein, and at least one of the above. The optical component is provided with a flow device for circulating the cooling liquid, and the flow velocity of the cooling liquid flowing through the light emitting side of the at least one optical component is such that the cooling liquid flows through the light incident side of the at least one optical component. It is characterized in that it is smaller than the flow velocity of the cooling liquid.

In the above aspect, the optical modulator and the first polarizing element are housed in the housing, and the flow velocity of the cooling liquid flowing through the light emitting side of the first polarizing element is the light of the first polarizing element. The flow velocity of the cooling liquid flowing through the light emitting side of the light modulator, which is smaller than the flow velocity of the cooling liquid flowing through the incident side, is larger than the flow velocity of the cooling liquid flowing through the light incident side of the light modulator. It is preferable that the flow velocity of the cooling liquid flowing through the light incident side of the first polarizing element is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the light modulator.

In the above aspect, the flow velocity of the cooling liquid, which is housed in the housing and includes the second polarizing element arranged on the light incident side of the light modulator and flows through the light emitting side of the second polarizing element, is determined. It is preferably smaller than the flow velocity of the cooling liquid flowing on the light incident side of the second polarizing element.

In the above aspect, the optical modulator and the first polarizing element are housed in the housing, and the flow velocity of the cooling liquid flowing between the optical modulator and the first polarizing element is the second. It is preferably smaller than the flow velocity of the cooling liquid flowing between the polarizing element and the light modulator.

In the above aspect, the light modulator is a red light modulator that is incident with red light among the light emitted from the light source and modulates the incident red light, and the light emitted from the light source. Of these, a green light modulator that is incident with green light and modulates the incident green light, and a blue light that is incident with blue light among the light emitted from the light source and modulates the incident blue light. The first polarizing element includes a modulator, and the first polarizing element for red is arranged on the light emitting side of the first light emitting element for red and the first polarizing element for red arranged on the light emitting side of the light emitting device for red. The first polarizing element for green and the first polarizing element for blue arranged on the light emitting side of the blue light modulator are included, and the red light modulator, the green light modulator, and the blue light modulator are included. The light modulator, the red first polarizing element, the green first polarizing element, and the blue first polarizing element are housed in the housing and circulate on the light emitting side of the red light modulator. The flow velocity of the cooling liquid is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the green light modulator and the flow velocity of the cooling liquid flowing through the light emitting side of the blue light modulator. The flow velocity of the cooling liquid flowing through the light incident side of the red light modulator is the flow velocity of the cooling liquid flowing through the light incident side of the green light modulator and the light of the blue light modulator. The flow velocity of the cooling liquid which is smaller than the flow velocity of the cooling liquid flowing on the incident side and flows through the light emitting side of the first red polarizing element is the flow velocity of the cooling liquid flowing through the light emitting side of the first polarizing element for green. The flow velocity of the cooling liquid and the flow velocity of the cooling liquid flowing through the light incident side of the first polarizing element for red are smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the first polarizing element for blue. It is preferable that the flow velocity of the cooling liquid flowing through the light incident side of the green first polarizing element and the flow velocity of the cooling liquid flowing through the light incident side of the blue first polarizing element are smaller.

In the above aspect, the flow velocity of the cooling liquid flowing through the light emitting side of the blue light modulator is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the green light modulator, and the blue is used. The flow velocity of the cooling liquid flowing through the light incident side of the light modulator is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the green light modulator, and the light emitting side of the blue first polarizing element. The flow velocity of the cooling liquid flowing through is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the green first polarizing element, and the cooling liquid flowing through the light incident side of the blue first polarizing element. The flow velocity of the first polarizing element for green is preferably smaller than the flow velocity of the cooling liquid flowing on the light incident side of the first polarizing element for green.

The schematic diagram which shows the structure of the projector which concerns on 1st Embodiment. The schematic diagram which shows the cooling device in 1st Embodiment, and the image forming part arranged in the housing of the cooling device. FIG. 6 is a schematic diagram showing the flow velocity of the cooling liquid flowing along each optical component of the red image forming portion in the first embodiment by the size of an arrow indicating the flow direction of the cooling liquid. The schematic diagram which shows the cooling device provided in the projector in 2nd Embodiment. FIG. 6 is a schematic diagram showing the flow velocity of the cooling liquid flowing along each optical component of the red image forming portion in the second embodiment by the size of an arrow indicating the flow direction of the cooling liquid.

[First Embodiment]
Hereinafter, the first embodiment of the present invention will be described with reference to the drawings.
[Outline configuration of projector]
FIG. 1 is a schematic view showing the configuration of the projector 1 according to the present embodiment.
The projector 1 according to the present embodiment modulates the light emitted from the light source 41 provided inside to form an image according to the image information, and magnifies and projects the formed image onto a projected surface such as a screen. It is a projection type display device.
As shown in FIG. 1, the projector 1 includes an exterior housing 2 that constitutes the exterior of the projector 1, an image projection device 4 and a cooling device 5A housed in the exterior housing 2. Further, although not shown, the projector 1 includes a control device for controlling the operation of the projector 1 and a power supply device for supplying electric power to electronic components included in the projector 1.
Hereinafter, the configuration of the projector 1 will be described in detail.

[Outer housing configuration]
The outer housing 2 is formed in a substantially rectangular parallelepiped shape. The exterior housing 2 has a front portion 23, a back portion 24, a left side surface portion 25, and a right side surface portion 26, and although not shown, a top surface portion connecting one end of each surface portion 23 to 26 and each surface portion 23 to 26 It has a bottom surface portion for connecting the other end of the. The bottom surface has a plurality of legs that come into contact with the installation surface on which the projector 1 is installed.
The front portion 23 has an opening 231 that exposes a part of the projection optical device 46 described later.

[Configuration of image projection device]
The image projection device 4 projects an image according to the image information input from the control device. The image projection device 4 includes a light source 41, a homogenization device 42, a color separation device 43, a relay device 44, an image forming device 45, a projection optical device 46, and a housing 47 for optical components.

The light source 41 emits illumination light that illuminates the image forming apparatus 45 to the homogenizing apparatus 42. For example, the light source 41 includes a solid-state light source such as LD (Laser Diode) that emits blue light that is excitation light, and a part of blue light among the blue light emitted from the solid-state light source, including green light and red light. It has a wavelength conversion element that converts wavelength into fluorescence which is yellow light. The light source 41 may have a light source lamp such as an ultra-high pressure mercury lamp, and emits red light, green light, and blue light by another solid light source such as an LD or LED (Light Emitting Diode). It may be.

The homogenizing device 42 equalizes the illuminance of the luminous flux emitted from the light source 41, and illuminates the image forming apparatus 45 substantially uniformly with the luminous flux emitted from the light source 41. The homogenizing device 42 includes a first lens array 421, a second lens array 422, a polarization conversion element 423, and a superimposing lens 424. The homogenizing device 42 may further include a dimming device that shields a part of the transmitted light beam to adjust the amount of transmitted light.

The color separating device 43 separates the red light LR, the green light LG, and the blue light LB from the luminous flux incident from the homogenizing device 42. The color separator 43 is separated into a dichroic mirror 431 that reflects red light LR and green light LG and transmits blue light LB, and a dichroic mirror 432 that transmits red light LR and reflects green light LG. It has a reflection mirror 433 that reflects the blue light LB toward the field lens 451B described later. The green light LG reflected by the dichroic mirror 432 is incident on the field lens 451G.
The relay device 44 guides the red light LR separated by the dichroic mirror 432 to the field lens 451R. The relay device 44 includes an incident side lens 441, a reflection mirror 442, a relay lens 443, and a reflection mirror 444. The image projection device 4 is configured to pass the red light LR through the relay device 44, but the present invention is not limited to this, and for example, the image projection device 4 may be configured to pass the blue light LB.

The image forming apparatus 45 includes field lenses 451R, 451G, 451B provided in the optical path of the red light LR, the optical path of the green light LG, and the optical path of the blue light LB, respectively, and an image forming unit 452.
The field lenses 451R, 451G, and 451B make the incident colored light telecentric.
The image forming unit 452 modulates the red light LR, the green light LG, and the blue light LB incident through the field lenses 451R, 451G, and 451B, and synthesizes the modulated color lights to form an image. The image forming unit 452 outputs the formed image to the projection optical device 46. The configuration of the image forming unit 452 will be described in detail later.

The projection optical device 46 magnifies and projects the image incident from the image forming unit 452 onto the projected surface. That is, the projection optical device 46 projects the light modulated by the light modulation devices 455R, 455G, and 455B described later of the image forming unit 452. The projection optical device 46 is configured as a set lens having a lens barrel and a plurality of lenses arranged in the lens barrel.

The optical component housing 47 holds the homogenizing device 42, the color separating device 43, the relay device 44, and the field lenses 451B, 451G, and 451R.
Here, the image projection device 4 is set with an illumination optical axis Ax, which is a design optical axis. The optical component housing 47 holds the devices 42 to 44 and the field lenses 451B, 451G, and 451R at predetermined positions on the illumination optical axis Ax. The housing 47 for optical components has a space S in which the image forming unit 452 and the housing 51 of the cooling device 5A are arranged at positions surrounded on three sides by the field lenses 451B, 451G, and 451R.
The light source 41 and the projection optical device 46 are arranged at predetermined positions on the illumination optical axis Ax.

In the following description, the direction from the back surface portion 24 to the front surface portion 23 is defined as the + Z direction. Further, the directions that intersect in the + Z direction and intersect with each other are defined as the + X direction and the + Y direction. Of the + X direction and the + Y direction, the + X direction is the direction from the left side surface portion 25 to the right side surface portion 26, and the + Y direction is the direction from the bottom surface portion to the top surface portion of the exterior housing 2. That is, when the projector 1 is viewed from the + Y direction, the + Z direction is the direction in which the projection optical device 46 projects an image. Although not shown, the opposite direction of the + X direction is the −X direction, the opposite direction of the + Y direction is the −Y direction, and the opposite direction of the + Z direction is the −Z direction.
In this embodiment, the + X direction, the + Y direction, and the + Z direction are defined as directions orthogonal to each other.

[Structure of image forming part]
FIG. 2 is a schematic view showing an image forming unit 452 arranged in the housing 51 of the cooling device 5A. In other words, FIG. 2 is a schematic view of the cross section of the image forming portion 452 and the housing 51 along the XZ plane as viewed from the + Y direction.
As shown in FIG. 2, the image forming unit 452 includes a red image forming unit 453R, a green image forming unit 453G, a blue image forming unit 453B, and a color synthesizing device 458. Each of the red image forming unit 453R, the green image forming unit 453G, and the blue image forming unit 453B modulates the light emitted from the light source 21.

[Structure of red image forming part]
The red image forming unit 453R modulates the red light LR that has passed through the field lens 451R to form a red image. The red image forming unit 453R includes an incident side polarizing element 454R, an optical modulator 455R, a viewing angle compensating element 456R, and an outgoing side polarizing element 457R. That is, the red image forming unit 453R is a liquid crystal light bulb for red light LR.

The incident-side polarizing element 454R is a polarizing element located on the light incident side of the light modulator 455R, and corresponds to a second polarizing element provided in the optical path of the red light LR.
The optical modulator 455R modulates the red light LR that has passed through the incident side polarizing element 454R. That is, the light modulation device 455R is a red light modulation device in which red light LR is incident from the light emitted from the light source 41 and the incident red light LR is modulated. In the present embodiment, the optical modulation device 455R is composed of a transmissive liquid crystal panel.
The viewing angle compensating element 456R is provided on the light emitting side of the optical modulation device 455R. More specifically, the viewing angle compensating element 456R is provided between the optical modulation device 455R and the emitting side polarizing element 457R. The viewing angle compensating element 456R is an optical position generated between normal light and abnormal light due to birefringence of liquid crystal molecules when light is incident at an angle with respect to the normal of the light incident surface of the optical modulator 455R. Compensate for phase differences.
The emitting side polarizing element 457R is a first polarizing element located on the light emitting side of the light modulator 455R, and corresponds to a red first polarizing element provided in the optical path of the red light LR. More specifically, the emitting side polarizing element 457R is provided between the viewing angle compensating element 456R and the light incident surface 458R of the color synthesizer 458.

[Structure of green image forming part]
The green image forming unit 453G modulates the green light LG that has passed through the field lens 451G to form a green image. The green image forming unit 453G includes an incident side polarizing element 454G, an optical modulator 455G, a viewing angle compensating element 456G, and an emitting side polarizing element 457G. That is, the green image forming unit 453G is a liquid crystal light bulb for green light LG.

The incident-side polarizing element 454G is a polarizing element located on the light incident side of the optical modulator 455G, and corresponds to a second polarizing element provided in the optical path of the green light LG.
The optical modulator 455G modulates the green light LG that has passed through the incident side polarizing element 454G. That is, the light modulation device 455G is a green light modulation device in which green light LG is incident among the light emitted from the light source 41 and modulates the incident green light LG. In the present embodiment, the optical modulation device 455G has the same configuration as the optical modulation device 455R.
The viewing angle compensating element 456G is provided between the optical modulation device 455G and the emitting side polarizing element 457G. The viewing angle compensating element 456G functions in the same manner as the viewing angle compensating element 456R.
The emitting side polarizing element 457G is a first polarizing element located on the light emitting side of the light modulator 455G, and corresponds to a green first polarizing element provided in the optical path of the green light LG. More specifically, the emitting side polarizing element 457G is provided between the viewing angle compensating element 456G and the light incident surface 458G of the color synthesizer 458.

[Structure of blue image forming part]
The blue image forming unit 453B modulates the blue light LB that has passed through the field lens 451B to form a blue image. The blue image forming unit 453B includes an incident side polarizing element 454B, an optical modulator 455B, a viewing angle compensating element 456B, and an outgoing side polarizing element 457B. That is, the blue image forming unit 453B is a liquid crystal light bulb for blue light LB.

The incident-side polarizing element 454B is a polarizing element located on the light incident side of the light modulator 455B, and corresponds to a second polarizing element provided in the optical path of the blue light LB.
The light modulator 455B modulates the blue light LB that has passed through the incident side polarizing element 454B. That is, the light modulation device 455B is a blue light modulation device in which blue light LB is incident from the light emitted from the light source 41 and the incident blue light LB is modulated. In the present embodiment, the optical modulation device 455B has the same configuration as the optical modulation device 455R.
The viewing angle compensating element 456B is provided between the optical modulation device 455B and the emitting side polarizing element 457B. The viewing angle compensating element 456B functions in the same manner as the viewing angle compensating element 456R.
The emitting side polarizing element 457B is a first polarizing element located on the light emitting side of the light modulator 455B, and corresponds to a blue first polarizing element provided in the optical path of the blue light LB. More specifically, the emitting side polarizing element 457B is provided between the viewing angle compensating element 456B and the light incident surface 458B of the color synthesizer 458.

[Configuration of color synthesizer]
The color synthesizer 458 synthesizes the color light LR, LG, and LB emitted from the image forming units 453R, 453G, and 453B, and emits the combined color light to the projection optical device 46. The color light synthesized by the color synthesizer 458 forms an image projected by the projection optical device 46. In the present embodiment, the color synthesizer 458 is composed of a cross-dichroic prism having a substantially rectangular parallelepiped shape.
The color synthesizer 458 projects an image with a light incident surface 458R on which red light LR is incident, a light incident surface 458G on which green light LG is incident, and a light incident surface 458B on which blue light LB is incident. It has a light emitting surface 458E that emits light toward 46.
A light modulation device 455R, a viewing angle compensating element 456R, and an emitting side polarizing element 457R are held on the light incident surface 458R by a holding member (not shown). The same applies to the light incident surfaces 458G and 458B.

[Cooling device configuration]
The cooling device 5A cools the image forming unit 452, which is one of the cooling targets in the projector 1. The cooling device 5A has a housing 51 arranged in the space S as shown in FIGS. 1 and 2, and also has a distribution device 52 as shown in FIG.

[Case configuration]
As shown in FIG. 2, the housing 51 is a substantially rectangular parallelepiped-shaped sealed housing in which the image forming portion 452 is arranged inside and the cooling liquid is filled inside. Therefore, the image forming portion 452 arranged inside the housing 51 is immersed in the cooling liquid enclosed in the housing 51. That is, the housing 51 includes the optical components of the incident side polarizing elements 454R, 454G, 454B, the optical modulators 455R, 455G, 455B, the viewing angle compensating elements 456R, 456G, 456B, and the emitting side polarizing elements 457R, 457G, 457B. It is a housing that houses and contains a cooling liquid inside.
The closed housing also includes a simple closed structure within a range in which the cooling liquid is prevented from leaking to the outside of the housing 51. For example, the housing 51 may have a structure in which a part of the housing 51 is detachably attached via packing or the like.
As the cooling liquid, an inert liquid that does not affect the operation of the optical modulators 455R, 455G, and 455B, which are driven by supplying power and image information, can be used. The inert liquid is preferably a fluorine-based inert liquid, and for example, Fluorinert (trademark of 3M) or NOVEC (registered trademark of 3M) can be adopted.

The housing 51 has openings 511R, 511G, 511B, and 511E on different side surfaces.
A translucent member 512R is fitted in the opening 511R located on the side surface portion in the + X direction. The red light LR that has passed through the field lens 451R is incident on the incident side polarizing element 454R in the −X direction via the translucent member 512R.
A translucent member 512G is fitted in the opening 511G located on the side surface portion in the −Z direction. The green light LG that has passed through the field lens 451G is incident on the incident side polarizing element 454G in the + Z direction via the translucent member 512G.
A translucent member 512B is fitted in the opening 511B located on the side surface portion in the −X direction. The blue light LB that has passed through the field lens 451B is incident on the incident side polarizing element 454B in the + X direction via the translucent member 512B.
A translucent member 512E is fitted in the opening 511E located on the side surface portion in the + Z direction. The light emitted from the light emitting surface 458E of the color synthesizer 458 is incident on the projection optical device 46 in the + Z direction via the translucent member 512E.

[Distribution device configuration]
At least one distribution device 52 is provided in the housing 51. The circulation device 52 stirs the cooling liquid in the housing 51, and among the image forming portions 452, the incident side polarizing elements 454R, 454G, 454B, the optical modulators 455R, 455G, 455B, and the viewing angle compensating elements 456R, 456G, 456B. And the cooling liquid is circulated to each optical component of the emitting side polarizing elements 457R, 457G, and 457B. In the present embodiment, the distribution device 52 is provided in a dead space in a substantially square housing 51.
In this embodiment, four distribution devices 52 are provided in the housing 51. Specifically, the distribution device 52 includes distribution devices 52A, 52B, 52C, and 52D provided in the housing 51, respectively.

The distribution device 52A is provided in the corners of the + X direction and the + Z direction in the housing 51, and the distribution device 52B is provided in the corners of the + X direction and the −Z direction in the housing 51. The distribution device 52C is provided in the corners of the −X direction and the + Z direction in the housing 51, and the distribution device 52D is provided in the corners of the −X direction and the −Z direction in the housing 51.
In other words, the distribution devices 52A and 52B are arranged at positions that sandwich the red image forming unit 453R in the + Z direction, and the distribution devices 52C and 52D are arranged at positions that sandwich the blue image forming unit 453B in the + Z direction. Further, the distribution devices 52B and 52D are arranged at positions where the green image forming unit 453G is sandwiched in the + X direction. The number of distribution devices 52 and the arrangement of the distribution devices 52 can be changed as appropriate.

Each distribution device 52 has a motor (not shown), a shaft 521 rotated by the motor, and an impeller 522 provided on the outer periphery of the shaft 521.
The shaft 521 and the impeller 522 are provided inside the housing 51, and the motor is provided outside the housing 51. As a result, the heat of the motor is suppressed from being transferred to the cooling liquid in the housing 51.
As described above, each distribution device 52 is provided at a corner of the housing 51. For this reason, the shaft 521 and the impeller 522 of each distribution device 52 are provided at the corners where the light projected by the projection optical device 46 hardly passes when the inside of the housing 51 is viewed from the + Y direction.
The configuration of the distribution device 52 is not limited to the above.

When each distribution device 52 is driven, the cooling liquid in the housing 51 is agitated by the impeller 522 and circulates in the housing 51 mainly in the direction intersecting the + Y direction. As a result, the cooling liquid flows through the gaps between the optical components constituting the image forming unit 452.
For example, in the red image forming unit 453R, the cooling liquid is used between the inner surface of the housing 51 and the incident side polarizing element 454R, between the incident side polarizing element 454R and the optical modulator 455R, and the optical modulator 455R and the viewing angle compensation. Between the element 456R, between the viewing angle compensating element 456R and the emitting side polarizing element 457R, and between the emitting side polarizing element 457R and the light incident surface 458R in the + Z direction or the −Z direction when viewed from the + Y direction. To circulate. That is, the cooling liquid circulates on the light incident side of each optical component constituting the red image forming unit 453R, and also circulates on the light emitting side of each optical component. The cooling liquid flowing in this way and the optical component come into contact with each other, and the heat of the optical component is transferred to the cooling liquid, so that the incident side polarizing element 454R, the optical modulator 455R, and the viewing angle compensating element 456R, which are the optical components, respectively. And the emitting side polarizing element 457R is cooled.

In the blue image forming unit 453B, similarly to the red image forming unit 453R, the cooling liquid views the light incident side and the light emitting side of each optical component constituting the blue image forming unit 453B in the + Z direction when viewed from the + Y direction. Or it circulates in the -Z direction. As a result, the incident side polarizing element 454B, the optical modulation device 455B, the viewing angle compensating element 456B, and the outgoing side polarizing element 457B, which are optical components, are cooled, respectively.

Further, for example, in the green image forming unit 453G, the cooling liquid is between the inner surface of the housing 51 and the incident side polarizing element 454G, between the incident side polarizing element 454G and the optical modulator 455G, and the optical modulator 455G and the viewing angle. Between the compensating element 456G, between the viewing angle compensating element 456G and the emitting side polarizing element 457G, and between the emitting side polarizing element 457G and the light incident surface 458G, in the + X direction or -X direction when viewed from the + Y direction. It is distributed to. By transferring the heat of each optical component to the cooling liquid flowing in this way, the incident side polarizing element 454G, the optical modulator 455G, the viewing angle compensating element 456G, and the emitting side polarizing element 457G, which are the optical components, are cooled. To.

[Thickness of the cooling liquid flowing through the optical modulator and the polarizing element on the exit side]
As shown in FIG. 2, for the optical modulators 455R, 455G, 455B and the emitting side polarizing elements 457R, 457G, 457B, the thickness of the cooling liquid flowing on the light emitting side and the cooling liquid flowing on the light incident side. The liquid thickness of is the same. The liquid thickness referred to here is the thickness dimension of the flow path of the cooling liquid, and is the dimension along the traveling direction of the colored light passing through the optical component through which the cooling liquid flows.

For example, the liquid thickness of the cooling liquid flowing through the light emitting side of the optical modulator 455R matches the dimension between the optical modulator 455R and the viewing angle compensating element 456R, and flows through the light incident side of the optical modulator 455R. The thickness of the cooling liquid matches the dimension between the light modulator 455R and the incident side polarizing element 454R. Further, for example, the liquid thickness of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457R matches the dimension between the emitting side polarizing element 457R and the light incident surface 458R, and the light incident side of the emitting side polarizing element 457R. The thickness of the cooling liquid flowing through the light matches the dimension between the emitting side polarizing element 457R and the viewing angle compensating element 456R.
Then, in the red image forming unit 453R, the liquid thickness of the cooling liquid flowing through the light incident side of the light modulation device 455R and the liquid thickness of the cooling liquid flowing through the light emitting side of the light modulation device 455R are the same. The liquid thickness of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457R and the liquid thickness of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457R are the same.
Further, the thickness of the cooling liquid flowing through the light incident side of the photomodulator 455R, the liquid thickness of the cooling liquid flowing through the light emitting side of the photomodulator 455R, and the liquid thickness of the cooling liquid flowing through the light emitting side of the light emitting side polarizing element 457R are circulated. The liquid thickness of the cooling liquid and the liquid thickness of the cooling liquid flowing through the light emitting side of the light emitting side polarizing element 457R are the same.

Similarly, in the green image forming unit 453G, the liquid thickness of the cooling liquid flowing through the light incident side of the light modulator 455G, the liquid thickness of the cooling liquid flowing through the light emitting side of the light modulator 455G, and the emitting side polarizing element. The liquid thickness of the cooling liquid flowing through the light incident side of 457G and the liquid thickness of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457G are the same. The same applies to the blue image forming unit 453B.
However, not limited to this, the liquid thickness of the cooling liquid flowing through the light incident side and the light emitting side of the optical modulator and the liquid thickness of the cooling liquid flowing through the light incident side and the light emitting side of the emitting side polarizing element are , Does not have to be the same.

[Fluctuation of projected image]
The present inventor presents the flow velocity of the cooling liquid flowing on the light incident side of each optical component constituting the image forming unit 452, the flow velocity of the cooling liquid flowing on the light emitting side, and the projected image projected on the projected surface. We studied the relationship with fluctuations that can be visually recognized.
As a result, the present inventor has determined that the flow velocity of the cooling liquid flowing along the optical component on the light emitting side of the optical component constituting the image forming unit 452 is the cooling flow flowing along the optical component on the light incident side of the optical component. We found that it was more likely to affect the perception of fluctuations than the flow velocity of the liquid.
Then, the present inventor makes the flow velocity of the cooling liquid flowing along the optical component on the light emitting side of the optical component smaller than the flow velocity of the cooling liquid flowing along the optical component on the light incident side of the optical component. It was found that the fluctuations are less likely to be visually recognized in the projected image.

Based on such findings, the cooling device 5A includes the optical components constituting the red image forming unit 453R, the optical components constituting the green image forming unit 453G, and the optical components constituting the blue image forming unit 453B. Therefore, the cooling liquid is circulated so that the flow velocity of the cooling liquid flowing on the light emitting side is smaller than the flow velocity of the cooling liquid flowing on the light incident side.

FIG. 3 is a schematic view showing the flow velocity of the cooling liquid flowing along each optical component constituting the red image forming unit 453R by the size of an arrow indicating the flow direction of the cooling liquid. In FIG. 3, a large arrow indicates a high flow rate of the cooling liquid, and a small arrow indicates a low flow rate of the cooling liquid. In the example of FIG. 3, the cooling liquid that flows along each optical component of the red image forming unit 453R is assumed to flow in the −Z direction.
For example, as shown in FIG. 3, the flow velocity of the cooling liquid flowing along each optical component constituting the red image forming portion 453R decreases from the translucent member 512R toward the light incident surface 458R.

Of the cooling liquids flowing along the emitting side polarizing element 457R, the flow velocity of the cooling liquid flowing on the light emitting side of the emitting side polarizing element 457R is higher than the flow velocity of the cooling liquid flowing on the light incident side of the emitting side polarizing element 457R. Is also small. That is, the flow velocity of the cooling liquid flowing between the light incident surface 458R and the exit side polarizing element 457R is smaller than the flow velocity of the cooling liquid flowing between the exit side polarizing element 457R and the viewing angle compensating element 456R.

Of the cooling liquids flowing along the viewing angle compensating element 456R, the flow velocity of the cooling liquid flowing on the light emitting side of the viewing angle compensating element 456R is higher than the flow velocity of the cooling liquid flowing on the light incident side of the viewing angle compensating element 456R. Is also small. That is, the flow velocity of the cooling liquid flowing between the emitting side polarizing element 457R and the viewing angle compensating element 456R is smaller than the flow velocity of the cooling liquid flowing between the viewing angle compensating element 456R and the optical modulator 455R.
Of the cooling liquids flowing along the optical modulation device 455R, the flow velocity of the cooling liquid flowing on the light emitting side of the optical modulation device 455R is smaller than the flow velocity of the cooling liquid flowing on the light incident side of the optical modulation device 455R. That is, the flow velocity of the cooling liquid flowing between the viewing angle compensating element 456R and the optical modulation device 455R is smaller than the flow velocity of the cooling liquid flowing between the optical modulation device 455R and the incident side polarizing element 454R.

Of the cooling liquids flowing along the incident side polarizing element 454R, the flow velocity of the cooling liquid flowing on the light emitting side of the incident side polarizing element 454R is higher than the flow velocity of the cooling liquid flowing on the light incident side of the incident side polarizing element 454R. Is also small. That is, the flow velocity of the cooling liquid flowing between the optical modulator 455R and the incident side polarizing element 454R is the cooling flowing between the incident side polarizing element 454R and the translucent member 512R forming the inner surface of the housing 51. It is smaller than the flow velocity of the liquid.
Further, as described above, the flow velocity of the cooling liquid flowing along each optical component constituting the red image forming portion 453R decreases from the translucent member 512R toward the light incident surface 458R. That is, for example, the flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457R is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the light modulator 455R.

Although not shown, each optical component of the green image forming section 453G and each optical component of the blue image forming section 453B also have a cooling liquid flowing through the light emitting side as in the case of the red image forming section 453R. The flow velocity of the cooling liquid is smaller than the flow velocity of the cooling liquid flowing on the light incident side.

[Flow velocity of cooling liquid flowing through the same optical component in each image forming part]
In connection with the above-mentioned research, the present inventor is a cooling liquid flowing along the same optical component among the optical components constituting each of the red image forming section 453R, the green image forming section 453G, and the blue image forming section 453B. I studied the flow velocity of.
As a result, the flow velocity of the cooling liquid flowing along the optical component constituting the red image forming section 453R, the flow velocity of the cooling liquid flowing along the same optical component forming the green image forming section 453G, and the blue image forming. It has been found that the fluctuation is less likely to be visually recognized in the projected image by making it smaller than the flow velocity of the cooling liquid flowing along the same optical component constituting the portion 453B.
Further, the present inventor makes the flow velocity of the cooling liquid flowing along the optical component constituting the blue image forming portion 453B higher than the flow velocity of the cooling liquid flowing along the same optical component constituting the green image forming portion 453G. It has been found that the flow rate of the cooling liquid flowing through the optical component of the green image forming unit 453G can be increased by making the size smaller, so that the green image forming unit 453G, which tends to generate a large amount of heat generation, can be effectively cooled.
That is, the present inventor determines the flow velocity of the cooling liquid flowing along the optical component through which the red light LR passes for the same optical component in each of the red image forming section 453R, the green image forming section 453G, and the blue image forming section 453B. It was found that by making it the smallest and making the flow velocity of the cooling liquid flowing along the optical component through which the green light LG passes the highest, it becomes difficult to see the fluctuation in the projected image and the cooling efficiency can be improved. ..

Therefore, in the present embodiment, in the red image forming unit 453R, the green image forming unit 453G, and the blue image forming unit 453B, the flow velocity of the cooling liquid flowing along the same optical component is set to have the following relationship. Has been done.
The flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457R along the emitting side polarizing element 457R is the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457G along the emitting side polarizing element 457G. , And the light velocity of the light emitting side of the emitting side polarizing element 457B is smaller than the flow velocity of the cooling liquid flowing along the emitting side polarizing element 457B.
Preferably, the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457B along the emitting side polarizing element 457B is the cooling flowing through the light emitting side of the emitting side polarizing element 457G along the emitting side polarizing element 457G. It is smaller than the flow velocity of the liquid.
The same applies to the incident side polarizing elements 454R, 454G, and 454B.

The flow velocity of the cooling liquid flowing along the light incident side of the emitting side polarizing element 457R along the emitting side polarizing element 457R is the flow velocity of the cooling liquid flowing along the light incident side of the emitting side polarizing element 457G along the emitting side polarizing element 457G. , And the light incident side of the emitting side polarizing element 457B is smaller than the flow velocity of the cooling liquid flowing along the emitting side polarizing element 457B.
Preferably, the flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457B along the emitting side polarizing element 457B is the cooling flowing through the light incident side of the emitting side polarizing element 457G along the emitting side polarizing element 457G. It is smaller than the flow velocity of the liquid.
The same applies to the incident side polarizing elements 454R, 454G, and 454B.

The flow velocity of the cooling liquid flowing along the optical modulator 455R on the light emitting side of the optical modulator 455R is the flow velocity of the cooling liquid flowing along the optical modulator 455G on the light emitting side of the optical modulator 455G, and the light. The light emission side of the modulator 455B is smaller than the flow velocity of the cooling liquid flowing along the optical modulator 455B.
Preferably, the flow velocity of the cooling liquid flowing along the light emitting side of the light modulation device 455B along the light modulation device 455B is higher than the flow velocity of the cooling liquid flowing along the light emitting side of the light modulation device 455G. Is also small.

The flow velocity of the cooling liquid flowing along the light incident side of the light modulation device 455R along the light modulation device 455R is the flow velocity of the cooling liquid flowing along the light incident side of the light modulation device 455G along the light modulation device 455G, and the light. The light incident side of the modulator 455B is smaller than the flow velocity of the cooling liquid flowing along the optical modulator 455B.
Preferably, the flow velocity of the cooling liquid flowing along the light incident side of the light modulation device 455B along the light modulation device 455B is higher than the flow velocity of the cooling liquid flowing along the light incident side of the light modulation device 455G along the light modulation device 455G. Is also small.
As described above, by setting the flow velocity of the cooling liquid flowing along each optical component, it is possible to make it difficult for the fluctuation to be visually recognized in the projected image.

[Effect of the first embodiment]
The projector 1 according to the present embodiment described above has the following effects.
The projector 1 includes a light source 41, optical modulators 455R, 455G, 455B, a projection optical device 46, emission side polarizing elements 457R, 457G, 457B as a first polarizing element, and a cooling device 5A.
The optical modulators 455R, 455G, and 455B modulate the light emitted from the light source 41. The projection optical device 46 projects the light modulated by the optical modulators 455R, 455G, and 455B. The emitting side polarizing elements 457R, 457G, 457B are arranged on the light emitting side of the optical modulators 455R, 455G, 455B.

The cooling device 5A accommodates the optical modulators 455R, 455G, 455B and the emitting side polarizing elements 457R, 457G, 457B, and has a housing 51 in which a cooling liquid is sealed therein, and the optical modulators 455R, 455G, 455B and the emitting device 5A. The side polarizing elements 457R, 457G, and 457B are provided with distribution devices 52A to 52D for circulating the cooling liquid.
The flow velocity of the cooling liquid flowing through the light emitting side of the light modulation device 455R is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the light modulation device 455R. The same applies to the optical modulators 455G and 455B.
The flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457R is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457R. The same applies to the emitting side polarizing elements 457G and 457B.

According to such a configuration, the optical modulators 455R, 455G, 455B and the emitting side polarizing elements 457R, 457G, 457B, which generate heat when the projector 1 is driven, are immersed in the cooling liquid, so that these cooling targets are efficiently cooled. it can.
Further, the flow velocity of the cooling liquid flowing through the light emitting side and the light incident side of the optical modulators 455R, 455G, 455B, and the cooling liquid flowing through the light emitting side and the light incident side of the emitting side polarizing elements 457R, 457G, 457B. Since the flow velocity of the light is set as described above, it is possible to make it difficult to recognize the fluctuation in the projected image. Therefore, deterioration of the projected image can be suppressed.

The flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457R is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457R. The flow velocity of the cooling liquid flowing through the light emitting side of the light modulation device 455R is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the light modulation device 455R. The flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457R is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the optical modulator 455R. The same applies to the optical modulators 455G and 455B, and the same applies to the emitting side polarizing elements 457G and 457B.
According to such a configuration, the flow velocity of the cooling liquid flowing along the light modulation device 455R and the light emitting side polarizing element 457R is directed from the light emitting side of the light emitting side polarizing element 457R toward the light incident side of the light modulation device 455R. Can be lowered. Further, the flow velocity of the cooling liquid flowing along the light modulation device 455G and the light emitting side polarizing element 457G can be reduced from the light emitting side of the light emitting side polarizing element 457G toward the light incident side of the light modulation device 455G. Similarly, the flow velocity of the cooling liquid flowing along the light modulation device 455B and the light emitting side polarizing element 457B can be reduced from the light emitting side of the light emitting side polarizing element 457B toward the light incident side of the light modulation device 455B. .. Therefore, since the flow velocity on the light emitting side, which has a large influence on the fluctuation, can be maintained low, it is possible to make it difficult to recognize the fluctuation in the projected image.

The image forming unit 452 included in the projector 1 is housed in a housing 51 of the cooling device 5A, and is a second polarizing element arranged on the light incident side of the optical modulators 455R, 455G, 455B. , 454B. The flow velocity of the cooling liquid flowing through the light emitting side of the incident side polarizing element 454R is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the incident side polarizing element 454R. The same applies to the incident side polarizing elements 454G and 454B.
According to such a configuration, the incident side polarizing elements 454R, 454G, and 454B can be effectively cooled by the cooling liquid, and fluctuations can be made more difficult to recognize in the projected image.

The incident side polarizing element 454R, the optical modulation device 455R, and the outgoing side polarizing element 457R are housed in the housing 51. In the red image forming unit 453R, the flow velocity of the cooling liquid flowing between the optical modulator 455R and the emitting side polarizing element 457R is larger than the flow velocity of the cooling liquid flowing between the incident side polarizing element 454R and the optical modulator 455R. Is also small. The same applies to the incident-side polarizing element 454G, the optical modulation device 455G, and the outgoing-side polarizing element 457G, and the same applies to the incident-side polarizing element 454B, the optical modulation device 455B, and the outgoing-side polarizing element 457B.
According to such a configuration, the flow velocity of the cooling liquid flowing along the optical modulators 455R, 455G, 455B and the emitting side polarizing elements 457R, 457G, 457B can be reduced as it approaches the projection optical device 46. As a result, it is possible to make it more difficult to recognize fluctuations in the projected image.

The light modulation device 455R is a red light modulation device in which red light LR is incident from the light emitted from the light source 41 and the incident red light LR is modulated. The light modulation device 455G is a green light modulation device in which green light LG is incident among the light emitted from the light source 41 and modulates the incident green light LG. The light modulation device 455B is a blue light modulation device in which blue light LB is incident from the light emitted from the light source 41 and the incident blue light LB is modulated. The emitting side polarizing element 457R is a first polarizing element for red arranged on the light emitting side of the light modulation device 455R. The emitting side polarizing element 457G is a first green polarizing element arranged on the light emitting side of the light modulation device 455G. The emitting side polarizing element 457B is a first polarizing element for blue arranged on the light emitting side of the light modulation device 455B.

The flow velocity of the cooling liquid flowing through the light emitting side of the photomodulator 455R is the flow velocity of the cooling liquid flowing through the light emitting side of the photomodulator 455G and the flow velocity of the cooling liquid flowing through the light emitting side of the photomodulator 455B. Smaller than The flow velocity of the cooling liquid flowing through the light incident side of the photomodulator 455R is the flow velocity of the cooling liquid flowing through the light incident side of the photomodulator 455G and the flow velocity of the cooling liquid flowing through the light incident side of the photomodulator 455B. Smaller than The flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457R is the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457G and the cooling flowing through the light emitting side of the emitting side polarizing element 457B. It is smaller than the flow velocity of the liquid. The flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457R is the flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457G and the cooling flowing through the light incident side of the emitting side polarizing element 457B. It is smaller than the flow velocity of the liquid.
According to such a configuration, among the red light LR, the green light LG, and the blue light LB included in the projected image, it is possible to suppress the recognition of the fluctuation caused by the red light LR, which has a large influence on the fluctuation in the human eye. Therefore, it is possible to make it more difficult to recognize the fluctuation in the projected image.

The flow velocity of the cooling liquid flowing through the light emitting side of the light modulation device 455B is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the light modulation device 455G. The flow velocity of the cooling liquid flowing through the light incident side of the photomodulator 455B is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the photomodulator 455G. The flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457B is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457G. The flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457B is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457G.
According to such a configuration, the light modulator 455G and the emitting side polarizing element 457G on which the green light LG having a larger amount of light than the blue light LB is incident is more than the optical modulator 455B and the emitting side polarizing element 457B. The cooling liquid can be circulated. Therefore, the optical modulation device 455G, which tends to generate a larger amount of heat than the optical modulation device 455B, and the emission side polarizing element 457G, which tends to generate a larger amount of heat than the emission side polarizing element 457B, can be effectively cooled.

[Second Embodiment]
Next, the second embodiment of the present invention will be described.
The projector according to the present embodiment has the same configuration as the projector 1 according to the first embodiment. Here, in the projector 1, the flow direction of the cooling liquid flowing through each optical component arranged in the housing 51 was mainly in the direction of intersecting the + Y direction. On the other hand, in the projector according to the present embodiment, the distribution direction of the cooling liquid distributed to each optical component is mainly in the + Y direction. In this respect, the projector according to the present embodiment and the projector 1 according to the first embodiment are different. In the following description, parts that are the same as or substantially the same as those already described will be designated by the same reference numerals and description thereof will be omitted.

[Cooling device configuration]
FIG. 4 is a schematic view showing the configuration of the cooling device 5B included in the projector according to the present embodiment. In other words, FIG. 4 is a schematic view showing a cross section of the cooling device 5B along the XY plane.
The projector according to the present embodiment has the same configuration and function as the projector 1 except that it has a cooling device 5B instead of the cooling device 5A.
As shown in FIG. 4, the cooling device 5B includes a housing 51 in which an image forming portion 452 arranged inside is immersed by a cooling liquid sealed inside, a circulation device 53, and a cooling liquid in the housing 51. It has a supply pipe 54 for supplying the cooling liquid and a discharge pipe 55 for discharging the cooling liquid to the outside of the housing 51.

Of these, the supply pipe 54 is connected to the end in the −Y direction of the housing 51 so that the cooling liquid can flow inside and outside the housing 51, and the discharge pipe 55 is connected to the end of the housing 51 in the + Y direction. , The cooling liquid is connected so as to be able to flow inside and outside the housing 51.
The supply pipe 54 and the discharge pipe 55 are connected to a heat radiating portion (not shown). The heat radiating unit is a radiator that cools the cooling liquid by releasing the heat transferred from the cooling liquid circulating inside. That is, the cooling liquid in the housing 51 is circulated by the distribution device 53 in the circulation path composed of the housing 51, the discharge pipe 55, the heat radiating portion, and the supply pipe 54.

The distribution device 53 is provided in the housing 51 in the −Y direction with respect to the image forming unit 452. The distribution device 53 circulates the cooling liquid supplied from the supply pipe 54 in the + Y direction, and circulates the cooling liquid in the + Y direction along the image forming unit 452.
An example of a configuration in which the distribution device 53 includes a screw that rotates about a rotation axis along the + Y direction and a motor that rotates the screw.
Further, the distribution device 53 may be provided in the + Y direction with respect to the image forming unit 452.

FIG. 5 is a schematic view showing the flow velocity of the cooling liquid flowing along each optical component constituting the red image forming unit 453R by the size of an arrow indicating the flow direction of the cooling liquid. In FIG. 5, a large arrow indicates a high flow rate of the cooling liquid, and a small arrow indicates a low flow rate of the cooling liquid.
When the distribution device 53 is driven, the cooling liquid supplied into the housing 51 circulates in the + Y direction along each optical component of the image forming unit 452.
For example, in the red image forming unit 453R, as shown in FIG. 5, the cooling liquid is light between the translucent member 512R and the incident side polarizing element 454R, and between the incident side polarizing element 454R and the optical modulator 455R. Between the modulator 455R and the viewing angle compensating element 456R, between the viewing angle compensating element 456R and the emitting side polarizing element 457R, and between the emitting side polarizing element 457R and the light incident surface 458R of the color synthesizer 458. It circulates in the + Y direction.
The same applies to the green image forming unit 453G and the blue image forming unit 453B.

As in the case of the cooling device 5A, the flow velocity of the cooling liquid decreases from the translucent member 512R toward the light incident surface 458R. That is, among the flow rates of the cooling liquid flowing along the red image forming unit 453R, the flow rate of the cooling liquid flowing between the translucent member 512R and the incident side polarizing element 454R is the highest, and the flow rate of the cooling liquid flowing along the exit side polarizing element 457R is the highest. The flow velocity of the cooling liquid flowing between the light incident surface 458R is the lowest.
Then, among the cooling liquids flowing along the emitting side polarizing element 457R, the flow velocity of the cooling liquid flowing on the light emitting side of the emitting side polarizing element 457R is the flow velocity of the cooling liquid flowing on the light incident side of the emitting side polarizing element 457R. It is smaller than the flow velocity. Of the cooling liquids flowing along the optical modulator 455R, the flow velocity of the cooling liquid flowing on the light emitting side is smaller than the flow velocity of the cooling liquid flowing on the light incident side. Of the cooling liquids flowing along the incident side polarizing element 454R, the flow velocity of the cooling liquid flowing on the light emitting side of the incident side polarizing element 454R is higher than the flow velocity of the cooling liquid flowing on the light incident side of the incident side polarizing element 454R. Is also small.
The same applies to the green image forming unit 453G and the blue image forming unit 453B.

Also in this embodiment, the liquid thickness of the cooling liquid flowing through the light emitting side of the light modulation device 455R and the liquid thickness of the cooling liquid flowing through the light incident side of the light modulation device 455R are the same.
Further, the liquid thickness of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457R and the liquid thickness of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457R are the same.
Further, the liquid thickness of the cooling liquid flowing through the light emitting side of the optical modulator 455R, the liquid thickness of the cooling liquid flowing through the light incident side of the optical modulator 455R, and the light emitting side of the emitting side polarizing element 457R are circulated. The liquid thickness of the cooling liquid and the liquid thickness of the cooling liquid flowing on the light incident side of the light emitting side polarizing element 457R are the same.
The same applies to the green image forming unit 453G and the blue image forming unit 453B.

Further, the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457R is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing elements 457G and 457B, and the light emitting of the emitting side polarizing element 457B. The flow velocity of the cooling liquid flowing on the side is smaller than the flow velocity of the cooling liquid flowing on the light emitting side of the light emitting side polarizing element 457G. The same applies to the flow velocity of the cooling liquid flowing on the light incident side of the emitting side polarizing elements 457R, 457G, and 457B.
Further, the flow velocity of the cooling liquid flowing through the light emitting side of the optical modulator 455R is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the optical modulators 455G and 455B, and is flowing through the light emitting side of the optical modulator 455B. The flow velocity of the cooling liquid is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the light modulator 455G. The same applies to the flow velocity of the cooling liquid flowing on the light incident side of the optical modulators 455R, 455G, and 455B.

A projector 1 having such a cooling device 5B instead of the cooling device 5A can also achieve the same effect as the projector 1 having the cooling device 5A.
In the cooling device 5B, the supply pipe 54 is connected to the end in the −Y direction of the housing 51, the discharge pipe 55 is connected to the end in the + Y direction of the housing 51, and the cooling liquid in the housing 51 is , + Y direction. However, not limited to this, in the cooling device 5B, the supply pipe 54 is connected to the end in the + Y direction of the housing 51, the discharge pipe 55 is connected to the end in the −Y direction of the housing 51, and the distribution device 53 is connected. The cooling liquid in the housing 51 may be configured to circulate in the −Y direction by, for example, setting the flow direction of the cooling liquid in the −Y direction.

[Modification of Embodiment]
The present invention is not limited to each of the above embodiments, and modifications, improvements, and the like within the range in which the object of the present invention can be achieved are included in the present invention.
In the first embodiment, the cooling liquid flowing along the optical component of the image forming unit 452 is assumed to flow in the direction intersecting the + Y direction. For example, the cooling liquid flowing along each optical component of the red image forming unit 453R is assumed to flow in the + Z direction or the −Z direction. In the second embodiment, the cooling liquid flowing along the optical component of the image forming unit 452 is assumed to flow in the + Y direction. However, not limited to this, if the cooling liquid flows along the light incident surface or the light emitting surface of each optical component, the flow direction of the cooling liquid can be changed as appropriate. For example, in the projector shown in the second embodiment, the flow direction of the cooling liquid flowing along the optical component of the image forming unit 452 may be the −Y direction.

Further, the flow directions of the cooling liquid flowing along the optical components of the red image forming unit 453R, the green image forming unit 453G, and the blue image forming unit 453B may be different between the light incident side and the light emitting side. For example, the flow direction of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457R and the flow direction of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457R may be opposite to each other. Further, for example, the flow direction of the cooling liquid flowing through the light emitting side of the optical modulation device 455R and the flow direction of the cooling liquid flowing through the light incident side of the light modulation device 455R may be opposite to each other.

In each of the above embodiments, the flow velocity of the cooling liquid flowing through the light emitting side of the light modulation device 455R is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the light modulation device 455R. Further, the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457R is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457R. The same applies to the optical modulators 455G and 455B and the emitting side polarizing elements 457G and 457B. However, not limited to this, the flow velocity of the cooling liquid flowing through the light emitting side of one of the optical components of the optical modulator 455R and the emitting side polarizing element 457R is the cooling liquid flowing through the light incident side of one optical component. It should be smaller than the flow velocity of. The same applies to the optical modulation device 455G and the light emitting side polarizing element 457G, and the same applies to the light modulation device 455B and the light emitting side polarizing element 457B.

In each of the above embodiments, it is assumed that the image forming unit 452 including the optical modulation devices 455R, 455G, 455B and the emitting side polarizing elements 457R, 457G, 457B is housed in the housing 51. However, the present invention is not limited to this, and each of the optical modulators 455R, 455G, 455B and the emitting side polarizing elements 457R, 457G, 457B may not necessarily be housed in the housing 51. That is, at least one optical component of the optical modulator and the light emitting side polarizing element may be housed in the housing 51 so that the cooling liquid can flow between the light emitting side and the light incident side. At this time, when the optical modulation device is housed in the housing 51, at least one of the light modulation devices 455R, 455G, and 455B may be housed, and the light emitting side polarizing element is housed in the housing 51. In this case, at least one of the emitting side polarizing elements 457R, 457G, and 457B may be accommodated.

Further, at least one of the light emitting side and the light incident side of the emitting side polarizing element is configured so that the cooling liquid can flow, and at least one of the light emitting side and the light incident side of the light modulator corresponding to the emitting side polarizing element. The cooling liquid is configured to be flowable so that the flow velocity of the cooling liquid flowing along the emitting side polarizing element is smaller than the flow velocity of the cooling liquid flowing along the optical modulator corresponding to the emitting side polarizing element. It may be configured.
For example, while the cooling liquid can flow between the light emitting side of the emitting side polarizing element and the light incident side of the light modulator, the light incident side of the emitting side polarizing element and the light emitting side of the light modulator It may be configured so that the cooling liquid cannot flow. Even in this case, the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element may be smaller than the flow velocity of the cooling liquid flowing through the light incident side of the photomodulator.

Further, the incident side polarizing elements 454R, 454G, 454B and the viewing angle compensating elements 456R, 456G, 456B do not have to be housed in the housing 51 so that the cooling liquid can flow on the light emitting side and the light incident side. For example, when the incident side polarizing elements 454R, 454G, 454B are fitted in the openings 511R, 511G, 511B, at least one incident side polarizing element of the incident side polarizing elements 454R, 454G, 454B emits light. The cooling liquid may be provided in the housing 51 so that the cooling liquid can flow only on the emitting side, or may be provided in the housing 51 so that the cooling liquid can flow only on the light incident side.

In each of the above embodiments, the flow velocity of the cooling liquid flowing through each of the optical components of the red image forming unit 453R, the green image forming unit 453G, and the blue image forming unit 453B decreases from the color synthesizer 458 toward the light incident side. It became. For example, in each of the emitting side polarizing elements 457R, 457G, and 457B, the flow velocity of the cooling liquid flowing through the light emitting side is smaller than the flow velocity of the cooling liquid flowing through the light incident side. In each of the optical modulators 455R, 455G, and 455B, the flow velocity of the cooling liquid flowing on the light emitting side is smaller than the flow velocity of the cooling liquid flowing on the light incident side. Then, in each of the emitting side polarizing elements 457R, 457G, and 457B, the flow velocity of the cooling liquid flowing through the light incident side flows through the light emitting side of the corresponding light modulation device among the light modulators 455R, 455G, and 455B. It was assumed to be smaller than the flow velocity of the cooling liquid.
However, not limited to this, the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element, and the light emitting side of the light modulator If the flow velocity of the cooling liquid flowing through the light is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the photomodulator, the flow velocity of the cooling liquid flowing through the light incident side of the light emitting side polarizing element is the light of the light modulator. It may be larger than or the same as the flow velocity of the cooling liquid flowing on the exit side.

In each of the above embodiments, it is assumed that the incident side polarizing elements 454R, 454G, and 454B, which are the second polarizing elements, are housed in the housing 51. It is assumed that the flow velocity of the cooling liquid flowing through the light emitting side of the incident side polarizing elements 454R, 454G, 454B is smaller than the flow velocity of the cooling liquid flowing through the light incident side. However, the present invention is not limited to this, and the incident side polarizing elements 454R, 454G, and 454B may not be housed in the housing 51. That is, the incident side polarizing elements 454R, 454G, 454B do not have to be the objects to be cooled by the cooling devices 5A, 5B. The same applies to the viewing angle compensating elements 456R, 456G, and 456B.
Further, at least one of the incident side polarizing elements 454R, 454G, and 454B has a second polarizing element in which the flow velocity of the cooling liquid flowing on the light emitting side is smaller than the flow velocity of the cooling liquid flowing on the light incident side. It may be. The same applies to the viewing angle compensating elements 456R, 456G, and 456B.

In each of the above embodiments, in the red image forming unit 453R, the flow velocity of the cooling liquid flowing between the light modulation device 455R and the exit side polarizing element 457R flows between the incident side polarizing element 454R and the light modulation device 455R. It was assumed that it was smaller than the flow velocity of the cooling liquid to be used. However, not limited to this, the flow velocity of the cooling liquid flowing between the incident side polarizing element 454R and the light modulation device 455R can be appropriately changed, and the same applies to the green image forming unit 453G and the blue image forming unit 453B. There was.

In each of the above embodiments, the flow velocity of the cooling liquid flowing through the light emitting side of the light modulator 455R as the red light modulator is the cooling liquid flowing through the light emitting side of the light modulator 455G as the green light modulator. It is assumed that the flow velocity is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the light modulation device 455B as the light modulation device for blue. The flow velocity of the cooling liquid flowing through the light incident side of the photomodulator 455R is the flow velocity of the cooling liquid flowing through the light incident side of the photomodulator 455G and the flow velocity of the cooling liquid flowing through the light incident side of the photomodulator 455B. Was smaller than. The flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457R as the first polarizing element for red is the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457G as the first polarizing element for green. And, it is assumed that it is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457B as the first polarizing element for blue. The flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457R is the flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457G and the cooling flowing through the light incident side of the emitting side polarizing element 457B. It was assumed to be smaller than the flow velocity of the liquid.

Further, the flow velocity of the cooling liquid flowing through the light emitting side of the optical modulation device 455B is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the light modulation device 455G. The flow velocity of the cooling liquid flowing through the light incident side of the photomodulator 455B is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the photomodulator 455G. The flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457B is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the emitting side polarizing element 457G. The flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457B is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the emitting side polarizing element 457G.
However, not limited to this, the flow velocity of the cooling liquid flowing through each of the light emitting sides of the optical modulators 455R, 455G, and 455B and the flow velocity of the cooling liquid flowing through each light incident side can be changed as appropriate. .. For example, the flow velocity of the cooling liquid flowing through the light emitting side of each of the light modulators 455R, 455G, and 455B may be the same. Further, the flow velocity of the cooling liquid flowing through the light emitting side of another light modulation device different from the light modulation device 455R may be smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the remaining light modulation device. Further, the flow velocity of the cooling liquid flowing through the light incident side of another light modulation device different from the light modulation device 455R may be smaller than the flow velocity of the cooling liquid flowing through the light incident side of the remaining light modulation device.

In each of the above embodiments, the openings 511R, 511G, 511B of the housing 51 are closed by the translucent members 512R, 512G, 512B. However, not limited to this, the openings 511R, 511G, 511B may be blocked by the field lenses 451B, 451G, 451R, may be blocked by the incident side polarizing elements 454R, 454G, 454B, and may be photomodulated. It may be blocked by devices 455R, 455G, 455B.

Further, the housing 51 is supposed to accommodate the image forming unit 452. However, the present invention is not limited to this, and the cooling liquid can be circulated between the optical component constituting the red image forming section 453R, the optical component forming the green image forming section 453G, and the optical component forming the blue image forming section 453B. , Each may be housed in a different housing 51. That is, the housing in which the optical component of the red image forming portion 453R is housed and the cooling liquid is sealed inside and the optical component of the green image forming section 453G are housed and the cooling liquid is sealed in the inside. A housing and a housing containing the optical components of the blue image forming unit 453B and in which the cooling liquid is sealed may be provided individually.

In each of the above embodiments, the image forming unit 452 includes viewing angle compensating elements 456R, 456G, and 456B. However, not limited to this, the image forming unit 452 does not have to include the viewing angle compensating elements 456R, 456G, and 456B. In this case, the light incident side of the emitting side polarizing elements 457R, 457G, 457B as the first polarizing element may be regarded as the light emitting side of the light modulators 455R, 455G, 455B.

In each of the above embodiments, the projector includes three optical modulation devices 455B, 455G, and 455R, each of which is composed of a liquid crystal panel. However, the present invention is not limited to this, and the present invention can be applied to a projector provided with two or less or four or more optical modulation devices.
In each of the above embodiments, the image projection device 4 illustrates a configuration having the layout and optical components shown in FIG. However, the present invention is not limited to this, and an image projection device 4 having another layout and optical components may be adopted.

In each of the above embodiments, the optical modulation devices 455R, 455G, and 455B are configured to be composed of a transmissive liquid crystal panel in which the light incident surface and the light emitting surface are different. However, the present invention is not limited to this, and the optical modulation devices 455R, 455G, and 455B may have a structure having a reflective liquid crystal panel in which the light incident surface and the light emitting surface are the same. Further, if it is an optical modulation device capable of forming an image according to image information by modulating an incident light beam, a device using a micromirror, for example, a device using a DMD (Digital Micromirror Device) or the like, other than liquid crystal An optical modulator may be used.

1 ... Projector, 41 ... Light source, 452 ... Image forming unit, 453B ... Blue image forming unit, 453G ... Green image forming unit, 453R ... Red image forming unit, 454B, 454G, 454R ... Incident side polarizing element (second polarizing element) ), 455B ... Optical modulator (blue optical modulator), 455G ... Optical modulator (green optical modulator), 455R ... Optical modulator (red optical modulator), 456B, 456G, 456R ... Viewing angle compensation Element, 457B ... Exit side polarizing element (first polarizing element, first polarizing element for blue), 457G ... Exit side polarizing element (first polarizing element, first polarizing element for green), 457R ... Exit side polarizing element (first 1 polarizing element, first polarizing element for red), 458 ... color synthesizer, 458B, 458G, 458R ... light incident surface, 458E ... light emitting surface, 46 ... projection optical device, 5A, 5B ... cooling device, 51 ... Body, 511B, 511G, 511R ... Opening, 512B, 512G, 512R ... Translucent member, 52 (52A, 52B, 52C, 52D), 53 ... Distribution device.

Claims (6)

Light source and
An optical modulator that modulates the light emitted from the light source,
A projection optical device that projects light modulated by the light modulator,
A first polarizing element arranged on the light emitting side of the light modulator and
A housing containing at least one of the optical modulators of the optical modulator and the first polarizing element and having a cooling liquid sealed therein.
A distribution device for distributing the cooling liquid to at least one of the optical components is provided.
A projector characterized in that the flow velocity of the cooling liquid flowing through the light emitting side of the at least one optical component is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the at least one optical component. In the projector according to claim 1,
The optical modulator and the first polarizing element are housed in the housing.
The flow velocity of the cooling liquid flowing through the light emitting side of the first polarizing element is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the first polarizing element.
The flow velocity of the cooling liquid flowing through the light emitting side of the photomodulator is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the photomodulator.
A projector characterized in that the flow velocity of the cooling liquid flowing through the light incident side of the first polarizing element is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the light modulator. In the projector according to claim 1 or 2.
A second polarizing element housed in the housing and arranged on the light incident side of the photomodulator is provided.
A projector characterized in that the flow velocity of the cooling liquid flowing through the light emitting side of the second polarizing element is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the second polarizing element. In the projector according to claim 3,
The optical modulator and the first polarizing element are housed in the housing.
The flow velocity of the cooling liquid flowing between the optical modulator and the first polarizing element is smaller than the flow velocity of the cooling liquid flowing between the second polarizing element and the optical modulator. Projector. In the projector according to any one of claims 1 to 4.
The optical modulator is
Of the light emitted from the light source, red light is incident, and a red light modulator that modulates the incident red light, and
Of the light emitted from the light source, green light is incident, and a green light modulator that modulates the incident green light, and
Of the light emitted from the light source, blue light is incident, and includes a blue light modulator that modulates the incident blue light.
The first polarizing element is
The first polarizing element for red, which is arranged on the light emitting side of the light modulator for red,
The first polarizing element for green, which is arranged on the light emitting side of the light modulator for green,
The blue first polarizing element arranged on the light emitting side of the blue light modulator is included.
The red light modulator, the green optical modulator, the blue optical modulator, and the red first polarizing element, the green first polarizing element, and the blue first polarizing element are described in a housing. Contained in the body,
The flow velocity of the cooling liquid flowing through the light emitting side of the red light modulator is the flow velocity of the cooling liquid flowing through the light emitting side of the green light modulator and the light emission of the blue light modulator. Less than the flow velocity of the cooling liquid flowing on the side,
The flow velocity of the cooling liquid flowing through the light incident side of the red light modulator is the flow velocity of the cooling liquid flowing through the light incident side of the green light modulator and the light incident of the blue light modulator. Less than the flow velocity of the cooling liquid flowing on the side,
The flow velocity of the cooling liquid flowing through the light emitting side of the first polarizing element for red is the flow velocity of the cooling liquid flowing through the light emitting side of the first polarizing element for green and the first polarizing element for blue. It is smaller than the flow velocity of the cooling liquid flowing on the light emitting side of
The flow velocity of the cooling liquid flowing through the light incident side of the first polarizing element for red is the flow velocity of the cooling liquid flowing through the light incident side of the first polarizing element for green, and the first polarizing element for blue. A projector characterized in that it is smaller than the flow velocity of the cooling liquid flowing on the light incident side of the light incident side. In the projector according to claim 5,
The flow velocity of the cooling liquid flowing through the light emitting side of the blue light modulator is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the green light modulator.
The flow velocity of the cooling liquid flowing through the light incident side of the blue light modulator is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the green light modulator.
The flow velocity of the cooling liquid flowing through the light emitting side of the first polarizing element for blue is smaller than the flow velocity of the cooling liquid flowing through the light emitting side of the first polarizing element for green.
A projector characterized in that the flow velocity of the cooling liquid flowing through the light incident side of the first polarizing element for blue is smaller than the flow velocity of the cooling liquid flowing through the light incident side of the first polarizing element for green.

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