JPH10186546A - Liquid crystal projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent hot blast from adversely influencing the periphery and to display a picture without fluctuation by arranging a ventilating fan proximately to a projection lens so that the fan may be inclined to the optical axis direction of the projection lens. SOLUTION: In order to prevent heat generated from a light source from exerting an influence on component parts other than the light source, the ventilating fan for cooling the light source 38 is arranged near a metal halide lamp 1 being the light source and lamp reflectors 3 and 5 so as to discharge the hot blast 39 to the outside of the housing of the liquid crystal projector. The fan 38 is arranged adjacently to the projection lens 37 to be inclined so that exhaust air 39 from the fan 38 may go away from the projected light 36 from the lens 37. The inclination angle of the fan 38 is set to b=15 deg. with reference to the angle a=30 deg. of the projection light 36a of the projected light 36 on the exhaust air 39 side so as to prevent a situation that the hot blast 39 exhausted from the fan 38 flows into the projected light 36 from the lens 37 and the projected picture to a screen is fluctuated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal projector which irradiates a liquid crystal panel with light from a light source, projects the light emitted from the liquid crystal panel onto a screen by a projection lens, and displays an image.

[0002]

2. Description of the Related Art Conventionally, as a liquid crystal projector using a transmission type liquid crystal panel of this kind, for example, Japanese Patent Application Laid-Open No. 63-21 / 1988
No. 6026 is disclosed. In this conventional configuration,
Light source (reference numeral 21), first reflecting mirror (23), first dichroic mirror (26), second reflecting mirror (3)
0), a second dichroic mirror (27), a third reflecting mirror (28), a fourth reflecting mirror (29), a first transmissive liquid crystal panel (33), a second transmissive liquid crystal panel (39), a third transmissive liquid crystal panel (45), a dichroic prism (49), and a projection lens (50), and illuminating light from a light source is passed through a first reflecting mirror to a first dichroic mirror. Irradiates the first liquid crystal panel through the second reflecting mirror with the first outgoing light that has been color-separated by the first dichroic mirror, and the second liquid crystal panel that has been color-separated by the first dichroic mirror. The outgoing light is made incident on the second dichroic mirror, the first outgoing light color-separated by the second dichroic mirror is made incident on the second liquid crystal panel, and the first light is color-separated by the second dichroic mirror. The second emitted light is radiated to the third liquid crystal panel via the third reflection mirror and the fourth reflection mirror, and the transmitted light from the first liquid crystal panel, the transmitted light from the second liquid crystal panel, The transmitted light from the third liquid crystal panel is color-combined by a dichroic prism, and the color-combined emitted light is projected onto a screen by a projection lens.

[0003] Further, as disclosed in Japanese Patent Application Laid-Open No. Hei 3-10218, an exhaust fan (15, 27) for cooling a light source is provided.

[0004] Furthermore, for example, JAPAN OPTICS '94 Optical Alliance Symposium Hamamatsu '94 (p135-p136) sponsored by the Optical Society of Japan (Reaction Society of Japan).
U.S. Pat. No. 22, Fa06, entitled "High-efficiency illumination optical system for liquid crystal projector using deformed aperture lens array", uses a metal halide lamp and a parabolic mirror as a light source, and
A device provided with a V-IR cut filter, a first lens array, and a second lens array is known.

A liquid crystal projector having a configuration in which the above three known examples are combined has been put to practical use.

Hereinafter, a liquid crystal projector in which this conventional technique is combined will be described with reference to the drawings.

FIG. 6 is a top view of a liquid crystal projector optical system in which the prior art is combined.

An illumination light 51 from a metal halide lamp 50 as a light source is supplied to a lamp reflector 52 of a parabolic mirror, U
V-IR cut filter 53, first lens array 5
4. Cold mirror 55, which is the first reflecting mirror, second
A dichroic mirror 57 for transmitting R-color light and reflecting G and B light, which is a first dichroic mirror, transmits R-light 58, and transmits G and B light 5 as a first dichroic mirror.
9 is reflected.

The R-color light 58 is reflected by a reflection-enhancing aluminum mirror 60 as a second reflection mirror, and
1. Through a polarizing plate 62, the light enters a liquid crystal panel 63 for R color light, which is a first transmission type liquid crystal panel.

The G and B color lights 59 are incident on a dichroic mirror 64 that is a second dichroic mirror that reflects G color light and transmits B color light, where the G color light 65 is reflected and the B color light 6 is reflected.
6 is transmitted. The G color light 65 passes through a condenser lens 67,
The light enters a liquid crystal panel for G color light 69 which is a second transmission type liquid crystal panel via a polarizing plate 68.

The B-color light 66 is transmitted from a relay lens 70, a third reflection mirror, an increased reflection aluminum mirror 71, a relay lens 72, and a fourth reflection mirror, an increased reflection aluminum mirror 7.
3, via the condenser lens 74 and the polarizing plate 75,
To the liquid crystal panel 76 for B color light, which is a transmission type liquid crystal panel.

The R transmitted light 77 from the liquid crystal panel 63, the G transmitted light 78 from the liquid crystal panel 69, and the B transmitted light 79 from the liquid crystal panel 76 are color-combined by a dichroic prism 80, and the emitted light is color-combined. 81 to projection lens 8
2 project onto a screen (not shown).

An exhaust fan 83 for cooling the light source is arranged in the vicinity of the metal halide lamp 50 and the lamp reflector 52 so as to prevent the heat generated from the light source having a high temperature from affecting the components. Then, the hot air 84 is exhausted outside the housing (not shown) of the liquid crystal projector.

According to the liquid crystal projector having this configuration, a bright, large-screen image can be obtained on the screen while cooling the light source that becomes high in temperature.

However, in the conventional liquid crystal projector having this configuration, the hot air 84 exhausted by the exhaust fan 83 may flow in the direction of a viewer located near the liquid crystal projector, which makes the viewer uncomfortable. There was a problem that would give.

The liquid crystal projector may be used with video equipment such as a personal computer placed in the vicinity, but care must be taken to place such heat-sensitive equipment in a position where it is not exposed to hot air. In addition, in order to efficiently exhaust the heat generated from the light source, it is necessary to take care not to place an object that blocks the exhaust at the position where the hot air is exhausted, which poses a problem in terms of usability. Was.

On the other hand, for example, Japanese Utility Model Laid-Open No. 5-5942.
As disclosed in Japanese Patent Laid-Open Publication No. 4 (1994), an exhaust fan for cooling the light source is arranged on the same surface as the surface on which the front tube portion of the projection lens is arranged, and the projection direction and the exhaust direction are set to the same direction. A configuration has been proposed. According to this, the hot air exhausted from the exhaust fan does not flow in the direction of the viewer located near the liquid crystal projector, and the viewer does not feel uncomfortable. In addition, there is no need to consider when placing heat-sensitive devices near the liquid crystal projector, and there is no need to consider placing objects that block the exhaust at locations where hot air is exhausted. A liquid crystal projector is obtained. However, in this prior art, no consideration has been given to measures such as the fact that the hot air from the exhaust fan flows in the projection light from the projection lens and the projected image on the screen may fluctuate. Also, there was no particular consideration on the configuration for more efficiently exhausting hot air. Also, no consideration was given to the configuration of the optical system including the first lens array and the second lens array.

[0018]

SUMMARY OF THE INVENTION It is an object of the present invention to display an image with no fluctuation on a screen without the adverse effect of hot air exhausted from an exhaust fan on viewers and devices arranged in the vicinity. Another object of the present invention is to provide a high-performance and easy-to-use liquid crystal projector capable of efficiently exhausting air in the apparatus for cooling.

[0019]

According to the present invention, there is provided a liquid crystal projector which irradiates a liquid crystal panel with light from a light source and projects light emitted from the liquid crystal panel onto a screen by a projection lens. (1) An exhaust fan for exhausting the air inside the apparatus to the outside is arranged close to the projection lens, and is arranged so as to be inclined with respect to the optical axis of the projection lens so that the exhaust flow is away from the projection light of the projection lens. .

(2) A wind direction plate is provided so as to be inclined with respect to the optical axis direction of the projection lens so that the exhaust flow of the exhaust fan moves away from the projection light of the projection lens.

(3) The exhaust flow of the exhaust fan is arranged obliquely with respect to the direction of the optical axis of the projection lens so as to keep away from the projection light of the projection lens, and the inclination angle of the one near the projection lens and the side far from the projection lens. And a plurality of wind direction plates having different inclination angles.

(4) The exhaust flow of the exhaust fan is arranged so as to be inclined with respect to the optical axis direction of the projection lens so as to keep away from the projection light of the projection lens, and the inclination angle of the one closer to the projection lens is farther from the projection lens. A plurality of wind direction plates having a larger inclination angle than that of the side.

(5) Light from a light source is made incident on a first dichroic mirror via a first lens array, a first reflection mirror, and a second lens array, and color separation is performed by the first dichroic mirror. The first emitted light is
Irradiates the first liquid crystal panel through the reflection mirror of
The second outgoing light color-separated by the dichroic mirror is incident on a second dichroic mirror, and the first outgoing light color-separated by the second dichroic mirror is incident on a second liquid crystal panel. The second liquid crystal panel is irradiated with the second emission light color-separated by the second dichroic mirror via the third reflection mirror and the fourth reflection mirror, and transmitted light from the first liquid crystal panel, This is a liquid crystal projector that colors transmitted light from the second liquid crystal panel and transmitted light from the third liquid crystal panel by a dichroic prism, and projects the combined light on a screen by a projection lens. Thus, the first reflecting mirror, the second lens array, the first dichroic mirror, the second dichroic mirror, and the third reflecting mirror are arranged in this order. And a first reflecting mirror, a first lens array, a light source, and an exhaust fan are arranged in this order, and the arrangement of the first reflecting mirror, the first lens array, the light source, and the exhaust fan is a projection lens, a dichroic prism. ,
The second dichroic mirror is arranged substantially parallel to and adjacent to the arrangement of the second dichroic mirror.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a first embodiment of the present invention, and is a top view of a liquid crystal projector optical system.

Illumination light 2 from a metal halide lamp 1 as a light source passes through a lamp reflector 3 of an ellipsoidal mirror.
The light enters the first lens array 4. Here, the lamp reflector 5 of the spherical mirror is provided for the purpose of returning the previously unused illumination light 6 from the metal halide lamp 1 to the metal halide lamp 1 to reuse the light. The first lens array 4 has a light incident surface 7 having a concave lens surface, and a convergent light 8 from a lamp reflector 3 of an ellipsoidal mirror.
Has the effect of converting the
The lens array can be downsized.

The light 9 emitted from the first lens array 4 is provided by a first reflection mirror, a reflection-enhancing silver mirror 10, a second lens array 11, a first dichroic mirror, B-color light reflection, and G and R color light transmission. , The B color light 13 is reflected, and the G and R color lights 14 are transmitted. The B-color light 13 is reflected by a reflection-enhancing aluminum mirror 15 which is a second reflection mirror, and a condenser lens 16,
The light enters a B-color light liquid crystal panel 18 as a first transmission type liquid crystal panel via a polarizing plate 17. G and R color light 14
Is a second dichroic mirror, G color light reflection, R
The light enters the dichroic mirror 19 that transmits color light, the G light 20 is reflected, and the R light 21 is transmitted. The G light 20
Through a condenser lens 22 and a polarizing plate 23, the light enters a liquid crystal panel 24 for G color light, which is a second transmission type liquid crystal panel. The R-color light 21 passes through a relay lens 25, a cold mirror 26 that transmits infrared rays as a third reflection mirror, a relay lens 27, an increased reflection silver mirror 28 as a fourth reflection mirror, a condenser lens 29, and a polarizing plate 30. And a liquid crystal panel for R color light 31 which is a third transmission type liquid crystal panel.
Incident on.

The B transmitted light 32 from the liquid crystal panel 18, the G transmitted light 33 from the liquid crystal panel 24, and the R transmitted light 34 from the liquid crystal panel 31 are color-combined by a dichroic prism 35, and the color-combined emission light. 36 is the projection lens 3
7, the image is projected on a screen (not shown).

In order to prevent heat generated from the light source having a high temperature from affecting components other than the light source, exhaust for cooling the light source is provided in the vicinity of the metal halide lamp 1, the lamp reflector 3 and the lamp reflector 5, which are light sources. Fan 38
Are arranged, and the hot air 39 is exhausted outside the housing of the liquid crystal projector. The exhaust fan 38 is arranged adjacent to the projection lens 37, and the exhaust fan 38 is inclined so that the exhaust air 39 of the exhaust fan 38 moves away from the projection light 36 of the projection lens 37. The inclination angle b of the exhaust fan is set to 15 ° with respect to the angle a = 30 ° of the projection light 36a on the exhaust air 39 side of the projection light 36, and the exhaust fan 38 is included in the projection light 36 from the projection lens 37. Hot air exhausted from
To prevent the projected image on the screen from fluctuating.

Further, an exhaust fan 38 is arranged adjacent to the projection lens 37, and a plurality of wind direction plates 40 are arranged obliquely so that the exhaust air 39 of the exhaust fan 38 moves away from the projection light 36 of the projection lens 37. And the projection lens 3
The inclination angle c of the wind direction plate 40a closer to 7 is greater than the inclination angle d of the wind direction plate 40b farther from the projection lens 37. For example, the inclination angle c = 30 °, the inclination angle d
= 15 °. The angle a of the projection light 36a on the exhaust air 39 side of the projection light 36 is set to be approximately equal to the inclination angle c = 30 ° of the wind direction plate 40a on the side closer to the projection lens 37. It is possible to reduce the fluctuation of the projected image on the screen due to the flow of the discarded hot air 39a from the exhaust fan 38 in the projection light 36 from the camera. Further, with respect to the inclination angle b of the blower fan 38 = 15 °, the inclination angle d of the wind direction plate 40b farther from the projection lens 37 =
Since the angle is set to be substantially equal to 15 °, the path of the hot air 39 is not greatly bent by the wind direction plate 40b, so that the air can be exhausted more efficiently. The hot air 3 exhausted from the exhaust fan 38 in the projection light 36 from the projection lens 37
The problem that the projected image on the screen fluctuates due to the flow of 9 is that the effect of the exhaust wind 39b far from the projection lens 37 side is smaller than that of the exhaust wind 39b close to the projection lens 37.
Thus, the direction of the wind direction plate 40 is larger than the inclination angle c of the wind direction plate 40a.
The inclination angle d of b is made smaller.

In this embodiment, the first outgoing light 13 separated by the first dichroic mirror 12 is the reflected light of the first dichroic mirror 12 and the second outgoing light separated by the first dichroic mirror 12. The first dichroic mirror 12 is transmitted through the first dichroic mirror 12 so that the first
The first reflecting mirror 10, the second lens array 11, the first dichroic mirror 12, the second dichroic mirror 19, and the third reflecting mirror 26 are arranged in this order, and the first reflecting mirror 10, the first lens An array 4, a metal halide lamp 1 as a light source, and an exhaust fan 38 are arranged in this order, and a first reflecting mirror 10, a first lens array 4, a metal halide lamp 1 as a light source, and an exhaust fan 38 are arranged in a projection lens. 37, the dichroic prism 35, and the second dichroic mirror 19 are arranged substantially parallel to and adjacent to the arrangement of the dichroic mirror 19.

According to the liquid crystal projector of this embodiment, the hot air 39 exhausted by the exhaust fan 38 flows in the same direction as the light 36 emitted from the projection lens 37.
It is impossible for the viewer to be positioned in the vicinity of the direction of the light 36 emitted from the projection lens 37 because the viewer himself blocks the emitted light 36 and generates a shadow on the image on the screen. Therefore, since it does not flow in the direction of the viewer located near the liquid crystal projector, the viewer does not feel uncomfortable.

For the same reason, even when an image device such as a personal computer is used in the vicinity of a liquid crystal projector, hot air does not hit these heat-sensitive devices, and there is no need to consider the position of the device. is there. Also,
In order to efficiently exhaust the heat generated from the light source, there is no need to take care not to place an object that blocks the exhaust at the position where the hot air is exhausted, so that usability can be improved.

In this embodiment, the first dichroic mirror 12 has a spectral characteristic of reflecting B-color light and transmitting G-color light and R-color light.
Has a spectral characteristic of reflecting the G color light and transmitting the R color light, so that the B color light component can be relatively increased as compared with the R color light component. This is because only the B-color light can be used only by reflection at each of the mirrors 10, 12, and 15, and the S-polarized light component having a higher reflectance than the P-polarized light component can be used. This has the effect of increasing the white color projected on the screen to a desirable color temperature. Especially,
Glass and plastic materials for optical components used in liquid crystal projectors include those that reduce the light use efficiency of B color light (for example, polarizing plates and liquid crystal panels). In the case of these materials, a light source with the same color temperature must be used. Even when used, a decrease in color temperature was inevitable. However, in such a configuration of the present invention,
Since the B-color light component can be used to the maximum, this decrease in color temperature can be minimized.

It should be noted that, compared to the B-color light and the G-color light, the R-color light requires extra use of the relay lenses 25 and 27 and the reflection mirrors 26 and 28. I do.

Therefore, in the present embodiment, the first reflecting mirror is the enhanced silver mirror 10, the third reflecting mirror is the cold mirror 26 that transmits infrared rays, and the fourth reflecting mirror is the enhanced silver mirror 28. I do.

FIG. 2 is a graph showing the spectral reflectance characteristics of the enhanced reflection silver mirror. FIG. 3 is a graph of the spectral transmittance of the cold mirror. From this figure, it can be seen that the reflective silver mirror has a higher reflectance than the cold mirror. In particular, since the R-color light uses the transmitted light of the dichroic mirrors 12, 19, the P-polarized light component having a higher transmittance than the S-polarized light component should be used. Therefore, the enhanced reflection silver mirror 1 having a higher reflectance of the P-polarized component
By adopting 0 and 28, the reduction of the R color light can be minimized. In addition, the reflection-enhancing silver mirror 10,
With the adoption of 28, it is necessary to block unnecessary infrared rays and ultraviolet rays. Therefore, in the present embodiment, the third reflecting mirror is a cold mirror 26 that transmits infrared rays. Thereby, harmful infrared rays can be prevented from being irradiated to the polarizing plate 30 and the liquid crystal panel 31.

In this embodiment, the first liquid crystal panel 1
A UV cut filter for blocking ultraviolet rays is arranged between the optical path of the polarizing plate 17 and the first dichroic mirror 12 arranged on the incident side of the light source 8. Further, in this embodiment,
A UV cut filter 17a is also formed on the incident surface of the polarizing plate 17.

In the first embodiment, the exhaust fan 3
8 so that the exhaust air 39 of FIG. 8 moves away from the projection light 36 of the projection lens 37, the exhaust fan 38 is arranged at an angle, a plurality of wind direction plates 40 are arranged at an angle, and the wind direction on the side close to the projection lens 37. The inclination angle c of the plate 40a is set to be larger than the inclination angle d of the wind direction plate 40b farther from the projection lens 37, but is not limited to this.

FIG. 4 is a diagram showing a second embodiment of the present invention, and is a top view of a liquid crystal projector optical system. The configuration is the same as that of the first embodiment of the present invention, except that the exhaust fan 38 is not arranged at an inclination and the configuration of the wind direction plate 40 is not shown. In the present embodiment, similarly to the second embodiment, the hot air 39 exhausted from the exhaust fan 38 is used.
However, it does not flow in the direction of the viewer located near the liquid crystal projector, does not cause discomfort to the viewer, does not require consideration for the equipment placed near the liquid crystal projector, and generates hot air. It is not necessary to take care not to place anything that blocks the exhaust at the position where the air is exhausted. As described above, according to the present invention, an easy-to-use liquid crystal projector can be obtained.

FIG. 5 is a view showing a third embodiment of the present invention, and is a top view of the optical system.

Light 51 from a metal halide lamp 50 as a light source is supplied to a parabolic mirror lamp reflector 52, a UV-IR.
A cut filter 53, a first lens array 54, a cold mirror 55 as a first reflection mirror, a second lens array 56, and a dichroic mirror 40 as a first dichroic mirror for R-color light reflection, G and B-color light transmission. Then, the R color light 58 is reflected, and the G and B color lights 59 are transmitted. The R-color light 58 is reflected by a reflection-enhancing aluminum mirror 60 that is a second reflection mirror, and a condenser lens 61,
The light is incident on a liquid crystal panel 63 for R color light, which is a first transmission type liquid crystal panel, via a polarizing plate 62. G and B light 59
Is a second dichroic mirror, G color light reflection, B
The light enters a dichroic mirror 64 that transmits color light, the G light 65 is reflected, and the B light 66 is transmitted. G color light 65
Through a condenser lens 67 and a polarizing plate 68, the light enters a liquid crystal panel for G color light 69 which is a second transmission type liquid crystal panel. The B-color light 66 is transmitted through a relay lens 70, an increased reflection aluminum mirror 71 serving as a third reflection mirror, and a relay lens 7.
2. Increasing reflection aluminum mirror 73 as a fourth reflection mirror,
The light is incident on a B-color light liquid crystal panel 76 as a third transmission type liquid crystal panel via a condenser lens 74 and a polarizing plate 75.

The R transmitted light 77 from the liquid crystal panel 63, the G transmitted light 78 from the liquid crystal panel 69, and the B transmitted light 79 from the liquid crystal panel 76 are color-combined by a dichroic prism 80, and the color-combined emission light 81 to projection lens 8
2 project onto a screen (not shown).

In order to prevent heat generated by the high-temperature light source from affecting components other than the light source, an exhaust fan 38 for cooling the light source is arranged near the metal halide lamp 50 and the lamp reflector 52 of the light source. Then, the hot air 39 is exhausted outside a housing (not shown) of the liquid crystal projector.

In this embodiment, the first outgoing light 58 separated by the first dichroic mirror 40 is the reflected light of the first dichroic mirror 40, and the second outgoing light separated by the first dichroic mirror 40. The first dichroic mirror 40 is transmitted through the first dichroic mirror 40 so that the first
, A second lens array 56, a first dichroic mirror 40, a second dichroic mirror 64, and a third reflecting mirror 71 are arranged in this order, and the first reflecting mirror 55 and the first lens The array 54, the metal halide lamp 50 of the light source, and the exhaust fan 38 are arranged in this order, and the arrangement of the first reflecting mirror 55, the first lens array 54, the metal halide lamp 50 of the light source, and the exhaust fan 38 is such that the projection lens 82, The dichroic prism 80 and the second dichroic mirror 64 are arranged substantially parallel to and adjacent to the arrangement of the dichroic mirror 64.

According to the present embodiment, the hot air 39 exhausted by the exhaust fan 38 flows in the same direction as the light 81 emitted from the projection lens 82, so that the same effect as in the second embodiment is obtained. Is obtained.

[0047]

As described above, according to the present invention, a liquid crystal display having good usability, such as giving no discomfort to the viewer and eliminating the need to consider the rise in temperature of devices disposed in the vicinity. You can get a projector,
Fluctuation of the projected image on the screen due to the hot air exhausted from the exhaust fan can also be prevented. Also, the cooling efficiency can be increased by increasing the exhaust efficiency.

[Brief description of the drawings]

FIG. 1 is a top view of a liquid crystal projector optical system according to a first embodiment of the present invention.

FIG. 2 is a graph showing a spectral reflectance characteristic of the enhanced reflection silver mirror.

FIG. 3 is a graph of a spectral transmittance of a cold mirror.

FIG. 4 is a top view of a liquid crystal projector optical system according to a second embodiment of the present invention.

FIG. 5 is a top view of a liquid crystal projector optical system according to a third embodiment of the present invention.

FIG. 6 is a top view of a conventional liquid crystal projector optical system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Metal halide lamp, 2 ... Illumination light, 3 ... Lamp reflector, 4 ... First lens array, 5 ... Lamp reflector, 6 ... Illumination light, 7 ... Incident surface, 8 ... Convergent light, 9 ... Emission light, 10 ... Enhanced reflection silver mirror, 11: second lens array, 12: dichroic mirror, 13: B color light, 14
... G and R color light, 15 ... High reflection aluminum mirror, 16 ...
Condenser lens, 17: polarizing plate, 17a: UV cut filter, 18: liquid crystal panel for B color light, 19: dichroic mirror, 20: G color light, 21: R color light, 22: condenser lens, 23: polarizing plate, 24: G Liquid crystal panel for colored light, 25: relay lens, 26: cold mirror, 2
7 relay lens, 28 enhanced silver mirror, 29 condenser lens, 30 polarizing plate, 31 liquid crystal panel for R color light, 32 B transmitted light, 33 G transmitted light, 34 R transmitted light, 35 Dichroic prism, 36 ... outgoing light, 3
6a: outgoing light, 37: projection lens, 38: exhaust fan,
39 hot air, 39a hot air, 39b hot air, 40 wind plate, 40a wind plate, 40b wind plate, a angle, b
Angle, c: angle, d: angle, 50: metal halide lamp, 51: illumination light, 52: lamp reflector, 53: U
V-IR cut filter, 54 first lens array,
55: cold mirror, 56: second lens array, 5
7: dichroic mirror, 58: R color light, 59: G and B color light, 60: enhanced reflection aluminum mirror, 61: condenser lens, 62: polarizing plate, 63: liquid crystal panel for R color light, 64: dichroic mirror, 65: G Color light, 66
... B color light, 67 ... condenser lens, 68 ... polarizer, 6
9 ... G-color liquid crystal panel, 70 ... Relay lens, 71 ...
Increasing reflection aluminum mirror, 72: relay lens, 73: increasing reflection aluminum mirror, 74: condenser lens, 75: polarizing plate, 76: liquid crystal panel for B color light, 77: R transmitted light, 78
.. G transmission light, 79 B transmission light, 80 dichroic prism, 81 outgoing light, 82 projection lens, 83 exhaust fan, 84 hot air.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hisao Inage 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Visual Information Media Division of Hitachi, Ltd. (72) Takashi Tsunoda 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Hitachi, Ltd. Multimedia System Development Division

Claims (11)

[Claims] A liquid crystal projector for irradiating a liquid crystal panel with light from a light source and projecting outgoing light from the liquid crystal panel onto a screen with a projection lens, comprising: an exhaust fan for exhausting air inside the device to the outside; A liquid crystal projector having an exhaust fan disposed close to the projection lens and inclined with respect to the direction of the optical axis of the projection lens so that the exhaust flow is away from the projection light of the projection lens. 2. A liquid crystal projector for irradiating a liquid crystal panel with light from a light source and projecting light emitted from the liquid crystal panel onto a screen with a projection lens, comprising: an exhaust fan for exhausting air inside the device to the outside; An exhaust fan arranged close to the projection lens, and a wind direction plate inclined with respect to the optical axis direction of the projection lens so that the exhaust flow of the exhaust fan moves away from the projection light of the projection lens. A liquid crystal projector characterized by the following. 3. A liquid crystal projector that irradiates light from a light source to a liquid crystal panel and projects light emitted from the liquid crystal panel onto a screen by a projection lens. The fan exhaust flow is arranged at an angle to the optical axis direction of the projection lens so as to move away from the projection light of the projection lens, and the inclination angle of the object closer to the projection lens and the inclination angle of the object farther from the projection lens are different. A liquid crystal projector comprising: a plurality of wind direction plates which are different from each other. 4. A liquid crystal projector that irradiates light from a light source onto a liquid crystal panel and projects light emitted from the liquid crystal panel onto a screen by a projection lens, comprising: an exhaust fan that exhausts air inside the device to the outside; The fan exhaust air flow is inclined with respect to the direction of the projection lens optical axis so as to be away from the projection light of the projection lens, and the angle of inclination of the object closer to the projection lens is greater than the angle of inclination of the object farther from the projection lens. A liquid crystal projector, comprising: a plurality of wind direction plates whose sizes are also increased. 5. A liquid crystal projector that irradiates light from a light source onto a liquid crystal panel and projects light emitted from the liquid crystal panel onto a screen with a projection lens, wherein the exhaust fan exhausts air inside the device to the outside. An exhaust fan that is arranged close to the projection lens and that is inclined with respect to the direction of the optical axis of the projection lens so that the exhaust air flows away from the projection light of the projection lens; and that the exhaust air flow from the exhaust fan moves away from the projection light of the projection lens. A liquid crystal projector, comprising: a wind direction plate inclined with respect to an optical axis direction of a projection lens. 6. A liquid crystal projector for irradiating a liquid crystal panel with light from a light source and projecting light emitted from the liquid crystal panel onto a screen with a projection lens, comprising: an exhaust fan for exhausting air inside the device to the outside; An exhaust fan that is arranged close to the projection lens and that is inclined with respect to the optical axis of the projection lens so that the exhaust flow is away from the projection light of the projection lens; and the exhaust flow of the exhaust fan is away from the projection light of the projection lens. A plurality of wind direction plates arranged so as to be inclined with respect to the direction of the optical axis of the projection lens, and having a different inclination angle between the one closer to the projection lens and the one farther from the projection lens. A liquid crystal projector comprising: 7. A liquid crystal projector for irradiating light from a light source to a liquid crystal panel and projecting light emitted from the liquid crystal panel onto a screen by a projection lens, comprising: an exhaust fan for exhausting air inside the device to the outside; An exhaust fan disposed close to the projection lens and inclined with respect to the direction of the optical axis of the projection lens so that the exhaust air flows away from the projection light of the projection lens; Are arranged at an angle with respect to the direction of the optical axis of the projection lens so as to be away from the projection light of the projection lens, and the inclination angle of the object closer to the projection lens is larger than the inclination angle of the object farther from the projection lens. A liquid crystal projector comprising: a wind direction plate; 8. A light from a light source is made incident on a first dichroic mirror via a first lens array, a first reflection mirror, and a second lens array, and color-separated by the first dichroic mirror. Irradiating the first liquid crystal panel with the first emitted light via a second reflecting mirror, and causing the second emitted light, which has been color-separated by the first dichroic mirror, to be incident on a second dichroic mirror, The first output light color-separated by the second dichroic mirror is
Irradiates the third liquid crystal panel through a third reflecting mirror and a fourth reflecting mirror, and irradiates the second liquid crystal panel with the second emitted light color-separated by the second dichroic mirror. The transmitted light from the liquid crystal panel, the transmitted light from the second liquid crystal panel, and the transmitted light from the third liquid crystal panel are color-combined by a dichroic prism, and the color-combined outgoing light is screened by a projection lens. A liquid crystal projector for projecting above, comprising: a first reflecting mirror, a second lens array, a first dichroic mirror, a second dichroic mirror, and a third reflecting mirror arranged in this order; The reflection mirror, the first lens array, the light source, and the exhaust fan are arranged in this order, and the arrangement of the first reflection mirror, the first lens array, the light source, and the exhaust fan is a projection lens. , Dichroic prism,
A liquid crystal projector characterized by being arranged substantially parallel to and adjacent to the arrangement of the second dichroic mirror. 9. The first dichroic mirror has a spectral characteristic of reflecting B light and transmitting G light and R light, and the second dichroic mirror reflects G light.
9. The liquid crystal projector according to claim 8, having a spectral characteristic transmitting R-color light. 10. A cold mirror, wherein one of the third reflecting mirror and the fourth reflecting mirror is an enhanced reflecting silver mirror, and the other is an infrared-transmitting infrared mirror. The liquid crystal projector according to claim 8, wherein 11. The first reflection mirror is an enhanced reflection silver mirror, and a UV for blocking ultraviolet light is provided between an optical path between a polarizing plate disposed on the incident side of the first liquid crystal panel and the first dichroic mirror. 9. The liquid crystal projector according to claim 8, further comprising a cut filter.