JP2002107820A - Projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To project and display a normal picture long sideways, while arranging an electric-optical device and a color light combining means along a surface nearly perpendicular in the short-length direction of a projected image. SOLUTION: The color synthesizing means of a projector to project a nearly rectangular image is arranged, so that the directions of two kinds of crossed lines by a dichroic surface are made nearly in parallel with the short-length direction of the projected image. The electric optical device respectively possesses a nearly rectangular image forming area, and is arranged so as to be counterposed to an incident plane respectively, corresponding among three incident planes in parallel with the crossed line, so that the long side direction of an image forming area is aligned with the direction of the crossed lines. Three electric optical devices and color combining means are arranged along the surface nearly perpendicular in the short side direction of the projected image, and three electric-optical devices and cross-dichroic prisms are arranged along a nearly horizontal surface. A color image formed by the cross-dichroic prism is rotated by a prescribed angle by centering a shaft perpendicular to the screen of the color image by plural mirrors.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a projector (projection display device) for projecting a color image.

[0002]

2. Description of the Related Art As a display device having a large screen, a projector for enlarging and projecting an image on a screen for display is often used. As a projector for projecting a color image, three electro-optical devices such as a liquid crystal panel are used as light valves to form three color component images constituting a color image, and a cross dichroic prism is used as a color synthesizing means. A projector of a type that forms a color image by combining three color component images with each other is known. Such a projector may be referred to as a “three-panel projector”.

In such a three-plate type projector, three electro-optical devices are connected to each other in a substantially rectangular shape for the purpose of downsizing the device by reducing the size of the cross dichroic prism, reducing the cost, suppressing color unevenness, and the like. In some cases, the configuration is such that the direction of the long side of the image forming region of the shape is aligned with the direction of the line of intersection of the two types of dichroic surfaces of the cross dichroic prism. For example, JP-A-11-249070 and JP-A-2000-122
An example described in Japanese Patent No. 174 is cited.

[0004]

However, in a projector in which the three electro-optical devices are arranged as described above, the short side of the image forming area is used in order to make the projected and displayed image a general horizontally long image. It is necessary to three-dimensionally dispose three electro-optical devices, a cross dichroic prism, and other optical elements in a plane including the direction. For this reason, the overall projector becomes tall and has a vertically long appearance. In addition, there is a disadvantage that it is difficult to manufacture an optical system. Another disadvantage is that it is difficult to efficiently cool the electro-optical device.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the prior art, and comprises an electro-optical device and a color light synthesizing means which are substantially perpendicular to the direction of the short side of the projected image displayed on the projection surface. It is an object of the present invention to provide a technique capable of projecting and displaying a general horizontally long image while arranging it along a plane.

[0006]

In order to solve at least a part of the problems described above, an apparatus of the present invention provides a projector for displaying a substantially rectangular image on a projection surface as a projection image. And has three electro-optical devices for forming three color component images, and two types of dichroic surfaces arranged in a substantially X-shape, and synthesizes the three color component images to form a color image. And a projection lens for projecting a color image formed by the color synthesizing means, wherein the direction of the line of intersection of the two types of dichroic surfaces is Each of the electro-optical devices has a substantially rectangular image forming area, and the direction of the long side of the image forming area is the same as the direction of the short side of the projected image. Matches the direction of the line As such, among the three incident surfaces of the color synthesizing means parallel to the line of intersection of the color synthesizing means, it is arranged opposite to the incident surface corresponding to each of the three
The two electro-optical devices and the color synthesizing unit are arranged along a plane substantially perpendicular to the direction of the short side of the projected image,
The projector further reflects the color image formed by the color synthesizing unit so that the direction of the long side of the color image formed by the color synthesizing unit is oriented in the direction of the long side of the projected image. A plurality of mirrors.

The plurality of mirrors reflect the color image formed by the color synthesizing unit such that the direction of the long side of the color image formed by the color synthesizing unit is oriented toward the long side of the projected image. Therefore, a vertically long image (horizontally oriented image) synthesized by the color synthesizing unit can be used as a general horizontally long image. Therefore, the color synthesizing means can be arranged such that the direction of the line of intersection is substantially parallel to the direction of the short side of the projected image. In addition, the three electro-optical devices may be configured so that the direction of the long side of each of the image forming regions coincides with the direction of the line of intersection of the color synthesizing unit. , Can be arranged to face the corresponding incident side surfaces. This makes it possible to project and display a general horizontally long image while arranging the electro-optical device and the color light synthesizing means in a substantially direction substantially perpendicular to the direction of the short side of the projected image.

Further, since the color image formed by the color synthesizing means is reflected by a plurality of mirrors, the same optical path length can be secured in a small space as compared with the case of reflecting by a single mirror. Thereby, the size of the device can be reduced.

The plurality of mirrors have a predetermined angle such that the direction of the long side of the color image formed by the color synthesizing means in the screen is the same as the direction of the long side of the projected image in the screen. And at least two mirrors can be configured by arranging the at least two mirrors such that normals passing through the centers of the respective reflecting surfaces do not cross each other.

In the above projector, it is preferable that the predetermined angle is 90 degrees.

With this arrangement, the projection section and the plurality of mirrors can be easily arranged.

In the above projector, it is preferable that at least one of the plurality of mirrors is disposed integrally with the projection lens.

In this case, since the space for disposing at least one mirror can be reduced, the size of the apparatus can be reduced. Note that the phrase “disposed integrally” includes not only a case where the projection lens is disposed integrally with the vicinity of the entrance surface or the exit surface of the projection lens but also a case where the projection lens is disposed inside the projection lens.

Here, it is preferable that at least one mirror arranged integrally with the projection lens is constituted by a total reflection prism.

With this configuration, it is possible to easily realize a reflection surface having a high reflectance, and to realize a high alignment accuracy with an adjacent lens body.

In the above projector, it is preferable that each of the three electro-optical devices has a signal input terminal on a side having a long side of the image forming area.

A signal input terminal of an electro-optical device conventionally used in a projector is provided on a side having a long side of an image forming area. Therefore, according to the projector, a conventional electro-optical device can be used.

Here, the signal input terminal has a signal line formed so as to extend from the side having the long side of the image forming area to the side having the short side, and extends along the long side direction. Preferably, the signal line has a three-dimensionally bent shape such that the width of the signal line is reduced.

With this arrangement, the space required for the signal input terminal can be reduced.

The electro-optical device disposed on the first incident surface side parallel to the exit surface of the color synthesizing means is referred to as a first electro-optical device, and a second incident light perpendicular to the first incident surface is provided. The electro-optical device arranged on the surface side is a second electro-optical device,
If the electro-optical device disposed on the third incident surface side parallel to the second incident surface is a third electro-optical device, the first
One of the signal input terminals of the first and second electro-optical devices is surrounded by a component of a relay optical system disposed in an optical path of light illuminating the second electro-optical device and the color combining unit. Preferably, it is arranged in a spatial region.

With this arrangement, the spatial area surrounded by the components of the relay optical system and the color synthesizing means is used to make the
The signal input terminals of the first and second electro-optical devices can be arranged.

Further, the three electro-optical devices include an electro-optical device disposed on a first incident surface side parallel to an emission surface of the color synthesizing unit, and second and second electro-optical devices perpendicular to the first incident surface. It is preferable that the electro-optical device disposed on the third incident surface side be composed of two types of electro-optical devices whose driving directions in the long side direction of each image forming area are opposite to each other.

In this case, since the three electro-optical devices can be constituted by two types of electro-optical devices, it is easy to optimize the electro-optical devices.

Further, in the three electro-optical devices, an electro-optical device disposed on a first incident surface side parallel to an emission surface of the color synthesizing means is a first electro-optical device, and The electro-optical device disposed on the second incident surface side perpendicular to the plane is referred to as a second electro-optical device, and the electro-optical device disposed on the third incident surface side parallel to the second incident surface is referred to as a second electro-optical device. According to the third electro-optical device, the driving direction of the second electro-optical device in the long side direction of the image forming area is opposite to the first electro-optical device, and the driving direction of the third electro-optical device is The driving direction in the short side direction of the image forming area is the first
It is preferable that three types of electro-optical devices that are opposite to each other are used.

In this case, the signal input terminals of the three electro-optical devices can be arranged in different spatial regions, respectively, so that the configuration of the devices is easy.

[0026]

DETAILED DESCRIPTION OF THE INVENTION First Embodiment: Next, an embodiment of the present invention will be described based on an embodiment. FIG. 1 is an explanatory diagram showing a schematic configuration of a rear projector (rear projection display device) as a first embodiment of the present invention. As shown in the perspective view of FIG.
Projection unit PJ and two projection light reflecting mirrors M
R1 and MR2 and a rear screen SCR are provided.

In the following, the direction of the optical axis of the projection light from the projection unit PJ is defined as the y direction, the 3 o'clock direction as the + y direction, and the 12:00 o'clock direction as the z direction. Let the xy plane be the horizontal plane. Further, in order to facilitate the description of the direction of light, the direction of the central axis of light will be described as the direction of light.

A1. Projection part PJ: FIG.
FIG. 3 is a schematic plan view illustrating a main part of an optical system of a projection unit PJ. The projection unit PJ includes the illumination optical system 10.
0, color light separation optical system 200, and relay optical system 300
And three light valves 400R, 400G, 400B
, A cross dichroic prism 500, and a projection lens 600. Each component is arranged along a substantially horizontal surface (that is, an xy plane) around the cross dichroic prism 500. For this reason, as shown in FIG. 1A, the projection part PJ has a short, horizontally long shape as a whole.

The illumination optical system 100 includes a light source 110, an integrator optical system 120, and an illumination light reflecting mirror 130. The light emitted from the light source 110 uniformly illuminates the light valves 400R, 400G, and 400B to be illuminated via the integrator optical system 120. The illumination light reflecting mirror 130 has a function of reflecting the illumination light emitted from the integrator optical system 120 in the direction of the color light separation optical system 200. The illumination light reflecting mirror 130 may be arranged in the optical path in the integrator optical system 120 in some cases. The illumination light reflecting mirror 130
May be omitted depending on the arrangement of the light source 110 and the integrator optical system 120. The polarization conversion optical system 140 converts the non-polarized light into light valves 400R,
It has a function of aligning with polarized light having a polarization direction usable in 400G and 400B.

The color light separation optical system 200 includes two dichroic mirrors 210 and 220 and a reflection mirror 230, and functions to separate the illumination light emitted from the illumination optical system 100 into three color lights of different wavelength ranges. have.

The first dichroic mirror 210 allows red (R) light to pass therethrough and emits color light (substantially green (G) light and blue (B) light) on a shorter wavelength side than the transmitted color light. reflect. The R light transmitted through the first dichroic mirror 210 is reflected by the reflection mirror 230, passes through the field lens 240, and enters the R light valve 400R.

Of the G light and the B light reflected by the first dichroic mirror 210, the G light is reflected by the second dichroic mirror 220 and
The light passes through 50 and enters the G light valve 400G. On the other hand, the B light is transmitted through the second dichroic mirror 220 and relay optical system 300, that is, the incident side lens 31
0, first relay reflection mirror 320, relay lens 33
0, the light enters the light valve 400B for B via the second relay reflection mirror 340 and the emission side lens 350. Here, the reason that the relay optical system 300 is used for the B light is that the length of the optical path of the B light is longer than the length of the optical paths of the other color lights, so that the reduction of the light use efficiency due to light diffusion or the like occurs. This is to prevent it.

Light valves 400R, 400 for each color
G and 400B modulate the color lights incident on them in accordance with the corresponding color signals (image information), and emit the modulated light as transmitted light. A transmissive liquid crystal panel is used as such a transmissive light valve. The light valves 400R, 400G, and 400B correspond to the electro-optical device of the present invention, and the image represented by the modulated light of each color corresponds to the color component image of each color forming the color image.

FIG. 3 shows a cross dichroic prism 5.
00 and light valves 400R, 400G, 40 for each color
It is a schematic perspective view which shows OB. The cross dichroic prism 500 is disposed such that an intersection line 530 at which the first dichroic surface 510 and the second dichroic surface 520 intersect is perpendicular to the xy plane, that is, the horizontal plane. Also, the four side surfaces 550, 560, 5
70, 580, the first side surface, that is, the exit surface 5
50 and the second side surface 560 are parallel to the xz plane,
And the fourth side surfaces 570 and 580 are arranged to be parallel to the yz plane. Second to fourth side surfaces 56
At 0, 570, and 580, light valves 400G, 400B, and 400R for the corresponding colors are arranged. These light valves 400R, 400G, 400
B is the direction of the long side (long side direction) ls of the substantially rectangular image forming area (light irradiation surface) in the direction of the intersection line 530 (intersection direction);
That is, they are arranged vertically long so as to coincide with the z direction. Hereinafter, such an arrangement may be referred to as a “vertical arrangement”.

Incidentally, the second side surface 560 corresponds to the first incident surface of the present invention. Further, the third side surface 570 corresponds to the second incident surface of the present invention, and the fourth side surface 580 corresponds to the third side surface.

The R light emitted from the R light valve 400R is reflected by the first dichroic surface and emitted from the emission surface 550. Also, the light valve 40 for B
The B light emitted from OB is reflected by the second dichroic surface and emitted from the emission surface 550. Further, the G light emitted from the G light valve 400G passes through the first dichroic surface 510 and the second dichroic surface 520 and is emitted from the emission surface 550. Thereby, the light valves 400R, 400G, 40 for each color are provided.
The modulated lights of three colors modulated at 0B are combined by the cross dichroic prism 500. The color image represented by the combined modulated light is projected by the projection lens 600. However, the cross dichroic prism 500
The color image synthesized by the light valve 400R, 4
00G, 400B, the long side becomes a vertically long image in the z direction corresponding to the vertically long arrangement. On the other hand, the image displayed on the screen SCR after being projected by the projection lens 600 is horizontally long in which the long side is in the y direction. Image. Note that light representing a color image is emitted in the + y direction.

The configuration and function of each part of the projector as shown in FIG. 2 are described in, for example, JP-A-10-177151 and JP-A-1
Since it is described in detail in Japanese Patent Application Laid-Open No. 0-186548, detailed description is omitted in this specification.

A2. Arrangement of projection light reflection mirrors MR1 and MR2: The second projection light reflection mirror MR2 is arranged to reflect the projection light from the projection unit PJ traveling in the + y direction in the + z direction, as shown in FIG. Have been. Specifically, the normal line n2 on the reflection surface of the second projection light reflection mirror MR2 is arranged so as to be parallel to the yz plane and have a 45-degree inclination clockwise with respect to the y-axis. ing. Also, the first projection light reflection mirror MR1
Are arranged so as to reflect the projection light from the second projection light reflection mirror MR2 traveling in the + z direction in the + x direction, as shown in FIG. Specifically, the normal n1 on the reflection surface of the first projection light reflection mirror MR1 is 45 parallel to the xz plane and counterclockwise with respect to the z axis.
It is arranged to have a degree inclination. That is, the first and second projection light reflection mirrors MR1 and MR2 are arranged at twisted positions where the normals n1 and n2 on the respective reflection surfaces do not cross each other. Rear screen SCR
Are arranged parallel to the yz plane.

With the projection unit PJ and the two projection light reflection mirrors MR1 and MR2 arranged as described above, the projection light from the projection unit PJ is reflected by the second projection light reflection mirror MR2 and the first projection light reflection. The light is reflected by the mirror MR1 and enters the rear screen SCR.

Here, the two projection light reflecting mirrors MR1, MR1,
MR2 determines the direction of the long side of the image projected from the projection unit PJ in the screen by using the rear screen SCR.
Is rotated by 90 degrees so that the direction of the long side of the image projected on the screen is oriented. As a result, as shown in FIG. 1A, the horizontal arrow image projected from the projection unit PJ becomes an upward arrow graphic by the two projection light reflecting mirrors MR1 and MR2 arranged at the twist positions. And projected on the rear screen SCR.

As described above, in the rear projector 10 of the present embodiment, the three light valves 400R, 400G, 400B in the projection section PJ are used.
With the configuration in which the long side direction of the image forming area of FIG. 1 is made to coincide with the direction of the intersection line 530 of the cross dichroic prism 500, each component of the optical system that constitutes the projection unit PJ is used for the image projected on the screen SCR. A plane perpendicular to the direction of the short side (z direction in FIG. 1A) (FIG. 1A)
(Xy plane), a general horizontally long image can be projected and displayed.

In the rear projector 10 of this embodiment, since the two projection light reflecting mirrors MR1 and MR2 are arranged at the twisted positions, the projection unit PJ is arranged in a state substantially parallel to the screen SCR. Therefore, the depth and height of the rear projector 10 (FIG. 1A)
X and z directions) can be shortened, and the size of the entire apparatus can be reduced.

By the way, the second projection light reflecting mirror can be arranged as follows. FIG. 4 is an explanatory diagram showing an example in which the second projection light reflection mirror MR2 is arranged in the projection lens of the projection unit PJ. Projection lens 6
00 is a compound lens composed of a plurality of lenses as shown in FIG. 4A (FIG.
An example in which one lens is used is shown). Therefore, FIG.
As shown in (B), as the projection lens of the projection unit PJ, a projection lens 600 ′ in which a second projection light reflection mirror MR2 is arranged in the optical path of the compound lens may be used. By using such a projection lens 600 ′, the arrangement space of the second projection light reflection mirror MR2 in FIG. 1 can be reduced, so that the size of the rear projector can be further reduced. When the second projection light reflection mirror MR2 is arranged in the projection lens, it is preferable that the projection light reflection mirror be constituted by a total reflection prism. According to the total reflection prism, a mirror having a high reflectance can be easily formed in the projection lens.

Further, the projection light reflecting mirror MR2 is shown in FIG.
As shown in (B), not only a configuration arranged in the middle of a plurality of lenses but also a configuration integrally arranged on the incident surface or the exit surface side of the projection lens may be adopted.

A3. Light valves 400R, 400G,
Arrangement of 400B: FIG. 5 is an enlarged schematic plan view showing the periphery of the cross dichroic prism 500. In general, the signal input terminal of the light valve is provided on the side having the long side of the image forming area (hereinafter sometimes simply referred to as “long side”). Therefore, in the projection part PJ, the light valves 400R, 400
When arranging G and 400B, it is necessary to consider an arrangement space for each signal input terminal provided on the long side. Specifically, the light valve 4 for G
The signal input terminals 410G and 410B of the light valve 400B for 00G and B are connected to the relay optical system 300.
Are arranged in a space area SP1 (area indicated by a broken-line circle in the figure) surrounded by the entrance-side lens 310, the relay lens 330, the exit-side lens 350, the field lens 250, and the cross dichroic prism 500. .
Further, the signal input terminal 41 of the light valve 400R for R is used.
OR is arranged so as to be in the space area SP3 on the projection lens 600 side.

FIG. 6 is a schematic front view of the light valves 400R, 400G, and 400B for the respective colors in the arrangement shown in FIG. 5 as viewed from the light incident surface side (light irradiation surface side). The solid arrow in the figure indicates the driving direction related to the long side direction of the image forming area,
It shows the driving direction with respect to the short side direction. In addition, the broken arrow indicates the clear viewing direction. In the arrangement shown in FIG. 5, with reference to the light valve for G shown in FIG. 6B, as shown in FIGS. 6A and 6C, the light valve 400R for R and the light for B are shown. As the bulb 400B, a type of light valve whose driving direction in the long side direction is opposite and whose clear viewing direction is symmetric with respect to the short side direction is used.
That is, three light valves can be constituted by two types of light valves.

As shown in FIG. 5, an arrangement for a signal input terminal is provided in a space area SP2 surrounded by two field lenses 240 and 250, a cross dichroic prism 500, and a first dichroic mirror 210. If there is a space, the signal input terminal 410R of the light valve 400R for R and the signal input terminal 410G of the light valve 400B for G may be arranged in this space area SP2. However, the size of the light beam incident on the first dichroic mirror 210 from the illumination optical system 100 depends on the light valves 400R, 400G, and 4 for the respective colors.
00B, which is larger than the size of the light beam
The dichroic mirror 210 needs to have a considerably large color light separation surface (dichroic surface). For this reason,
In most cases, the space area SP2 has almost no space for arranging signal input terminals. On the other hand, the light beam passing through the relay optical system 300 is considerably condensed, and the size thereof is considerably smaller than the size of the light beam incident on the first dichroic mirror 210. Therefore, in the space area SP1, a space for arranging the signal input terminal 410G of the light valve 400G for G and the signal input terminal 410B of the light valve 400B for B can be secured.

FIG. 7 is an explanatory diagram showing the signal input terminal 410G of the G light valve 400G. The signal input terminal 410G of the light valve 400G is shown in FIG.
As shown in FIG. 2, the upper surface is formed so as to extend from the long side to the short side. This signal input terminal 41
In 0G, a plurality of signal lines are formed in a plane using an FPC (flexible printed circuit), and the cross-sectional shape along the line AB is planar as shown in FIG. 7B. However, the cross-sectional shape in the middle part of the FPC is not planar, and for example, the cross-sectional shape along the line CD is shown in FIG.
(C) three-fold shape, or
As shown in FIG. 7 (D), it has a three-dimensional shape such as a shape bent in a U-shape. As described above, if the signal input terminal 410G has a structure in which a plurality of signal lines are three-dimensionally assembled in the middle part, the space required in one direction (the x direction in FIG. 5) of the signal input terminal 410G is reduced. be able to. Further, by extending the signal input terminal 410G from the long side to the short side, it is possible to secure a flow path in the vertical direction (z direction in FIG. 5) of the cooling air, so that the cooling efficiency can be improved.

It should be noted that the light valves 400R for other colors,
Since 400B is the same, the description is omitted.

FIG. 8 shows a cross dichroic prism 5.
It is another schematic plan view which expands and shows the periphery of 00. In this example, the signal input terminal 4 of the light valve 400G for G is used.
Only 10G is arranged in the space area SP1. The signal input terminal 410 of the light valve 400R for R
R is arranged so as to be in the space area SP3 on the projection lens 600 side, and the signal input terminal 410B of the light valve 400B for B is arranged so as to be in the space area SP4 on the projection lens 600 side.

FIG. 9 is a schematic front view of the light valves 400R, 400G, 400B in the arrangement shown in FIG. 8, as viewed from the light incident surface side. The solid arrows in the drawing indicate the driving direction in the long side direction and the driving direction in the short side direction of the image forming area. In addition, the broken arrow indicates the clear viewing direction. In the case of the arrangement shown in FIG. 8, FIG. 9 (A), (B),
As shown in (C), three light valves 400R, 4
Different types of light valves are used for 00G and 400B. Specifically, with reference to the light valve 400B for G in FIG. 9B, the light valve 400R for R has the long side direction opposite to the driving direction as shown in FIG. 9A. A light valve whose clear viewing direction is opposite is used. As the light valve 400B for B, as shown in FIG. 9C, a light valve whose driving direction in the short side direction is opposite and whose clear viewing direction is symmetric with respect to the long side direction is used.

In the case of the arrangement shown in FIG. 8, the input terminals 410 of the light valves 400R, 400G, 400B for each color.
Since R, 410G, and 410B may be arranged in different spatial regions SP1, SP3, and SP4, the arrangement is easy. However, it is necessary to use three types of light valves as shown in FIG. In this regard, the arrangement shown in FIG. 5 is more advantageous since two types of light valves may be used.

B. Second Embodiment FIG. 10 is an explanatory diagram showing the rear projector 20 of the second embodiment in comparison with the rear projector 10 of the first embodiment. In the rear projector 20 of the second embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted below. In the rear projector 10 of the first embodiment, the projection light from the projection unit PJ that travels in the + y direction is reflected by the second projection light reflection mirror MR2 and travels in the + z direction, as shown in FIG. First projection light reflection mirror MR1
, And travels in the + x direction to enter the rear screen SCR. For this reason, the second projection light reflection mirror MR2
The normal n2 on the reflection surface is arranged so as to be parallel to the yz plane and to have a 45-degree inclination clockwise with respect to the y-axis (FIG. 1C). The first projection light reflecting mirror MR1 has a normal line n on its reflection surface.
1 are arranged so as to be parallel to the xz plane and have a tilt of θ1 (= 45 degrees) in a counterclockwise direction with respect to the z axis.

On the other hand, as shown in FIG. 10B, in the rear projector 20 of the second embodiment, the projection light from the projection unit PJ traveling in the + y direction is reflected by the second projection light reflection mirror MR2, The light advances in a direction inclined by α degrees counterclockwise with respect to the + z direction, further reflects on the first projection light reflecting mirror MR1, advances in the + x direction, and enters the rear screen SCR. Therefore, the second embodiment of the second embodiment
Is arranged by rotating the second projection light reflection mirror MR2 of the first embodiment counterclockwise by an angle α around a central axis parallel to the y-axis. In the first projection light reflection mirror MR1, the normal n1 on the reflection surface is θ2 (= (45 + α / 2)) degrees parallel to the xz plane and counterclockwise with respect to the z axis. Are arranged so as to have the inclination of. That is, similarly to the first embodiment, the first and second projection light reflecting mirrors MR1 and MR2
Are arranged at twisted positions where the normals n1 and n2 on the respective reflecting surfaces do not intersect each other.

However, θ2> θ1 (0 <α <90). Therefore, the inclination of the first projection light reflection mirror MR1 in the second embodiment with respect to the yz plane can be made smaller than the inclination of the first projection light reflection mirror MR1 in the first embodiment. Thereby, the rear projector 20 of the second embodiment is
Can be configured to be thinner than the rear projector 10 of the first embodiment.

Note that the rear projector 10 of the first embodiment
Is α = α in the rear projector 20 of the second embodiment.
Equivalent to 0.

However, in the rear projector 20,
It is preferable that the projection unit PJ be disposed so as to be rotated by α degrees counterclockwise around a central axis parallel to the y-axis with respect to a horizontal plane (xy plane).

Therefore, "the three electro-optical devices and the color synthesizing means are arranged along a plane substantially perpendicular to the direction of the short side of the projected image" of the present invention is as described in the first embodiment. ,
Not only when an optical system including a light valve (electro-optical device) and a color combining unit (cross dichroic prism) is arranged along a plane (that is, an xy plane) perpendicular to the direction of the short side of the projection image, As described above, the case where the optical system is inclined and disposed by inclining the projection unit PJ by α degrees is also included.

C. Third Embodiment FIG. 11 is an explanatory diagram showing a schematic configuration of a rear projector as a third embodiment. This rear projector 30 is different from the rear projector 10 (FIG. 1A) of the first embodiment in that the projection light from the projection unit PJ is reflected by two projection light reflecting mirrors MR1 and MR2, while FIG. As shown in the perspective view of A), two projection light reflecting mirrors MR1 and MR2
In addition, another projection light reflecting mirror MR3 is added, and the projection light from the projection unit PJ is reflected by the three projection light reflecting mirrors. In the rear projector 30 according to the third embodiment, the same components as those of the rear projector 10 according to the first embodiment are denoted by the same reference numerals, and description thereof will be omitted below.

The third projection light reflecting mirror MR3 is arranged as shown in FIG.
As shown in (C), it is arranged so that the projection light from the projection unit PJ traveling in the + y direction is reflected in the -z direction. Specifically, the third projection light reflection mirror MR3
Are arranged in such a manner that the normal line n3 on the reflection surface is parallel to the yz plane and has an inclination of 45 degrees counterclockwise with respect to the y-axis. Second projection light reflecting mirror M
As shown in FIG. 11B, R2 reflects the projection light from the third projection light reflection mirror MR3 traveling in the −z direction in a direction inclined α degrees counterclockwise with respect to the + z direction. Are arranged as follows. Specifically, the normal line n2 on the reflection surface of the second projection light reflection mirror MR2 is parallel to the xz plane and α / 2 degrees counterclockwise with respect to the z axis (0 <α < 90). Further, the first projection light reflecting mirror MR1 is configured as shown in FIG.
As shown in (B), the projection light from the second projection light reflection mirror MR2 that advances at an inclination of α degrees with respect to the + z direction is arranged to be reflected in the + x direction. Specifically, the first
Normal n1 on the reflection surface of the projection light reflection mirror MR1
Are arranged so as to be parallel to the xz plane and have an inclination of (45 + α / 2) degrees clockwise with respect to the z axis. That is, the second projection light reflection mirror MR2 and the third projection light reflection mirror MR3 are arranged at twisted positions where the normals n2 and n3 on the respective reflection surfaces do not cross each other. The rear screen SCR is arranged parallel to the yz plane.

By arranging the projection unit PJ and the three projection light reflection mirrors MR1 to MR3 as described above, the projection light from the projection unit PJ is reflected from the third projection light reflection mirror MR3 to the first projection light reflection. The light is reflected by the mirror MR1 and enters the rear screen SCR.

Here, the two projection light reflecting mirrors MR3 and MR3
The MR2 sets the direction of the long side of the image projected from the projection unit PJ in the screen to the direction of the long side in the screen of the image after reflection, that is, the image projected on the rear screen SCR. Rotate 90 degrees clockwise about a central axis perpendicular to. The first projection light reflection mirror MR1 reflects the image reflected by the second projection light reflection mirror MR2 in the direction of the rear screen SCR without causing rotation of the image. As a result, FIG.
As shown in the figure, the horizontal arrow image projected from the projection unit PJ is rotated by the two projection light reflection mirrors MR3 and MR2 arranged at the twisted positions so as to form an upward arrow graphic, and the rear screen is rotated. SCR
Projected above. Thus, also in the present embodiment, the three light valves 400R,
The respective components of the optical system constituting the projection unit PJ are projected onto the screen SCR while keeping the configuration in which the long side directions of the image forming areas of 400G and 400B coincide with the direction of the intersection line 530 of the cross dichroic prism 500. It is possible to project and display a general horizontally long image while arranging it along a plane (xy plane in FIG. 11A) perpendicular to the short side direction (z direction in FIG. 11A) of the image. it can.

The rear projector 30 according to the present embodiment
Has a configuration in which the projection light from the projection unit is reflected by the three projection light reflection mirrors MR1 to MR3. Therefore, even when a projection lens having a long projection distance is used, the projection light from the projection unit is The size of the entire apparatus can be reduced as compared with a rear projector configured to reflect light by the projection light reflecting mirror.

Note that the first projection light reflecting mirror MR1 is
The normal line n1 on the reflection surface is parallel to the xz plane and (45 + α / 2) in a counterclockwise direction with respect to the z axis.
It is arranged so as to have a degree inclination, and depends on the inclination α of the projection light from the second projection light reflection mirror MR2. Accordingly, similarly to the second embodiment, the inclination of the first projection light reflection mirror MR1 with respect to the yz plane can be changed according to the inclination of the projection light from the second projection light reflection mirror MR2. The configuration can be thinner than the rear projector 10 of the embodiment.

D. Fourth Embodiment In the first to third embodiments, the case where the projection unit PJ in which the transmission type liquid crystal panel is used as the light valve is used as an example, but the reflection type liquid crystal panel is applied. A projection unit can also be used.

FIG. 12 is a schematic plan view showing a main part of an optical system of a projection unit PJ 'using a reflection type liquid crystal panel as a light valve. Projection part PJ '
Is an illumination optical system 100, a color light separation optical system 200 ′,
Relay optical system 300 'and polarizing beam splitter 700
R, 700G, 700B and light valve 400R ',
400 G ′, 400 B ′, a cross dichroic prism 500, and a projection lens 600. Each component is arranged substantially horizontally around the cross dichroic prism 500.

The light emitted from the bright optical system 100 enters the color light separation optical system 200 'and is separated into three color lights.
The first dichroic mirror 210 'reflects the B light and reflects the color light (G light and R light) on the longer wavelength side than the B light.

Of the G light and R light transmitted through the first dichroic mirror 210 ′, the R light also transmits through the second dichroic mirror 220 ′, and
0, and enters the R polarization beam splitter 700R. The G light is reflected by the second dichroic mirror 220 ′, and enters the G polarizing beam splitter 700G through the field lens 250.

The B light reflected by the first dichroic mirror 210 'passes through the relay optical system 300', that is, the incident side lens 310, the relay reflecting mirror 320, the relay lens 330, and further passes through the exit side lens 350. Incident on the polarization beam splitter 700B for B.

The polarization beam splitter 700R for each color,
Each color light incident on 700G and 700B is separated into two types of polarized light (s-polarized light and p-polarized light) by the polarization splitting surfaces 710R, 710G and 710B of the corresponding polarizing beam splitters 700R, 700G and 700B. The light valves 400R ', 400G', 400B 'for each color are provided with the corresponding polarizing beam splitters 700R, 700G, 700B.
Are arranged on the optical axis of one of the polarized lights emitted from the light source. In the example of the figure, each polarization beam splitter 700
R, 700G, 700B polarization separation surfaces 710R, 710
G and 710B reflect s-polarized light and transmit p-polarized light, and the light valves 400R 'and 400
G ′ and 400B ′ are arranged on the optical axis of the s-polarized light. Therefore, each color light of the s-polarized light enters the corresponding light valve 400R ', 400G', 400B 'as illumination light.

Light valves 400R ', 400 for each color
G ′ and 400B ′ modulate the respective color lights incident as illumination light according to the corresponding color signals (image information), and emit the reflected light. As such reflective light valves 400R ', 400G', and 400B ', reflective liquid crystal panels are used.

The light valves 400R ', 4 for each color
00G 'and 400B' are light valves 400R, 400G and 400B of each color in the projection part PJ.
It is arranged vertically long like.

Light valves 400R ', 400 for each color
The light emitted from G ′ and 400B ′ re-enters the corresponding color beam splitters 700R, 700G and 700B. The re-entered color lights are mixed lights containing modulated light (p-polarized light) and unmodulated light (s-polarized light). Therefore, of the emission lights of each color, only the modulated light corresponds to the polarization beam splitters 700R and 700R.
G, 700B polarization separation surfaces 710R, 710G, 710
B passes through and enters the cross dichroic prism 500.

Each color light incident on the cross dichroic prism 500 is synthesized and emitted toward the projection lens 600. Thus, the color image represented by the light synthesized by the cross dichroic prism 500 is projected by the projection lens 600. However, the directions of the color images synthesized by the cross dichroic prism 500 are the light valves 400R ', 400G', 4
The image becomes a horizontal image in the x or z direction corresponding to the portrait arrangement of 00B '.

In the projection section PJ 'of this embodiment, the signal input terminal of the light valve 400G' may be arranged in a space surrounded by the relay lens 330, the entrance lens 310 and the polarizing beam splitter 700G. It is possible to use a light valve having a signal input terminal arranged on the long side.

E. Modifications: The present invention is not limited to the above-described examples and embodiments, and can be carried out in various modes without departing from the gist thereof. For example, the following modifications are also possible. is there.

(1) In the above embodiment, a rear projector using two or three projection light reflecting mirrors has been described as an example. However, the present invention is not limited to this, and four or more projection light reflecting mirrors may be used. The used rear projector may be used. That is, the present invention can be applied to a rear projector including a plurality of projection light reflecting mirrors. Then, between a plurality of projection light reflecting mirrors that cause rotation of an image, it is only necessary that the projection light reflecting mirrors be arranged at twisted positions where their normals do not cross each other.

(2) In the above embodiment, the rear projector is described as an example. However, the present invention can be applied to a front projection type projector (front projector). In the case of a rear projector, an image is displayed by light transmitted through the rear screen SCR, while in the case of a front projector, an image is displayed by light reflected from the screen. In the front projector, since the projection unit and the screen cannot be integrated, it is necessary to arrange all of the projection light reflecting mirrors before, after, or inside the projection lens.

FIG. 13 shows two projection light reflecting mirrors MR.
FIG. 1 is an explanatory diagram showing an example in which MR2 is arranged in a projection lens. The projection lens 600 ″ is a second partial lens 61 of the three partial lenses 611, 612, and 613.
2 and the third partial lens 613, two projection light reflecting mirrors MR1 and MR2 are arranged. The two reflecting mirrors MR1 and MR2 may be arranged between the first partial lens 611 and the second partial lens 612. The second projection light reflection mirror MR2 is located between the first partial lens 611 and the second partial lens 612, and the first projection light reflection mirror MR1 is located between the second partial lens 612 and the third partial lens. 613. That is, the plurality of projection light reflecting mirrors may be arranged at any position in the projection lens. Further, the two projection light reflecting mirrors MR1 and MR2 do not necessarily need to be arranged in the projection lens, and project on the incident surface side of the first partial lens 611 or the emission surface side of the third partial lens 613. You may make it arrange | position with a lens integrally. Further, one of the two projection light reflecting mirrors MR1 and MR2 is arranged in the projection lens, and the other is the first partial lens 61.
It may be arranged integrally with the projection lens on the first incident surface side or on the exit surface side of the third partial lens 613.

The two projection light reflection mirrors MR1 and MR2 arranged in the projection lens 600 ″ are the same as the second projection light reflection mirror MR in the projection lens 600 ′ of FIG.
As in the case of 2, it is preferable to configure the device with a total reflection prism.

(3) In the above embodiment, the cross dichroic prism is used as the color synthesizing means. However, a cross dichroic mirror can be used instead.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a rear projector as a first embodiment of the present invention.

FIG. 2 is a schematic plan view illustrating a main part of an optical system of a projection unit PJ.

FIG. 3 is a schematic perspective view showing a cross dichroic prism 500 and light valves 400R, 400G, and 400B for each color.

FIG. 4 is an explanatory diagram showing an example in which a second projection light reflection mirror MR2 is arranged in a projection lens of a projection unit PJ.

FIG. 5 is a schematic plan view showing the periphery of a cross dichroic prism 500 in an enlarged manner.

6 is a schematic front view of the light valves 400R, 400G, and 400B for each color in the arrangement shown in FIG. 5 as viewed from the light incident surface side.

FIG. 7 is a signal input terminal 4 of a light valve 400G for G.
It is explanatory drawing shown about 10G.

FIG. 8 is another schematic plan view showing the periphery of the cross dichroic prism 500 in an enlarged manner.

FIG. 9 shows a light valve 400 in the arrangement shown in FIG.
It is the schematic front view which looked at R, 400G, and 400B from the light-incidence surface side.

FIG. 10 is an explanatory diagram showing the rear projector 20 of the second embodiment in comparison with the rear projector 10 of the first embodiment.

FIG. 11 is an explanatory diagram showing a schematic configuration of a rear projector as a third embodiment.

FIG. 12 is a schematic plan view showing a main part of an optical system of a projection unit PJ ′ using a reflective liquid crystal panel as a light valve.

FIG. 13 is an explanatory diagram showing an example in which two projection light reflecting mirrors MR1 and MR2 are arranged in a projection lens.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Rear projector 20 ... Rear projector 30 ... Rear projector 100 ... Illumination optical system 110 ... Light source 120 ... Integrator optical system 130 ... Illumination light reflection mirror 140 ... Polarization conversion optical system 200 ... Color light separation optical system 200 '... Color light separation optical system 210, 220 ... dichroic mirror 210 ', 220' ... dichroic mirror 230 ... reflection mirror 240, 250 ... field lens 300 ... relay optical system 300 '... relay optical system 310 ... incident side lens 320, 340 ... relay reflection mirror 330 ... relay Lens 350: Exit lens (field lens) 400R, 400G, 400B: Light valve 410R, 410G, 410B: Signal input terminal 400R ', 400G', 400B ': Light valve 500: Cross dichroic Check prism 510: first dichroic surface 520: second dichroic surface 530: intersection line 550: first side surface (exit surface) 560: second side surface (first incident surface) 570: third side surface (first surface) No. 2 incident surface) 580 Fourth side surface (third incident surface) 600 Projection lens 600 ′ Projection lens 600 ″ Projection lens 700R, 700G, 700B Polarization beam splitter 710R, 710G, 710B Polarization separation Surface PJ: Projector PJ ': Projector MR1, MR2, MR3: Projection light reflection mirror SCR: Rear screen

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H088 EA14 HA13 HA20 HA21 HA24 HA28 MA06 MA20 2H091 FA05Z FA10X FA14Z FA26X FA41Z LA04 LA11 LA15 LA17

Claims (10)

[Claims] 1. A projector for displaying a substantially rectangular image on a projection surface as a projected image, comprising: three electro-optical devices for forming three color component images; A color combining means for combining the three color component images to form a color image, having two types of dichroic surfaces, and a projection lens for projecting the color image formed by the color combining means; The color synthesizing unit is arranged such that a direction of an intersecting line by the two types of dichroic surfaces is substantially parallel to a direction of a short side of the projection image, and each of the electro-optical devices includes: Among the three incident surfaces of the color synthesizing means, which have a substantially rectangular image forming area, and in which the direction of the long side of the image forming area coincides with the direction of the intersection, For each corresponding entrance surface The three electro-optical devices and the color synthesizing unit are arranged along a plane substantially perpendicular to a direction of a short side of the projection image, and the projector further includes: A projector provided with a plurality of mirrors for reflecting the color image formed by the color synthesizing means such that a direction of a long side of the color image formed by the means is directed to a direction of a long side of the projected image. 2. The projector according to claim 1, wherein the plurality of mirrors change a direction of a long side in a screen of the color image formed by the color combining unit into a long side in the screen of the projection image. A projector that has at least two mirrors that rotate at a predetermined angle so as to be oriented at a right angle, wherein the at least two mirrors are arranged such that normals passing through the centers of the respective reflection surfaces do not cross each other. . 3. The projector according to claim 2, wherein the predetermined angle is 90 degrees. 4. The projector according to claim 1, wherein at least one of the plurality of mirrors is disposed integrally with the projection lens. 5. The projector according to claim 4, wherein at least one mirror disposed integrally with the projection lens is configured by a total reflection prism. 6. The projector according to claim 1, wherein each of the three electro-optical devices has a signal input terminal on a side having a long side of the image forming area. 7. The projector according to claim 6, wherein the signal input terminal has a signal line formed to extend from a side having a long side to a side having a short side of the image forming area. The projector, wherein a part of the signal line is three-dimensionally bent such that the width of the signal line is reduced. 8. The projector according to claim 6, wherein an electro-optical device disposed on a first incident surface side parallel to an emission surface of the color synthesizing unit is a first electro-optical device. The electro-optical device disposed on the second incident surface side perpendicular to the first incident surface is referred to as a second electro-optical device, and the electro-optical device disposed on the third incident surface side parallel to the second incident surface. Third device
The signal input terminal of one of the first and second electro-optical devices is configured as a relay optical system disposed in an optical path of light for illuminating the second electro-optical device. A projector disposed in a space area surrounded by elements and the color synthesizing means. 9. The projector according to claim 6, wherein the three electro-optical devices are arranged on a first incident surface side parallel to an emission surface of the color synthesizing unit; An electro-optical device disposed on the second and third incident surfaces that are perpendicular to the first incident surface, and two types of electro-optical devices whose driving directions in the long side direction of each image forming area are opposite to each other. The projector that is configured. 10. The projector according to claim 6, wherein the three electro-optical devices are arranged on a first incident surface side parallel to an emission surface of the color combining unit.
And an electro-optical device disposed on a second incident surface side perpendicular to the first incident surface is referred to as a second electro-optical device, and a third incident light parallel to the second incident surface is provided. If the electro-optical device arranged on the surface side is a third electro-optical device,
The driving direction of the second electro-optical device in the long side direction of the image forming region is opposite to the first electro-optical device, and the driving direction of the third electro-optical device is in the short side direction of the image forming region. A projector comprising three types of electro-optical devices whose driving directions are opposite to the first electro-optical device.