JP2003270716A - Rear projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rear projector which deals with upsizing of a transmission screen and can avert the physical deformation of the transmission screen and can stably hold displayed images even if the device is used for a long period of time. <P>SOLUTION: A receiving surface 52A1 touching the surface of a screen body and a supporting surface 52A2 touching the outer peripheral end of the screen body and holding the outer periphery of the screen body are formed in a screen housing section 52A in which the screen body is housed. The receiving surface 52A1 is formed to incline with the perpendicular direction of the supporting surface 52A2. While the screen body is held housed in the housing section 52A, the screen body comes to incline with the vertical direction of the supporting surface 52A2 and the projection point at which the centroid position of the screen body is projected perpendicularly to the supporting surface 52A2 is included within the receiving surface 52A1. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electro-optical device that modulates a light beam emitted from a light source to form an optical image according to image information, and an image forming including a projection optical system that magnifies and projects the optical image. Section, a box-shaped housing for accommodating the image forming section, and a screen that is exposed on either side of the box-shaped housing and projects the optical image formed by the image forming section. Relates to a rear projector equipped with.

[0002]

2. Description of the Related Art Conventionally, as a display device having a large screen, a rear projector for enlarging and projecting an image on the screen for display is known. Such a rear projector irradiates a transmissive liquid crystal panel with a light beam from a light source, magnifies image light modulated by the transmissive liquid crystal panel according to image information by a projection lens, and converts an optical path by a reflection mirror. And has a structure that leads to the back of the screen. Therefore, the image light passes through the screen, and the viewer sees the transmitted light. Such a transmissive screen has a layered structure in which a diffusion plate, a Fresnel lens, and a lenticular lens are stacked. The image light emitted from the projection lens enters the transmissive screen as divergent light while being enlarged and projected. The divergent light is prevented from being reflected by the diffusion plate and enters the Fresnel lens. This incident light is refracted by passing through the Fresnel lens, becomes a light beam parallel to the main optical axis from the projection lens, and enters the lenticular lens. The light beam incident on the lenticular lens diverges in the horizontal direction of the screen. The diverged light beam is refracted and scattered, passes through the screen as a light beam having an appropriate viewing angle, and an observer can observe the image light. Usually, the transmissive screen is formed by injection molding a synthetic resin such as plastic.

[0003]

In recent years, the use of home theaters and the like has promoted an increase in the size of rear projector screens. Since such a large-screen transmissive screen has a small thickness, the transmissive screen itself is liable to undergo physical deformation such as bending due to its own weight and warpage during manufacturing,
There is a problem that the screen buckles and bends with long-term use of the device, and the image displayed on the screen is distorted. Further, since each member of the transmissive screen composed of a plurality of members exhibits bending in different directions, there is a problem that a gap occurs between the members and the projected image is distorted.

An object of the present invention is to cope with an increase in size of a transmissive screen, avoid physical deformation of the transmissive screen and maintain a stable display image even when the device is used for a long period of time. It is to provide a rear projector that can do this.

[0005]

SUMMARY OF THE INVENTION A rear projector of the present invention is an electro-optical device that modulates a light beam emitted from a light source to form an optical image according to image information, and a projection optical system that magnifies and projects the optical image. An image forming unit including a system, a box-shaped housing for accommodating the image forming unit, and an optical image formed by the image forming unit exposed on one side surface of the box-shaped housing. And a screen for projecting the screen, wherein the housing includes a receiving surface formed along an outer peripheral edge of the screen to receive the screen in an out-of-plane direction, and the receiving surface has a vertical direction. When the screen is attached, the projection point obtained by vertically projecting the center of gravity of the screen onto the support surface is included in the receiving surface. The screen referred to here has a layered structure composed of a plurality of members such as a diffusion plate, a Fresnel sheet, a lenticular sheet, and a protection plate, or has a layered structure integrally composed of functions. Say

According to the present invention as described above, the housing is provided with the receiving surface, and the receiving surface is formed so as to be inclined in the vertical direction.
By preliminarily inclining the screen with respect to the vertical direction of the support surface and inclining the screen in one direction, physical deformation such as bending due to buckling of the screen can be limited. Further, by inclining, the directions of the centers of gravity of the plurality of screen members coincide with each other and the warp direction becomes constant, so that no gap is formed between the members. However, as described above, when the screen is tilted, physical deformation such as bending due to buckling can be avoided, but this tilt causes distortion in the screen in the tilt direction, that is, concave deformation. There is a new problem that it tends to happen. Here, when the screen is attached, since the projection point obtained by vertically projecting the center of gravity of the screen onto the supporting surface is included in the receiving surface, the screen is stably supported on the receiving surface, It is possible to prevent concave deformation due to heat of the screen or its own weight.

Therefore, the screen is inclined in advance with respect to the vertical direction of the supporting surface, and further, the center of gravity of the screen is arranged so as to be included in the receiving surface of the projection point vertically projected to the supporting surface. It is possible to prevent physical deformation due to heat or its own weight. With such a configuration, it is possible to prevent the distortion of the display image displayed on the screen in response to the increase in size of the screen, and to use it for a long period of time. Even an accurate display image can be held.

In the rear projector of the present invention, the receiving surface is provided on the front surface side of the screen, and the rear surface side of the screen is provided with a pressing member for pressing the screen from the rear surface side to the receiving surface side. Preferably. In such a configuration, the screen is securely fixed by providing the pressing member that supports the front surface side of the screen by the receiving surface and presses the back surface side of the screen from the back surface side to the receiving surface side. You can

In the rear projector of the present invention, it is preferable that an elastic member is interposed between the pressing member and the back surface of the screen. Normally, the inside of the housing that houses the screen has a structure that does not allow dust and dirt to enter, preventing dust and dirt from adhering to the light-incident surface of the screen, and eliminating pixels from the displayed image. I'm avoiding it. However, since the rear projector has a structure in which the constituent members are housed in the housing, it can be moved to any place, and when the rear projector moves, the screen vibrates and the screen and the housing move. Dust and fluff will occur due to the collision with.

Here, since the elastic member is interposed between the pressing member and the back surface of the screen, the vibration of the screen is suppressed even when the rear projector is moved, and the pressing member and It is possible to avoid collision with the screen and prevent dust and fluff from occurring. Therefore, since dust or the like does not adhere to the screen, the inside of the housing in which the screen is stored is always clean,
The image displayed on the screen can be kept clear.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. [1. Main Configuration of Rear Projector] FIG. 1 is a perspective view of a rear projector 1 according to the present invention as seen from the front.
FIG. 2 is a perspective view of the rear projector 1 as viewed from the rear. FIG. 3 is an exploded perspective view of the rear projector 1 seen from the rear, and specifically, the back cover 1 from FIG.
FIG. 4 is a view with 4 removed. FIG. 4 is an exploded perspective view of the rear projector 1 seen from below. FIG. 5 is a vertical cross-sectional view showing the rear projector 1.

Regarding the main configuration of the rear projector 1,
This will be described with reference to FIGS. The rear projector 1
As shown in FIGS. 1 to 5, a light beam emitted from a light source is modulated in accordance with image information to form an optical image, and the optical image is enlarged and projected on a screen. 10, a leg portion 20 provided on the lower surface side of the cabinet 10, an internal unit 40 as an image forming portion arranged in the cabinet 10, a reflection mirror 30 also arranged in the cabinet 10, and a cabinet 10 of the cabinet 10. Screen 50 exposed on the front surface
And is configured. These cabinet 10, internal unit 40, reflection mirror 30, and screen 5
The device main body is constituted by 0. In the present embodiment, for convenience, the left side when viewed from the front is the left and the right side when viewed from the front is the right.

The cabinet 10 is a housing made of synthetic resin for accommodating the internal unit 40 and the reflection mirror 30. As shown in FIG. 3, the cabinet 10 accommodates the internal unit 40, and the front side, the upper and lower sides and the left and right side surfaces. The lower cabinet 13 having a U-shaped vertical cross section that covers most of the sides, the back cover 14 that partially covers the rear side and the left and right side surfaces, and the upper cabinet 12 having a triangular cross section that is installed above the lower cabinet 13. And is configured. The dimension of the lower cabinet 13 in the left-right direction as a direction along the surface of the screen 50 is the upper cabinet 1.
2 is formed to be smaller than the dimension in the left-right direction as the direction along the surface of the screen 50. Further, the back cover 14 is configured to be detachable from the lower cabinet 13.

As shown in FIG. 4, the lower cabinet 13 includes a front surface portion 131, left and right side surface portions 132, and an upper surface portion 1.
33 and a lower surface portion 134. As shown in FIG.
In the lower cabinet 13, a center portion 131A that bulges toward the front side in accordance with the amount of projection of the projection lens that constitutes the internal unit 40 is provided substantially at the center of the front surface portion 131, and on the left and right sides of this center portion 131A. , Rectangular opening portions 131R and 131L having substantially the same dimensions are formed.
In these openings 131R and 131L, the woofer box 60 (60
R, 60L) are attached respectively. These woofer boxes 60R, 60L have openings 131R,
It can be attached to and detached from the front side of the 131L. Although not clearly shown in the drawing, the left opening 13
On the lower side of 1L, there are provided a connecting portion for connecting a computer and various equipment connecting terminals such as a video input terminal and an audio equipment connecting terminal.

Further, in the lower cabinet 13, as shown in FIG. 3, left and right side surface portions 132 are respectively formed with slit-shaped openings. The opening on the left is
An intake opening 132L for introducing cooling air into the inside,
The opening on the right side is an exhaust opening 132R for discharging the air introduced into the inside and cooling the inside.

The upper surface portion 133 is constructed to face a lower surface portion of the upper cabinet 12 which will be described later. Further, the lower surface portion 134 is arranged so as to abut a receiving surface of the leg portion 20 which will be described later.

The back cover 14 is, as shown in FIG.
It is configured by including a back surface portion 141 and left and right side surface portions 142. In the back cover 14, a second intake opening 141A for introducing cooling air is formed on the right side (the left side when viewed from the rear) of the back surface part 141. An air filter 143 is attached to the second intake opening 141A. The second intake opening 141A provided with the air filter 143 has a cover 144 that closes the opening 141A.
Is detachably attached. In addition, the back surface part 141
An opening for the inlet connector 145 is provided on the left side (the right side when viewed from the rear) of the second intake opening 141A in the above. Further, on the left side (the right side when viewed from the rear) of the back surface part 141, there are provided a connection part for connecting a computer and various device connection terminals such as a video input terminal and an audio device connection terminal. An interface board 80 is provided inside the.

The upper cabinet 12 is shown in FIGS.
Referring to FIG. 1, there is shown a housing having a triangular cross section for accommodating the reflection mirror 30, a substantially rectangular plate-shaped lower surface portion 15, and triangular plate-shaped left and right side surfaces erected from both ends of the lower surface portion 15. Is formed across the part 16 and the left and right side surfaces thereof,
A rear surface portion 17 that inclines toward the rear lower side and a front surface portion 18 that is formed in a substantially rectangular planar shape are provided. A rectangular opening 18A is formed in the planar front surface portion 18. A screen 50 that covers the opening 18A is attached to the front surface portion 18.

FIG. 6 is a vertical sectional view of the lower cabinet 13 side of the rear projector 1 and the legs 20 as seen from the front. Referring to FIGS. 3, 4 and 6, the leg portion 20 is a member made of synthetic resin that supports the apparatus body, and is a receiving surface 21 that abuts the entire lower surface portion 134 of the lower cabinet 13.
And a rib-shaped support portion 22 surrounding the back surface of the receiving surface 21 and having a predetermined height dimension. On the receiving surface 21, a recessed groove that is recessed by a dimension corresponding to the height dimension of the support portion 22 is formed at a position from the left side to the center in the center portion in the front-rear direction.

As shown in FIG. 4, when the rear projector 1 is installed on the upper surface of a floor or a desk, the rear surface of the supporting portion 22 is in contact with the upper surface of the floor or the like. On the inner side of the support portion 22, there is formed a lattice-shaped reinforcing rib 22A made of synthetic resin and having a predetermined height dimension. This reinforcing rib 22
By A, the rigidity of the leg portion 20 is enhanced and the leg portion 20 is prevented from being displaced from the upper surface such as the floor. However,
The reinforcing rib 22A is not formed on a part of the inside of the support portion 22, and a flat surface portion 22B extending from the left side to the center in the center portion in the front-rear direction is formed on the back surface side of the support portion 22. The flat surface portion 22B is a lower surface portion of the concave groove formed on the receiving surface 21.

As shown in FIG. 6, when the apparatus body is installed on the receiving surface 21 in which the concave groove is formed, it serves as a space extending in the left-right direction from the left side surface portion 132 of the lower cabinet 13 to the central portion. The third duct 93 is configured. However, the lower surface of the apparatus main body is not in contact with both end edges of the third duct 93, and the end edge portion near the left side surface portion 132 and the end edge portion of the substantially central portion are opened. One end of the second duct 92 is connected to the opening near the left side surface portion 132. The other end of the second duct 92 is connected to an intake opening 132L formed in the left side surface portion 132 via an air filter 135 which is a dustproof filter. Also, in the opening in the edge portion of this central portion,
One end of the fourth duct 94 is connected. The other end of the fourth duct 94 is arranged below the optical device that constitutes the main body of the device via an elastic member such as a sponge.

FIG. 7 is a front view of the rear projector 1 with the screen 50 removed. The reflection mirror 30 is a general reflection mirror formed in a substantially trapezoidal shape, and is attached inside the rear surface portion 17 of the upper cabinet 12 such that the long side of the trapezoid is the upper side. Upper cabinet 1
A mirror holder 31 for holding the reflection mirror 30 at a predetermined position is formed inside the rear surface 17 of the second mirror. With this mirror holding portion 31, the long side portion of the reflection mirror 30,
The short side portion and the oblique side portion are supported so that the reflection mirror 30 is not distorted.

[2. Configuration of Internal Unit] FIG. 8 is a perspective view of the internal unit as viewed from the rear. Internal unit 4
Reference numeral 0 is a device that forms a predetermined optical image according to the input image information and also amplifies the audio signal added to this image information and outputs audio and video.
The internal unit 40 includes an internal unit body 400, a support member 200 made of metal such as aluminum for supporting the internal unit body 400 in a predetermined posture, and the first power supply device 3.
01 and the second power supply device 302.

FIG. 9 is a perspective view of a supporting member constituting the internal unit as seen from above. The support member 200 is shown in FIG.
As shown in FIG.
A flat plate-shaped base member 201 arranged to face (FIG. 3)
A plate-like left-right position adjusting member 202 attached to the upper surface of the base member 201, and the left-right position adjusting member 2
The tilt adjusting member 203 is fixed to the upper surface of 02 and tilts downward to the rear side, and the rotational position adjusting member 204 is arranged to face the upper surface of the tilt adjusting member 203.

The base member 201 is a plate member that constitutes the lower surface side of the internal unit 40, and is configured to be able to move forward and backward with respect to the lower surface portion 134 of the lower cabinet 13. By moving the base member 201 back and forth, it is possible to take out the internal unit body 400 from the lower cabinet 13 to the rear side in a sliding manner like pulling out. Here, as shown in FIG. 8, a partition plate 205 that extends vertically and divides the lower cabinet 13 into two left and right spaces is formed at the right side (left side when viewed from the rear) of the base member 201. Has been done.

Returning to FIG. 9, the left / right position adjusting member 202
Has a plurality of loose holes 202A extending in the left-right direction. These loose holes 202A enable the left-right position adjusting member 202 to adjust the position in the left-right direction with respect to the base member 201. Note that the left-right position adjusting member 202 is adjusted in the left-right direction, and then screws are inserted into these loose holes 202A to make the base member 201
It is fixed with screws.

The tilt adjusting member 203 includes a plate-shaped tilt adjusting member main body 206 and legs 207 provided at four corners of the tilt adjusting member main body 206 so as to project downward. Each leg 207 is configured to be movable back and forth in the vertical direction. Further, in each leg portion 207, the tip end portion on the side opposite to the tilt adjusting member main body 206 has a left-right position adjusting member 202.
Is attached to. By moving these four legs 207 up and down, the left and right position adjusting member 20 is moved.
The posture of the tilt adjusting member main body 206 with respect to 2 can be adjusted.

The rotational position adjusting member 204 is the projection lens 4
By making the position X of the illumination optical axis of 6 substantially the rotation center, and urging the position away from the rotation center X in the front-back direction or the like, it is rotatable in the in-plane direction along the upper surface of the tilt adjusting member main body 206. It is configured. This rotational position adjusting member 20
An internal unit body 400 (FIG. 8) is attached to the upper surface of 4. From the above, the internal unit body 4
00 is a left-right position adjusting member 202 and an inclination adjusting member 203.
By the rotation position adjusting member 204, the base member 20
With respect to the upper surface of No. 1, the posture can be adjusted including the left-right direction, the tilt direction (tilt direction), and the in-plane rotation direction.

As shown in FIG. 8, the internal unit body 40
Reference numeral 0 includes a light source device 411 (not shown) arranged on the right side (left side when viewed from the rear), and extends from the light source device 411 to the left side and further to the front side in a substantially L-shaped optical unit 401 in plan view, A control board 402 is arranged so as to cover a part of the right side portion of the optical unit 401 and extends from the center to the left side (right side when viewed from the rear).

The control board 402 is a board provided with a control unit including a CPU and the like, and controls the drive of the optical device constituting the optical unit 401 according to the input image information. The periphery of the control board 402 is covered with a metallic shield member 403. This control board 4
The shield member 403 that covers 02 covers the optical unit 401 via a columnar member so that the rotation position adjusting member 2
It is attached to 04. The optical unit 401
The details of will be described later.

The first power supply device 301 is provided on the front side of the light source device 411 and on the left side of the partition plate 205. The first power supply block 303 and a lamp drive circuit (adjacent to the first power supply block 303). Ballast) 304. The first power supply block 303 passes through a power cable (not shown) connected to the inlet connector 145,
Electric power supplied from the outside is supplied to the lamp drive circuit 304, the control board 402, and the like. The lamp drive circuit 304 supplies electric power supplied from the first power supply block 303 to the light source lamps that form the optical unit 401.
It is electrically connected to this light source lamp. Such a lamp driving circuit 304 is wired, for example, on a substrate (not shown).

Further, the first power supply device 301 is covered with a metallic shield member 305 whose left and right sides are opened. The shield member 305 has a function of preventing leakage of electromagnetic noise. Furthermore, the first power supply device 3
In the opening on the center side of 01, the axial fan 5 for power supply
21 is attached. Thereby, the cooling air is blown in the extending direction of the first power supply device 301, that is, in the right direction from the central portion. In this case, the shield member 305 functions as a duct that guides the cooling air.

The second power supply device 302 is provided in the space on the right side of the partition plate 205, and the second power supply block 306.
And an audio signal amplification unit (amplifier) 307 that amplifies the input audio signal, and has a metal shield member 3 around the periphery.
It is covered with 08. The second power supply block 306 supplies power supplied from the outside to the audio signal amplification unit 307 through a power supply cable (not shown) connected to the inlet connector 145. The audio signal amplifier 307 is driven by the electric power supplied from the second power supply block 306 and amplifies the input audio signal, and is electrically connected to the speaker box and the woofer box described later, which are not shown in FIG. It is connected to the. Such an audio signal amplifier 307 is wired, for example, on a substrate (not shown).

[3. Configuration of Optical Unit] FIG. 10 is a perspective view showing the optical unit 401. FIG. 11 is a plan view schematically showing the optical unit 401. As shown in FIG. 11, the optical unit 401 optically processes a light beam emitted from a light source lamp that forms a light source device to form an optical image corresponding to image information, and magnifies and projects the optical image. The unit includes an integrator illumination optical system 41, a color separation optical system 42, a relay optical system 43, an optical device 44, a right-angle prism 48, and a projection lens 46 as a projection optical system.

The integrator illumination optical system 41 includes three liquid crystal panels 441 (liquid crystal panels 441R, 441G, 4 for each of red, green, and blue color lights, respectively) constituting the optical device 44.
41B) and an optical system for illuminating the image forming area substantially uniformly, and includes a light source device 411, a first lens array 412, a second lens array 413, a polarization conversion element 414, and a superimposing lens 415. Is equipped with.

The light source device 411 includes a light source lamp 416 as a radiation light source and a reflector 417, and reflects the radial rays emitted from the light source lamp 416 into the reflector 41.
It is reflected at 7 to be a parallel light beam, and this parallel light beam is emitted to the outside. A halogen lamp is used as the light source lamp 416. In addition to the halogen lamp, a metal halide lamp, a high pressure mercury lamp, or the like can be adopted. A parabolic mirror is used as the reflector 417. In addition,
Instead of a parabolic mirror, a combination of a collimating concave lens and an ellipsoidal mirror may be adopted.

The first lens array 412 has a structure in which small lenses having a substantially rectangular contour when viewed in the optical axis direction are arranged in a matrix. Each small lens splits the light flux emitted from the light source lamp 416 into a plurality of partial light fluxes. The contour shape of each small lens is the liquid crystal panel 44.
It is set so as to be substantially similar to the shape of the first image forming area. For example, if the aspect ratio (ratio of horizontal and vertical dimensions) of the image forming area of the liquid crystal panel 441 is 4: 3, the aspect ratio of each small lens is also set to 4: 3.

The second lens array 413 has substantially the same structure as the first lens array 412, and has a structure in which small lenses are arranged in a matrix. This second lens array 413, together with the superposing lens 415,
The image of each small lens of the lens array 412 is displayed on the liquid crystal panel 44.
1 has an image forming function.

The polarization conversion element 414 is arranged between the second lens array 413 and the superimposing lens 415 and is unitized with the second lens array 413. The polarization conversion element 414 as described above converts the light from the second lens array 413 into one type of polarized light, and thus the light utilization efficiency in the optical device 44 is improved.

Specifically, the polarization conversion element 414 outputs 1
Each of the partial lights converted into the polarized light of the type has a superposition lens 41.
Finally, it is almost superimposed on the liquid crystal panel 441 of the optical device 44. In the rear projector 1 using the liquid crystal panel 441 that modulates polarized light, only one kind of polarized light can be used, and therefore, almost half of the light from the light source lamp 416 that emits other kinds of randomly polarized light is not used. Therefore, by using the polarization conversion element 414, all the light fluxes emitted from the light source lamp 416 are converted into one type of polarized light, and the light utilization efficiency in the optical device 44 is improved. Note that such a polarization conversion element 414 is
For example, it is introduced in Japanese Patent Laid-Open No. 8-304739.

The color separation optical system 42 includes two dichroic mirrors 421 and 422 and a reflection mirror 423. The dichroic mirrors 421 and 422 divide a plurality of partial light beams emitted from the integrator illumination optical system 41 into red (R). ), Green (G), and blue (B).

The relay optical system 43 includes an incident side lens 431.
, Relay lens 433, and reflection mirrors 432, 434
And has a function of guiding the red light, which is the color light separated by the color separation optical system 42, to the liquid crystal panel 441R.

At this time, in the dichroic mirror 421 of the color separation optical system 42, the red light component and the green light component of the luminous flux emitted from the integrator illumination optical system 41 are transmitted and the blue light component is reflected. The blue light reflected by the dichroic mirror 421 is reflected by the reflection mirror 42.
The light is reflected at 3, and passes through the field lens 418 to reach the liquid crystal panel 441B for blue. The field lens 418 converts each partial light flux emitted from the second lens array 413 into a light flux parallel to the central axis (chief ray) thereof. The same applies to the field lens 418 provided on the light incident side of the other liquid crystal panels 441G and 441B.

Of the red light and the green light transmitted through the dichroic mirror 421, the green light is reflected by the dichroic mirror 422 and the field lens 41
8 to reach the liquid crystal panel 441G for green.
On the other hand, the red light passes through the dichroic mirror 422, passes through the relay optical system 43, and further passes through the field lens 4
The liquid crystal panel 441R for red light is reached through 18. The relay optical system 43 is used for red light because the optical path length of red light is longer than the optical path lengths of other color lights, so that the reduction of light utilization efficiency due to light divergence or the like is prevented. This is because. That is, the partial light flux that has entered the incident side lens 431 is directly transmitted to the field lens 418. Note that the relay optical system 43 is configured to pass red light of the three color lights, but is not limited to this, and may be configured to pass blue light, for example.

The optical device 44 modulates the incident light flux according to image information to form a color image,
Three incident side polarization plates 442 on which the respective color lights separated by the color separation optical system 42 are incident, and a liquid crystal panel 441R as a light modulation device arranged at the rear stage of each incidence side polarization plate 442,
441G and 441B and liquid crystal panels 441R and 441
G, 441B Ejection-side polarization plate 443 disposed after
And a cross dichroic prism 444 as a color combining optical system.

Liquid crystal panels 441R, 441G, 441B
For example, a polysilicon TFT is used as a switching element. In the optical device 44, the respective color lights separated by the color separation optical system 42 are supplied to the three liquid crystal panels 441R, 441G, 441B and the incident side polarization plate 44.
2 and the exit side polarization plate 443 form an optical image modulated according to image information.

The incident side polarization plate 442 is the color separation optical system 42.
Of the respective color lights separated in step 3, only polarized light in a certain direction is transmitted and other light flux is absorbed, and a polarizing film is attached to a substrate such as sapphire glass. The exit-side polarization plate 443 is also configured in substantially the same manner as the entrance-side polarization plate 442, and has a liquid crystal panel 441 (441R, 441G, 441).
Of the light beams emitted from B), only the polarized light in a predetermined direction is transmitted and the other light beams are absorbed. The incident side polarization plate 442 and the emission side polarization plate 443 are set such that the directions of their polarization axes are orthogonal to each other.

The cross dichroic prism 444 is
The color image is formed by combining the optical images emitted from the emission side polarization plate 443 and modulated for each color light.
The cross dichroic prism 444 is provided with a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light in a substantially X shape along the interfaces of the four rectangular prisms. Three color lights are combined by the multilayer film.

The liquid crystal panel 441, the exit side polarization plate 443 and the cross dichroic prism 444 described above.
Is configured as an optical device body 45 that is integrally unitized. The incident-side polarization plate 442 is attached by being slidably fitted into a groove portion (not shown) formed in the light guide 47.

Although not specifically shown, the optical device body 45 includes a cross dichroic prism 444, a metal pedestal for supporting the cross dichroic prism 444 from below, and the cross dichroic prism 44.
4 is attached to the light-incident end surface of the light flux No. 4 and has an exit-side polarization plate 443.
And a liquid crystal panel 441 (441R, 441G, 441B) held by four pin members attached to the light flux incident side of the holding plate. A gap with a predetermined interval is provided between the holding plate and the liquid crystal panel 441, and the cooling air flows through this gap.

The right-angled prism 48 is arranged on the light beam exit side of the cross dichroic prism 444 of the optical device 44, and the color image combined by the cross dichroic prism 444 is projected in the direction of the projection lens 46, that is, the color projected in the forward direction. The image is bent upward and reflected.

The projection lens 46 enlarges the color image reflected by the right-angle prism 48 and projects it on the reflection mirror 30. The projection lens 46 is supported by a support member that is screwed and fixed to the rotation position adjusting member 204. Further, as shown in FIG.
A box-shaped cover member 49A having an open upper side is provided around the projection side of. An opening is formed in the upper surface 133 of the lower cabinet 13 to secure the optical path of the projected optical image. The cover member 49A is in contact with the periphery of the opening via an elastic member to close the opening. The lower surface portion 15 of the upper cabinet 12 has the upper surface portion 133 of the lower cabinet 13.
An opening corresponding to the opening is provided.

Each of the optical systems 41 to 44, 48 described above
Is accommodated in a light guide 47 made of synthetic resin as a housing for optical components shown in FIG. The light guide 47 is not shown in FIG.
As shown in FIG.
18, 421-423, 431-434, 442 (Fig. 1
The lower light guide 471 is formed with a groove portion into which 1) is slidably fitted from above, and a lid-shaped upper light guide 472 that closes the upper opening side of the lower light guide 471.

As shown in FIG. 1, the screen 50 is a transmissive screen which projects the optical image enlarged by the projection lens of the optical unit 401 and reflected by the reflection mirror from the back surface. The screen 50 includes a screen body 51 and a screen cover 5 for housing the screen body 51 with the front side of the screen body 51 exposed.
2 and.

The screen main body 51 has a four-piece construction including a diffusion plate, a Fresnel sheet, a lenticular sheet, and a protective plate in order from the position close to the incident light, that is, from the back surface side.
The light flux emitted from the projection lens and reflected by the reflection mirror is diffused by a diffusion plate, then collimated by a Fresnel sheet, and diffused by optical beads constituting a lenticular sheet to obtain a display image.

Here, as shown in FIG. 2, speaker boxes 70 are attached to the left and right side surfaces 16 of the upper cabinet 12, respectively, and are constructed separately from the upper cabinet 12. The speaker box 70 is a box type that functions as a predetermined speaker. The front surface of the speaker box 70 and the front surface of the screen 50 are substantially flush with each other, and these surfaces are substantially parallel to the vertical direction. As described above, as shown in FIG. 1, the screen cover 52 is fixed to the upper cabinet 12 so as to cover the front surface portion 18 of the upper cabinet 12 and the front surface of the speaker box 70 in a state where the screen body 51 is housed. .

[4. Configuration of Internal Cooling Unit (Cooling Structure)] FIG. 12 is a plan view showing the rear projector 1. Figure 1
3 is a vertical sectional view taken along line XIII-XIII in FIG. Here, in the rear projector 1,
As shown in FIG. 3, an internal cooling unit 500 that cools each of these components 400, 200, 301, 302 that form the internal unit 40 and the inside of the cabinet 10 is provided. The internal cooling unit 500 is provided in the internal unit 40.
The entire inside of the lower cabinet 13 including is cooled.

As shown in FIGS. 12 and 13, the internal cooling section 500 is connected to the lower cabinet 13 through the intake opening 132L.
External cooling air is introduced into the lower cabinet 13
Cool each component 400, 200, 301, 302 in
The air after cooling is discharged to the outside through the exhaust opening 132R on the right side. That is, in the lower cabinet 13, a cooling flow path is formed along the front surface of the screen 50 to flow cooling air from the left side to the right side. The internal cooling unit 500 includes a control substrate cooling flow channel 511, an optical device cooling flow channel 512, a light source cooling flow channel 513, and a power supply cooling flow channel 51.
4 and.

In the internal cooling section 500, as shown in FIG. 12 or 13, a part of the external cooling air introduced from the intake opening 132L by the fans 522 and 523 is partly an axial fan for the control board. 522 is sucked, flows through the control board cooling flow path 511,
Cool 2. The remaining part of the cooling air is sucked by the axial fan 523 and the sirocco fan 524 for the optical device, and flows through the optical device cooling flow path 512 including the second to fourth ducts 92 to 94. , Optical device 4
Cool 4. These cooling air merges in the vicinity above the optical device 44.

Here, in the light source cooling flow path 513, the first duct 91 arranged in the space on the right side of the partition plate 205 and extending in the front-rear direction is used. As shown in FIG. 12, a part of the merged air is sucked by two sirocco fans 525 and 526 for cooling optical components, flows through a light source cooling flow path 513 in the light guide 47, and the polarization conversion element. And cooling the light source device, and then the first duct 9
1, and is discharged to the outside from the exhaust opening 132R.

On the other hand, the remaining part of the merged air is sucked by the axial fan 521 for power supply and flows through the power supply cooling flow path 514 to cool the first power supply device 301 and the second power supply device 302, The gas is discharged from the exhaust opening 132R to the outside. In this way, 2
One flow path is provided. Then, the air after cooling the light source device 411 does not come into contact with other parts,
The second power supply device 3 is directly discharged from the duct 91 to the outside.
It does not interfere with 02.

[5. Structure of Screen Main Body] FIG.
It is a top view which showed the screen main body 51 typically. The screen body 51 projects the divergent light (image light) projected from the optical unit 401 and reflected by the reflection mirror 30 as image light having an appropriate viewing angle. It has a layered structure in which the plate 51C, the Fresnel sheet 51A, the lenticular sheet 51B, and the protective plate 51D are integrally configured.

The Fresnel sheet 51A is the optical unit 4
Divergent light (image light) projected from the projection lens 46 of 01
Is incident on the lenticular sheet 51B as a light beam that is parallel to or converges with respect to the main optical axis of the projection lens 46. Specifically, this Fresnel sheet 51A
Is equipped with a lens section composed of a group of prisms arranged concentrically, and is capable of converging or converging the divergent light projected from the projection lens 46 with respect to the main optical axis of the projection lens 46. After passing through 51A, the light is incident on the lenticular sheet 51B to determine the horizontal and vertical viewing angles.

The lenticular sheet 51B spreads the light flux emitted from the Fresnel sheet 51A in the horizontal direction to expand the divergence in the horizontal direction. Generally, the horizontal viewing angle needs to be wider than the vertical viewing angle, and the lenticular sheet 51B includes a plurality of semi-cylindrical lens portions arranged in parallel on the image light emitting surface side.

The diffusing plate 51C is for eliminating reflection on the incident surface of the Fresnel sheet 51A, and the incident surface is formed into fine irregularities so that the incident light is reflected on the incident surface and re-reflected by the reflection mirror 30. This prevents the image from being projected again as a shifted image on the screen. The protection plate 51D is a portion exposed to the outside in the screen body, and includes the Fresnel sheet 51A and the lenticular sheet 51.
B and the diffuser plate 51C are prevented from being damaged or damaged by the influence of external force.

These Fresnel sheet 51A, lenticular sheet 51B, diffusion plate 51C, and protection plate 51D.
The screen body 51 composed of is made of synthetic resin such as plastic and is formed by injection molding or the like. Here, the diffusion plate 51C may be integrated by forming fine irregularities on the incident surface of the Fresnel sheet 51A.

[6. Holding structure of screen body] FIG.
[Fig. 3] is a view of the screen 50 as viewed from the back side. FIG.
FIG. 7 is a sectional view showing a holding structure in a lower portion of the screen 50. As shown in FIG. 15, the screen cover 52 is formed in a substantially rectangular frame shape, and has a screen housing portion 52A in which the screen body 51 is housed and a state in which the screen body 51 is housed in the screen housing portion 52A. The screen main body 51 includes a screen holding portion 52B that presses and fixes the back surface of the screen main body 51. The above-described speaker box housing portions are formed on both left and right sides of the screen cover 52.

As shown in FIG. 16, the screen storage portion 5
2A, the receiving surface 52A1 that contacts the surface of the screen body 51, and the outer peripheral end of the screen body 51,
Support surface 52A2 for holding the outer periphery of the screen body 51
Are formed and have a substantially L-shaped cross section. Here, the receiving surface 52A1 is formed to be inclined outward with respect to the vertical direction of the supporting surface 52A2.

In the holding structure in the upper portion of the screen 50, the receiving surface 52A1 is opposite to the above lower portion.
Is inclined inward with respect to the vertical direction of the support surface 52A2, and in the holding structure in the left and right portions of the screen 50, the receiving surface 52A1 is inclined from below to above with respect to the vertical surface of the support surface 52A2. Has been formed.

The screen holding portion 52B is formed in a Z-shape in cross section, and comprises a fixing portion 52B1 fixed to the screen cover 52 and a pressing portion 52B2 for pressing and fixing the screen body 51. The fixing portion 52B1 has a hole 52B3 for fixing to the screen cover 52.
When storing and holding the screen main body 51, a screw is inserted into the hole 52B3 and the hole 52B3 and the hole 52C formed in the screen cover 52 are fixed, so that the screen main body 51 has a screen storage portion. It is pressed and fixed to 52A. The screen body 5 is attached to the pressing portion 52B2.
The elastic member 52D is attached to the surface that abuts on the screen 1, so that the pressing portion 52B2 and the end surface of the screen body 51 do not directly collide when the screen body 51 is stored and held.

Here, when the screen body 51 is housed in the screen cover 52, the surface side of the screen body 51 contacts the receiving surface 52A1 and is inclined toward the surface side of the screen 50 with respect to the vertical direction of the supporting surface 52A2. Will be stored and held at an angle of. In such a tilted state of the screen body 51, a point obtained by vertically projecting the position of the center of gravity of the screen body 51 on the support surface 52A2 of the screen storage portion 52A is projected on the receiving surface 52A1 of the screen storage portion 52A. .

Normally, the screen body 51 is installed in parallel with the vertical direction of the support surface 52A2 of the screen housing portion 52A. In such a state, the screen body is projected by the image light projected from the optical unit 401. 51
The screen body 51 is in a state in which physical deformation such as bending due to buckling is likely to occur due to the heat generated in the screen or the weight of the screen body 51. The physical deformation such as the buckling of the screen body 51 due to the heat or the self-weight of the screen body 51 causes the screen body 51 to be inclined with respect to the vertical direction of the support surface 52A2 of the screen housing portion 52A, and the screen body 51 may be inclined. This can be avoided by the structure in which the front surface side of the above is held by the receiving surface 52A1 of the screen storage portion 52A.

Further, the distortion in the inclination direction of the screen body 51, which is caused when the screen body 51 is inclined, that is, the concave deformation can be avoided as follows. FIG. 17 is a schematic diagram for comparing the inclination of the screen body 51 and the projection point O2 of the center of gravity position O1 on the screen body 51. As shown in FIG. 17 (A), the center of gravity O1 of the screen body 51 is set to the supporting surface 52A of the screen housing portion 52A while the screen body 51 is inclined.
When the point O2 perpendicularly projected to 2 is away from the receiving surface 52A2, there is nothing to support the center of gravity O1 of the screen body 51, and the heat generated in the screen body 51 or the weight of the screen body 51 itself The screen body 51 is physically deformed, and for example, is deformed into a concave shape when viewed from the front of the screen 50.

On the other hand, as shown in FIG. 17B, in the same manner as described above, the center of gravity O1 of the screen main body 51 is set at the screen accommodating portion 52A while the screen main body 51 is inclined.
When the point O2 perpendicularly projected to the supporting surface 52A2 of the above is on the receiving surface 52A1, the center of gravity O1 of the screen body 51 is supported by the receiving surface 52A2, and the concave deformation of the screen body 51 as described above is performed. It can be avoided.

[7. Effects of Embodiment] According to the present embodiment as described above, there are the following effects. (1) The screen cover 52 is the screen storage portion 52.
Since the screen housing portion 52A is formed in the shape of a substantially rectangular frame having a cross section A and includes the receiving surface 52A1 and the supporting surface 52A2, the screen main body 51 can be reliably held. (2) Since the receiving surface 52A1 of the screen storage portion 52A is formed to be inclined with respect to the support surface 52A2, the screen main body 51 is stored in the support surface of the screen storage portion 52A. 52A2
Is inclined with respect to the vertical direction, and the front surface side of the screen body 51 is supported by the receiving surface 52A1. By tilting the screen body 51 in one direction, bending of the screen body 51 due to buckling etc. Physical deformation can be prevented.

(3) The screen body 51 is formed by inclining the screen body 51 with respect to the vertical direction of the support surface 52A2 of the screen housing portion 52A.
Fresnel sheet 51A, lenticular sheet 51B,
Since the directions of the centers of gravity of the diffusion plate 51C and the protection plate 51D coincide with each other and the warpage direction is constant, it is possible to avoid a gap from being formed between the members.

(4) When the screen body 51 is tilted with respect to the vertical direction of the support surface 52A2 of the screen housing 52A, the center of gravity O1 of the screen body 51 is projected vertically to the support surface 52A2. , Receiving surface 5
By being included in the surface of 2A2, the screen main body 51 is stably supported by the receiving surface 52A2, and it is possible to prevent the concave deformation of the screen main body 51 due to heat or its own weight.

Therefore, by tilting the screen main body 51 in advance with respect to the vertical direction of the support surface 52A2, physical deformation such as bending due to buckling of the screen main body 51 is prevented, and the center of gravity O1 of the screen main body 51 is prevented. Is arranged so as to be included in the receiving surface 52A2, which is a projection point O2 vertically projected onto the supporting surface 52A2, and thus it is possible to prevent the concave deformation of the screen main body 51. The display image displayed on the screen body 51 can be prevented from being distorted or the like in response to the increase in size, and an accurate display image can be held even during long-term use.

(5) The screen body 51 has a screen holding portion 52 formed separately from the screen cover 52.
By being pressed and fixed by B, the screen body 51 can be securely held and fixed to the screen cover 52.

(6) The screen accommodating portion 52A has a receiving surface 52A1 that abuts on the light beam exit end surface of the screen body 51.
And the screen holding portion 52B for pressing and fixing the screen body 51, and the elastic member 52D is interposed at the end surface of the pressing portion 52B2 of the screen holding portion 52B that abuts the screen body 51, thereby moving the rear projector 1. Even if it does, the screen body 51
The vibration of the screen holding part 52B and the screen body 51 is prevented by the elastic member 52D interposed between the pressing part 52B2 and the screen body 51, and the generation of dust and fluff is prevented. can do. Therefore, since dust or the like does not adhere to the screen body 51, the inside of the upper cabinet 12 in which the screen body 51 is housed is always kept clean, and the screen body 5 is kept clean.
The image displayed in No. 1 can be kept clear.

(7) Since the screen body 51 is provided with the protective plate 51D on the end surface exposed to the outside, scratches or damage due to external force on the screen body 51 are avoided, and the image displayed on the screen is displayed. It can be held clearly. (8) Since the screen body 51 is provided with the protective plate 51D, the screen body 51 can be reinforced and the bending or the like of the screen body 51 due to heat or its own weight can be mitigated.

[8. Modification of Embodiment] The present invention is not limited to the above-described embodiment, and includes modifications as described below. For example, in the above-described embodiment, the screen main body 51 has a layered structure including four layers of the Fresnel sheet 51A, the lenticular sheet 51B, the diffusion plate 51C, and the protection plate 51D.
The configuration is not limited to this, and may have other configurations, or the order of these layers may be changed.

Further, in the above structure, a diffusing material may be mixed in the lenticular sheet 51B so that the lenticular sheet and the diffusing plate are integrated. Also,
In the above embodiment, only the example of the rear projector using three light modulation devices is given, but the present invention is a rear projector using only one light modulation device, a rear projector using two light modulation devices, Alternatively, it can be applied to a rear projector using four or more light modulators.

Further, in each of the above-mentioned embodiments, the liquid crystal panel is used as the light modulating device, but a light modulating device other than liquid crystal such as a device using a micromirror may be used. In this case, the polarizing plates on the entrance and exit sides can be omitted. Further, in the above-described embodiment, the transmissive light modulator having the different light incident surface and the light exit surface is used. However, the reflective light modulator having the same light incident surface and the light exit surface is used. Good.

[0085]

According to the rear projector of the present invention, it is possible to cope with an increase in the size of a transmissive screen and avoid physical deformation of the transmissive screen even when the apparatus is used for a long period of time, and display images are displayed. Has an effect that can be stably held.

[Brief description of drawings]

FIG. 1 is a perspective view of a rear projector according to the present embodiment as seen from the front.

FIG. 2 is a perspective view of the rear projector according to the exemplary embodiment seen from the rear.

FIG. 3 is an exploded perspective view of the rear projector according to the exemplary embodiment as viewed from the rear, specifically, a view in which the back cover is removed from FIG. 2.

FIG. 4 is an exploded perspective view of the rear projector according to the exemplary embodiment seen from below.

FIG. 5 is a vertical cross-sectional view showing the rear projector according to the embodiment.

FIG. 6 is a vertical cross-sectional view of the lower cabinet and legs according to the embodiment as seen from the front.

FIG. 7 is a front view of the rear projector according to the exemplary embodiment with a screen removed.

FIG. 8 is a perspective view of the internal unit according to the embodiment when viewed from the rear.

FIG. 9 is a perspective view of the support member according to the above embodiment as seen from above.

FIG. 10 is a perspective view showing an optical unit according to the embodiment.

FIG. 11 is a plan view schematically showing the optical unit according to the embodiment.

FIG. 12 is a plan view showing the rear projector according to the embodiment.

13 is a vertical sectional view taken along line XIII-XIII in FIG.

FIG. 14 is a plan view showing the structure of the screen body according to the embodiment.

FIG. 15 is a view of the screen according to the embodiment seen from the back surface.

FIG. 16 is a cross-sectional view showing a holding structure of the screen body according to the embodiment.

FIG. 17 is a diagram schematically showing a tilted state of the screen according to the embodiment.

[Explanation of symbols]

1 Rear Projector 10 Cabinet (Housing) 40 Internal Unit (Image Forming Unit) 46 Projection Lens (Projection Optical System) 411 Light Source Device (Light Source) 441, 441R, 441G, 441B Liquid Crystal Panel (Electro-Optical Device) 51 Screen Main Body (Screen) ) 52A1 receiving surface 52A2 supporting surface 52B screen holding portion (pressing member) 52D elastic member O1 center of gravity position O2 projection point

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G02F 1/1333 G02F 1/1333 5C058 G03B 21/10 G03B 21/10 Z 21/62 21/62 H04N 5 / 74 H04N 5/74 FF term (reference) 2H021 AA05 BA24 2H042 BA04 BA12 BA19 2H088 EA14 EA15 HA13 HA21 HA24 MA01 2H089 HA40 KA15 QA06 QA08 2K103 AA01 AA05 AA11 AA17 AA25 AB08 CA01 CA06 CA23 5C0 CA23 CA23 5A0

Claims (3)

[Claims] 1. An electro-optical device that modulates a light beam emitted from a light source to form an optical image according to image information, and an image forming unit including a projection optical system that magnifies and projects the optical image, and an image forming unit. A rear projector including a box-shaped housing for housing a unit, and a screen that is provided to be exposed on any side surface of the box-shaped housing and projects the optical image formed by the image forming unit. And the housing includes a receiving surface that is formed along an outer peripheral edge of the screen and receives the screen in an out-of-plane direction, and the receiving surface is formed to be inclined with respect to a vertical direction. Is attached, a projection point obtained by vertically projecting the center of gravity of the screen onto a support surface is included in the receiving surface. 2. The rear projector according to claim 1, wherein the receiving surface is provided on a front surface side of the screen, and the rear surface side of the screen presses the screen from the rear surface side to the receiving surface side. A rear projector comprising a pressing member. 3. The rear projector according to claim 2, wherein an elastic member is interposed between the pressing member and the back surface of the screen.