JP2000122174A - Projection type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projection type display device which achieves the extreme reduction in the size of an occupied area and additional miniaturization by taking the arrangement of light valves into consideration in view of the fact that the shapes of the light valves are the same rectangular shapes as the shape of a projection screen. SOLUTION: This projection type display device is constituted to make color separation of light source light to first, second and third color light rays, to make the respective color rays incident on the light valves 11B, 11G, 11R arranged by each of the respective color light rays, to modulate and emit these light rays, to detect and take out the modulated light rays from the exit light rays, to color-synthesize the respective color detecting light rays by a cross dichroic prism 12 as a color synthesizing optical system, to make the synthesized light rays incident on a projection lens 13 and to project the light rays therefrom. The image forming parts of the light valves 11B, 11G, 11R have the rectangular shape. The cross dichroic prism 12 is constituted by orthogonally arranging two sheets of dichroic films 12a, 12b varying in characteristics and are arranged to align the intersection line of two sheets of the dichroic films 12a, 12b and the longitudinal direction of the image forming parts having the rectangular shape of the light valves 11B, 11G, 11R.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a projection display device that combines modulated light emitted from a plurality of liquid crystal light valves and projects the modulated light through a projection lens.

[0002]

2. Description of the Related Art Conventionally, light from a light source is separated into color lights having three wavelength ranges of R light, G light and B light, and each of the color lights is made incident on a liquid crystal light valve. As a projection type display device which modulates and emits the light, combines the emitted light by a color combining optical system, and projects a full-color image on a screen by a projection lens, FIG. The device according to 1 is known. This FIG. 1 will be described as a conventional example with reference to FIG.

That is, light emitted from a light source 101 is reflected by a dichroic mirror 105 having a B light reflection characteristic on the optical axis and reflected by a dichroic mirror 105 at right angles to the optical axis, G light transmitted through the light as it is, First, color separation is performed with the B light. The B light is further incident on and reflected by the reflection bending mirror 107, and is incident on the B light liquid crystal light valve 108B.

[0004] The R and G light further travels and is incident on a dichroic mirror 106 having a G light reflection characteristic and arranged in parallel with the dichroic mirror 105, and transmits through the G light reflected by the mirror 106 and the G light. It is color-separated into traveling R light.

That is, the dichroic mirror 105 and the mirror 106 arranged in parallel on the optical axis constitute a “color separation optical system”.

The color-separated G light enters a liquid crystal light valve 108G for G light, and the R light enters a light valve 108R for R light via two folding mirrors 107. Each color light incident on the light valves 108B, 108G, 108R is modulated by a color signal of each color and emitted, and is incident on a cross dichroic prism 109 constituting a color combining optical system.

This cross dichroic prism 109
Is a dichroic film 11 having R light reflection characteristics inside.
This is a prism in which dichroic films 111 having 0 and B light reflection characteristics are arranged in an X shape so as to be perpendicular to each other.

[0008] The cross dichroic prism 109
The light combined by the above is incident on the projection lens 112 and projected on a screen (not shown).

Further, FIG. 7 shows Fi of the above-mentioned US patent.
g. A cross dichroic prism 109 constituting the color synthesizing optical system described as 3 and a liquid crystal light valve 108 for each color light disposed near the incident surface thereof
B, 108G, 108R and each light valve 108B,
Perspective explanatory diagrams describing the states of images on 108G and 108R are described.

[0010]

However, in the reflection type display device described in the above-mentioned conventional example, it is necessary to arrange each member shown in FIG. 6 in a housing to constitute a projection type display device. As can be understood from FIGS. 6 and 7, the image projected on the screen and the light valve 108 are displayed.
If the device is arranged on the desk from the arrangement of B, 108G, and 108R, the configuration diagram of FIG. 6 must be a diagram viewed from the top of the desk, and as a result, this projection display device Has to be a device having a predetermined thickness and a considerable area in plan.

As described above, the liquid crystal light valve 108B,
In a projection type display device using 108G and 108R, it is desired to further reduce the size of the device. In particular, when a presentation at a conference or the like is desired to be performed by the device, the output of a small computer is announced. It is also conceivable that the projector is operated by the user himself, and the demand for ease of installation, transportation, etc. is increasing, and conventional devices cannot be satisfied even in consideration of the occupied area. Was.

In view of the fact that the shape of the light valve is the same rectangle as that of the projection screen, the present inventors consider the arrangement of the light valve, thereby significantly reducing the occupied area and reducing the size. It was done to achieve the change.

[0013]

According to a first aspect of the present invention, there is provided:
The light source light is color-separated into first, second, and third color lights, incident on light valves arranged for each color light, modulated, and emitted. Modulated light is analyzed and extracted from the emitted light, and each color analysis is performed. In a projection display device having a configuration in which light is color-combined by a color-combining optical system to be incident on a projection lens and projected, the light valve has an image forming unit having a rectangular shape, and the color-combining optical system includes: Two dichroic films having different characteristics are arranged orthogonally, and the intersection of the two dichroic films is aligned with the longitudinal direction of the rectangular image forming portion of the light valve. It is a projection type display device.

According to a second aspect, the projection type display device according to the first aspect, wherein the color synthesizing optical system comprises a cross dichroic prism.

According to a third aspect, the light source light is separated into first, second and third color lights, incident on light valves arranged for each color light, modulated and emitted, and modulated light is emitted from the emitted light. In the projection type display device configured to analyze and take out the respective color analysis lights by the color synthesis optical system, and to make the light incident on the projection lens and project the light, the three light valves have an image forming unit. A projection display device having a rectangular shape, and wherein an image formed on one of the three light valves is an image which is inverted upside down with respect to the images on the other two light valves. It is assumed that.

According to a fourth aspect, the light from the light source is polarized and separated by a polarization beam splitter, and one of the polarized lights is divided into first, second and third light by a color separation / combination prism comprising a plurality of prisms.
The light is then separated into light beams of different colors, incident on the light valves for each color light, modulated, the emitted light is subjected to color synthesis by the color separation / combination prism, and the combined light is analyzed and extracted by the polarization beam splitter. A projection type display device for projecting the analysis light by a projection lens, wherein the light valve has a rectangular image forming unit, and a surface on which a polarization separation unit of the polarization beam splitter is formed; The projection type display device is arranged in parallel with the longitudinal direction.

According to a fifth aspect, among the members constituting the projection type display device according to any one of claims 1 to 4, at least members other than the projection lens are arranged in a housing. The projection type display device has a carrying handle on the upper part of the housing.

[0018]

Embodiments of the present invention will be described below.

[First Embodiment of the Invention]

The projection display device according to the first embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a perspective view showing the configuration of a projection type display device according to the present invention. For convenience of explanation, coordinate axes X, Y, and Z orthogonal to each other are defined as shown.

The basic structure and components of the projection display device will be described with reference to FIG. The configuration diagram shown in FIG. 2 is viewed from the Y-axis direction in FIG. 1 in the −Y direction.

In the figure, reference numeral 1 denotes a light source, which comprises a lamp 1a and a concave mirror 1b, for example, a parabolic mirror. The substantially parallel light source light emitted from the light source 1 is:
The light is incident on a first fly-eye lens plate 2 in which a plurality of lenses 2a are arranged in a plane. The light from the light source passing through the lens plate 2 is incident on a second fly-eye lens plate 4 in which a plurality of lenses 4a are arranged on the surface via a bent reflection mirror 3 also serving as an ultraviolet cut filter.

Here, the first and second fly-eye lens plates 2 and 4 will be described. The outer shape of each lens 2a constituting the first fly-eye lens plate 2 is a rectangular shape obtained by proportionally reducing the outer shape of light valves 11B, 11G, and 11R, which will be described later.
The light is decomposed into a plurality of light beams by an opening determined by the external shape.

In the present embodiment, the number of lenses 2a of the first fly-eye lens plate 2 is 5 × 4, that is, a total of 20 arrays. Further, the second fly-eye lens plate 4 is configured to be disposed at the focal position of the lens 2a of the first fly-eye lens plate 2, and the lens 4a of the second fly-eye lens plate 4 is
Similarly, a total of 20 5 × 4 lenses are arranged, and as described above, the lens 2 a of the first fly-eye lens plate 2,
The lens 4a of the second fly-eye lens plate 4 has a one-to-one correspondence, and the lens 4a is arranged at the focal position of the corresponding lens 2a.

Due to the above arrangement, the light source light incident on the individual lenses 2a of the first fly-eye lens plate 2 is condensed on the lens 4a of the second fly-eye lens plate 4 to form a bright spot. It is formed on the lens 4a.

In contrast to the lens 4a of the second fly-eye lens plate 4, the lens 2a of the first fly-eye lens plate 2 and the light valves 11B, 11G,
11R is designed and manufactured in such a manner that each lens 4a has a conjugate relationship, and the number of light valves 11B, 11 is equal to the number of lenses 4a of the second fly-eye lens plate 4.
By performing superimposed critical illumination on G, 11R, uniform illumination on the image forming units of the light valves 11B, 11G, 11R can be achieved. In addition, the lenses 2a of the first fly-eye lens plate 2 are light valves 11B, 11G, 1
Since the illumination light flux on the light valves 11B, 11G, and 11R has the same rectangular shape as the outer shape of the image forming unit of 1R, the image forming units of the light valves 11B, 11G, and 11R are illuminated without waste, and The configuration is such that no unnecessary illumination is performed on the section.

The light from the light source passing through the second fly-eye lens plate 4 is incident on a cross dichroic mirror 15 in which the B light reflecting dichroic mirror 6 and the R and G light reflecting dichroic mirrors 5 are arranged in an X-shape so as to be orthogonal to each other. The B light and the G and R lights are reflected by the mirrors 5 and 6 in directions opposite to each other and perpendicular to the incident optical axis.

The R and G lights further enter the G light reflecting dichroic mirror 9 disposed on the optical axis via the bending mirror 7, and are reflected at right angles to the incident optical axis and travel along with the G light. Separated into light.

The cross dichroic mirror 15 thus constituted by the dichroic mirror 5 and the mirror 6
And the dichroic mirror 9 constitute a “color separation optical system” that separates the light into three colors.

The B light incident on the cross dichroic mirror 15 and reflected by the dichroic mirror 6 constituting the cross dichroic mirror 15 is
The reflected light travels in the direction, travels through the bending mirror 8, travels in the X direction, and enters the polarization beam splitter 10B arranged on the optical axis for B light.

Further, the G light, which is the R and G light incident on the dichroic mirror 9 and is color-separated as reflected light by the mirror 9, is a G light polarizing beam splitter 10G.
The R light that has been color-separated as transmitted light is incident on the R light polarizing beam splitter 10R.

The polarization beam splitters 10B, 10 for each color
The light valves 11B, 11G, and 11R, in which the S-polarized light emitted from the polarization beam splitters 10B, 10G, and 10R are emitted and reflected on the optical axis for each color light, respectively, are input to the G and 10R. As illumination light.

In the prior art, a transmission type liquid crystal light valve was used, but in the present embodiment, reflection type liquid crystal light valves 11B, 11G, 11R were used. As the reflection type light valves 11B, 11G, and 11R, an electric writing type and an optical writing type are known as image signal writing systems. In the present embodiment, the electric writing type is used. The optical writing system requires a writing optical system, whereas the electric writing system does not require it, which is advantageous in terms of miniaturization. Further, the electric writing type reflective light valves 11B, 11G, and 11R perform selection of modulation or non-modulation of a pixel by an image signal by switching with a non-linear element such as a TFT, as compared with the transmission light valve of the conventional example. Since the element can be disposed below the reflective layer of the pixel and is not disposed at the corner of the pixel as in the transmissive type, it is advantageous in terms of aperture ratio and increases the brightness of the projected image. This is advantageous in that respect.

Then, the reflection type light valve 11 for each color is used.
Light emitted from B, 11G, and 11R is a mixed light including modulated light (P-polarized light) and unmodulated light (S-polarized light), and the emitted light is a polarized beam splitter 10B, 1 for each color light.
Light that is incident on the polarization beam splitters 10B, 10G, and 10R again when the light is incident on the polarization beams splitters 10B, 10G, and 10R is extracted as analysis light (P-polarized light), and each color is transmitted to the cross dichroic prism 12 that forms a color combining optical system. Are made to enter from different incident surfaces to achieve color composition, and are emitted as combined light in the X direction.

The cross dichroic prism 12 is an X-shaped prism in which the R light reflecting dichroic film 12a and the B light reflecting dichroic film 12b are orthogonal to each other.
12b reflects the B light and the R light in the X direction,
In addition, color synthesis is achieved by transmitting the G light through both dichroic films 12a and 12b and similarly emitting it in the X direction.

The projected combined light emitted after the color combining is achieved by the cross dichroic prism 12 is incident on a projection lens 13 and projected on a screen (not shown) as a full-color image.

As described above, it can be understood that the components constituting the basic configuration of the projection type display device of the present embodiment are basically arranged in a plane on the XZ plane.

Now, the projection type display device having the above-described basic configuration is arranged as a projection device on the housing 20. The arrangement is as shown in FIG. 1 and the Z direction is the upper part. It has the characteristic.

That is, the housing 20 in which the constituent members are arranged
Has a rectangular parallelepiped box shape, and the Z direction in FIG. 2 and the height direction (Z direction) in FIG.

Next, each of the light valves 11B, 11G, 1
The arrangement of the 1R, the polarization beam splitters 10B, 10G, 10R and the cross dichroic prism 12 (color combining optical system) will be described in detail again.

FIG. 3 is an enlarged perspective view of these components including the projection lens 13. The projected image is usually in the shape of a horizontally long rectangle, and its shape is light valves 11B, 11G, and 11R.
Are enlarged and projected by the projection lens 13 of the image forming section of FIG. For this purpose, the light valves 11B, 11
The G and 11R image forming portions have a rectangular shape, and the first and second fly-eye lens plates 2 and 4 are used to efficiently illuminate the image forming portion with illumination light in a rectangular shape and uniformly.
Illumination using is as described above.

In the projection type display device of the present invention shown in FIG. 3, the arrangement of each light valve 11B, 11G, 11R is determined by the rectangular longitudinal direction (lateral direction) and the direction parallel to the Y axis in FIG. It is necessary to arrange the cross dichroic prism 12 constituting the color synthesizing optical system so as to coincide with the direction of the intersecting lines orthogonal to each other.

Assuming that the image projected by the projection display device is projected in the X direction with the projection display device shown in FIG. 1 on a table having an XY plane as it is, the images of the light valves 11B, 11G, and 11R are obtained. The image on the forming unit is shown in FIG.
It is as shown in. However, the light valves 11G and 11R are images (shown by solid lines) viewed from the incident and exit surfaces. Comparing these image-formed projection images on the respective light valves 11B, 11G, 11R, it can be seen that the light valve 11B and the light valve 11R and the light valve 11G have inverted vertical relations. It can be understood.

Next, each of the light valves 11B, 11G, 1
Considering the reflected light emitted from the light valve 1R, the modulated light component of the light emitted from each of the light valves 11B, 11G, and 11R is a polarization beam splitter 10B, 10G, 10R,
Projection lens 1 through cross dichroic prism 12
3 and is projected on the screen. The projected image on the screen and each light valve 11B, 11G, 1
1R, the projection lens 1
The light beam having the NA (numerical aperture) determined by N.3 is incident on the projection lens 13 as a divergent light beam having the NA from each point on each light valve image forming unit, but the polarization beam splitters 10B and 10G. , 10R and the cross dichroic prism 12 need to allow all the light beams having the NA to pass therethrough, so that both the polarizing beam splitters 10B, 10G, 10R and the cross dichroic prism 12 are viewed in the X direction from the back of the light valve 11G, for example. The vertical and horizontal lengths of both members need to be larger than the vertical and horizontal lengths of the light valve 11G.

However, in the case of the present invention, the short direction (vertical direction) of the light valve 11G is arranged in the Z direction, and the short direction (longitudinal direction) of the light valves 11R and 11B is arranged in the X direction. Beam splitter 10R,
The length in the X direction and the Z direction of 10B and the length in the short direction (vertical direction) of each light valve can be only the length in consideration of the NA. Further, for the same reason, the X (Z) direction of the cross dichroic prism 12 can also be set to the minimum length.

The above description is based on the cross dichroic prism 12, the polarization beam splitter 10B, and the cross dichroic prism 12 shown in FIG.
The analysis and synthesis optical system including 10G and 10R is set to the minimum value of the side length of the square shape of the cross-sectional shape obtained by cutting the polarization separation plane and the plane (XZ plane) perpendicular to the dichroic films 12a and 12b. And the miniaturization of the polarizing beam splitters 10B, 10G, 10R and the cross dichroic prism 12 can be achieved.
As a result, the size and weight of the projection display device can be reduced.

Further, as shown in the configuration of the projection type display device shown in FIG. 1, other components except the projection lens 13 are arranged in a box-shaped housing 20. It can be in the form of a projection display device in which a carrying handle is attached to a surface. If the projection display device is carried with the handle, it can be carried as if it were a bag. Then, when brought to a meeting place as it is and used as it is on a desk, it becomes a projection type display device most suitable for presentation.

In the embodiment of the present invention described above, a reflection type light valve is used as the light valves 11B, 11G and 11R in consideration of the point of increasing the brightness of the projected image. Of course, a valve may be used.

At this time, a plurality of light valves 1 are arranged close to the cross dichroic prism 12 of the color combining optical system.
1B, 11G, and 11R are arranged. However, since the above discussion of NA is applied to the dichroic prism 12, the members can be downsized, which can contribute to downsizing of the device.

Further, in the projection type display device described above, each of the light valves 11B, 11G, 11R
Although the cross dichroic prism 12 is used as the “color combining optical system” of the modulated light that has been detected, the member used as the optical system is not limited to this. That is, a cross dichroic mirror in which two dichroic mirrors having different characteristics are arranged in a cross shape may be used.
A configuration in which two mirrors are arranged in parallel on the optical axis may be adopted. In any case, the size of the member can be reduced, and the same effect can be obtained.

[Embodiment 2] A projection display apparatus according to Embodiment 2 of the present invention will be described with reference to FIGS.

FIG. 4 is a perspective view showing the configuration of a projection type display device according to the present invention. Note that, for convenience of explanation, coordinate axes X, Y, Z are defined as shown in the drawing, as in the previous embodiment.

The light source 21, the first fly-eye lens plate 22, the reflection mirror 23, and the second fly-eye lens plate 24 indicated by reference numerals 21 to 24 have the same members and functions as those in the previous embodiment, respectively. Here, the description is omitted. In the present embodiment, the shape of the lens 22a of the first lens plate 22 and the shape of the lens 24a of the second lens plate 24 are different because the optical path lengths to the light valves 29B, 29G, and 29R are different from the previous embodiment. Become. This is for efficiently superimposing the light valves 29B, 29G, and 29R.

The light emitted from the second fly-eye lens plate 24 enters the polarization beam splitter 25, and the P-polarized light that is transmitted and discarded by the polarization separation unit 25p of the polarization beam splitter 25 and the reflected S-polarized light are reflected. It is polarized and separated into polarized light. The S-polarized light enters a color separation / combination prism composed of prisms 26, 27 and 28, and is subjected to a color separation action.
Decomposed into B, G, R light. First, the incident surface 1 of the prism 26
The S-polarized light incident from 6-1 proceeds through the prism as it is, enters the B light reflecting dichroic film formed on the 26-2 surface of the prism 26, and is reflected by the film.
The light is color-separated into light and R and G light that travels as it is and enters from the entrance surface 27-1 of the prism 27 that is arranged with a gap therebetween.

The B light travels through the prism 26, travels under the total reflection at the entrance surface 26-1, and exits from the exit surface 26-3, and is a reflection type light disposed near the exit surface. The light enters the valve 29B.

The R and G light incident on the prism 27 proceeds as it is, and the surface 27-2 of the prism 27 and the prism 28
The R light is reflected by the R light reflecting dichroic film formed on the joining surface of the surface 28-1, and proceeds through the prism 27 as it is, and is reflected by the entrance surface 27-2 of the prism 27.
The light proceeds and is emitted from the emission surface 27-3 and is incident on the R light light valve 29R.

On the other hand, the G light transmitted through the dichroic film travels in the prism 28 and is totally reflected on the surface 28-2.
Proceeds and is emitted from the emission surface 28-3, and the light valve 2
It is incident on 9G.

Each color light incident on the light valves 29B, 29G, 29R is modulated by the color signal of each color light in each light valve 29B, 29G, 29R, and emitted as a mixed light of modulated light and non-modulated light. The light travels again in the direction opposite to the incident optical axis, and is incident from the exit surface.

Each of the color lights incident on the prisms 26, 27, and 28 travels in the opposite direction, and color synthesis is achieved by each dichroic film.
The light is emitted as color-combined light from the surface 6-1. The emitted light is a mixture of P-polarized light as modulated light and S-polarized light as unmodulated light.

The combined light exiting the prism 26 is incident on the polarization beam splitter 25, where the polarization splitter 25p detects the modulated light as transmitted light and discards the unmodulated light as reflected light.

The analysis light is incident on the projection lens 30,
A full-color image is projected on a screen (not shown).

In the projection type display device according to this embodiment, each component is basically arranged on the XZ plane. Further, the constituent members are arranged in the housing 31 as shown in FIG. 4, and the housing has a rectangular parallelepiped box shape, and the Z direction in FIG. 5 matches the height direction in FIG. That is.

Next, the light valves 29B, 29G, 2
9R, as in the previous embodiment, the pixel forming portion has a rectangular shape, and the pixel forming portion has a projected image on the screen (see FIG. 4).
The projection image is a plane parallel to the YZ plane, and the projected image is projected as a rectangular shape in which the vertical direction of the image is shorter than the Y direction, that is, the horizontal direction of the image. But light valves 29B, 29G, 29
The rectangular longitudinal direction of the R pixel forming portion is formed so as to be parallel to the surface formed by the polarization splitting portion 25p of the polarization beam splitter 25 and the surface formed by the dichroic film for color separation / synthesis in the composite prism. .

Also in this embodiment, for the same reason as in the previous embodiment, the polarizing beam splitter 25 and the prisms 26, 27, and 28 constituting the composite prism have the minimum size in the cross-sectional shape cut parallel to the XZ plane. The effect that can be achieved.

The shape of the image of the image forming section of the light valves 29B, 29G and 29R is a vertically inverted image of that of the light valves 29B and 29R and that of the light valve 29G. This is because the light emitted from the light valves 29B and 29R is subjected to a total of two reflections by the dichroic film and the total reflection, whereas the light emitted from the light valve 29G is subjected to the reflection only by the total reflection.

Further, similarly to the previous embodiment, by attaching a carrying handle on the upper surface of the housing 31, it is possible to carry like a bag.

[0068]

As described above, according to the projection display apparatus of the present invention, the size of the apparatus can be reduced, and the occupied area can be reduced. If a handle is attached to the housing, it can be carried like a bag.

[Brief description of the drawings]

FIG. 1 is a perspective configuration diagram of a projection display device according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a basic configuration of a projection display device according to Embodiment 1 of the present invention.

FIG. 3 is a detailed perspective view illustrating a light valve, an analysis optical system, a color combining optical system, and a projection lens of the projection display device according to the first embodiment of the present invention.

FIG. 4 is a perspective configuration diagram of a projection display device according to a second embodiment of the present invention.

FIG. 5 is a side view of the projection display device according to the second embodiment of the present invention.

FIG. 6 is an explanatory sectional view of a conventional projection display device.

FIG. 7 is a detailed perspective view illustrating a synthetic optical system and the like of a conventional projection display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light source 2 1st fly-eye lens plate 3 Bend reflection mirror 4 2nd fly-eye lens plate 5, 6, 9 Dichroic mirror 7, 8 Bend mirror 10R, 10G, 10B Polarization beam splitter 11R, 11G, 11B Reflection type light Valve 12 Cross dichroic prism (color synthesis optical system) 15 Cross dichroic mirror (color separation optical system) 20 Housing

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Naoo Ozeki 3-2-2, Marunouchi, Chiyoda-ku, Tokyo Nikon Corporation (72) Inventor Masatoshi Sato 2-3-2, Marunouchi, Chiyoda-ku, Tokyo Nikon Corporation (72) Inventor Yuji Mabe 3-2-3 Marunouchi, Chiyoda-ku, Tokyo Nikon Corporation

Claims (5)

[Claims] 1. A light source light is color-separated into first, second, and third color lights, incident on a light valve arranged for each color light, modulated, and emitted, and modulated light is detected from the emitted light. The light valve has a rectangular image forming section, wherein the image forming section has a rectangular shape. The synthetic optical system is configured by two dichroic films having different characteristics being arranged orthogonally to each other. The intersection line of the two dichroic films and the longitudinal direction of the rectangular image forming unit of the light valve. A projection type display device, wherein 2. The projection type display device according to claim 1, wherein said color synthesizing optical system comprises a cross dichroic prism. 3. The light source light is color-separated into first, second and third color lights, incident on a light valve arranged for each color light, modulated and emitted, and modulated light is detected from the emitted light. In the projection display device, the color analysis light is combined by a color combining optical system, and the combined light is incident on a projection lens and projected, wherein the three light valves have a rectangular image forming portion. Further, an image formed on one of the three light valves is an image inverted upside down with respect to the images on the other two light valves. apparatus. 4. A light source light is polarized and separated by a polarization beam splitter, and one of the polarized lights is color-separated into first, second and third color lights by a color separation / combination prism comprising a plurality of prisms. The light enters the light valve, is modulated, the emitted light is subjected to color synthesis by the color separation / combination prism, and the combined light is analyzed and extracted by the polarization beam splitter, and the analysis light is transmitted to the projection lens. In the projection display device, the image forming unit has a rectangular shape, and a surface forming a polarization splitting unit of the polarization beam splitter and a longitudinal direction of the light valve are arranged in parallel. A projection type display device characterized by the above-mentioned. 5. A projection type display device according to claim 1, wherein at least members other than the projection lens are arranged in a housing, and furthermore, an upper portion of the housing is provided. , A projection display device having a handle for transportation.