JPH10161241A - Projection type display device and infrared ray reflection element therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the service life deterioration of a light source lamp due to infrared ray. SOLUTION: A lens array 200 is arranged on an optical path of emission light outgoing from a light source part 100 so that the lens surface with a curved surface shape of the lens array 200 becomes an incident surface of light. A filter FIR interrupting at least the infrared ray is formed on the lens surface with the curved surface shape of the lens array 200. Since the infrared ray IR outgoing from the light source part 100 is reflected radially by the filter FIR, the infrared ray IRR again made incident on the light source lamp 101 is reduced to a certain extent, and the occurrence of the damage, deformation and cloud, etc., in the lamp due to the temp. rising of the light source lamp 101 is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection display device for displaying an image on a projection surface using light emitted from a light source, and an infrared reflection element used for the same.

[0002]

2. Description of the Related Art As a light source of a projection display device, a light source lamp for outputting a radial white light beam is used. FIG.
1 is a schematic configuration diagram showing a conventional light source unit in a projection display device. The light source unit 50 includes a light source lamp 51 and a concave mirror 52 that emits radiation emitted from the light source lamp 51 as a substantially parallel light beam. The light source unit 5
The lens array 70 is arranged on the optical path of the parallel light flux emitted from the zero. The lens array 70 includes the light source unit 5
The parallel light beam emitted from 0 is split into a plurality of split light beams by the light beam splitting lens 71 constituting the lens array 70. Usually, between the light source unit 50 and the lens array 70,
A flat plate (filter plate) 60 having a filter that reflects infrared rays (IR cut filter) and a filter that reflects ultraviolet rays (UV cut filter) is provided. here,
Infrared rays cause a temperature rise in a portion irradiated with the infrared rays, thereby causing a device defect, particularly a defect of a liquid crystal panel and a polarizing plate which are light modulation means of a projection display device. Ultraviolet rays also cause a chemical change or the like in an irradiated portion, and cause a device failure, particularly a defect in a liquid crystal panel, a polarizing plate, and the like, similarly to infrared rays. Therefore, by providing the filter plate 60, the light source unit 50 is provided.
Infrared and ultraviolet light contained in the white light emitted from the lens array 70 are blocked, and the components of the projection display device disposed after the lens array 70 are caused by device failure or chemical change due to heat generated due to the infrared or ultraviolet light. This prevents equipment failure.

[0003]

Generally, the filter provided on the filter plate 60 is of a reflection type. Here, the filter plate 60 emitted from the light source unit 50
Is almost reflected by the filter plate 60 and irradiates the light source unit 50 again. This infrared reflected light IR
R irradiates the light source lamp 51 by following the optical path in reverse.
Accordingly, the temperature of the light source lamp 51 increases due to the irradiated infrared IRR. This increase in temperature causes deformation or breakage of the glass of the lamp, opacity, and the like, and causes deterioration of the life of the light source lamp.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the prior art, and has as its object to provide a technique for reducing the life degradation of a light source lamp due to infrared rays in a projection display device. .

[0005]

In order to solve at least a part of the above-mentioned problems, a first aspect of the present invention is a projection display device, comprising a light source and light emitted from the light source. And a modulating means for modulating the intensity of light. An infrared reflecting element having an infrared reflecting film formed on a curved surface of a lens is provided between the light source and the modulating means.

According to the first aspect, the infrared rays are radially reflected by the infrared reflecting film formed on the curved surface, so that the infrared rays reflected by the infrared reflecting film and irradiating the light source again can be reduced. Therefore, in the projection display device,
The life degradation of the light source due to infrared rays can be reduced.

In the first invention, it is preferable that an ultraviolet shielding film is further formed on the infrared reflecting element.

[0008] If a separate ultraviolet light blocking means is provided, light loss due to light reflection at the interface will increase. According to the above configuration, the loss of light can be reduced as compared with the case where the ultraviolet ray blocking means is separately provided.

Further, in the first invention, it is preferable that the infrared reflecting element has a curved surface of a lens disposed on a light source side.

With this arrangement, the light passing through the lens is refracted twice when entering the lens and when exiting the lens. Therefore, when assuming the same focal length as when the curved surface of the lens is not disposed on the light source side, a lens having a smaller curvature can be used, thereby reducing image distortion and the like due to lens aberration. Thus, the light use efficiency can be improved. In addition, when lenses having the same curvature are used, the distance between the light source and the modulation element can be reduced, and the device can be downsized.

According to a second aspect of the present invention, there is provided a light source and a first optical element having a plurality of lenses arranged in a matrix, condensing light emitted from the light source and converting the light into a plurality of intermediate light beams separated from each other. A second optical element having a plurality of lenses respectively corresponding to the plurality of lenses of the first optical element, and a modulation for modulating light emitted from the second optical element based on given image information Means, the curved surfaces of the plurality of lenses of the first optical element, or the second
An infrared reflective film is formed on a curved surface of the plurality of lenses of the optical element.

According to the second invention, infrared rays are radially reflected by the infrared reflecting film formed on the curved surfaces of the plurality of lenses of the first optical element or the curved surfaces of the plurality of lenses of the second optical element. Therefore, similarly to the first invention, it is possible to reduce the amount of infrared light reflected by the infrared reflecting film and irradiating the light source again. Therefore, in the projection display device, it is possible to reduce the life degradation of the light source due to infrared rays.

[0013] In the second invention, it is preferable that an ultraviolet shielding film is formed on the first optical element or the second optical element.

According to the above configuration, as in the first aspect,
Light loss can be reduced as compared with the case where an ultraviolet ray blocking means is separately provided.

Further, in the second invention, it is preferable that at least one of the first optical element and the second optical element has a curved surface disposed on a light source side.

With this arrangement, the aberration of the lens can be reduced, as in the first aspect, or
It is possible to reduce the distance between the first optical element, the second optical element, and the modulating means.

According to a third aspect of the present invention, there is provided a light source and a first optical element which has a plurality of lenses arranged in a matrix, condenses light emitted from the light source, and converts the light into a plurality of intermediate light beams separated from each other. A second optical element having a plurality of lenses respectively corresponding to the plurality of lenses of the first optical element, the first optical element, and the plurality of intermediate light beams passing through the second optical element And a modulating means for modulating the light emitted from the superimposing lens based on given image information, wherein the plurality of lenses of the first optical element, the second An infrared reflective film is formed on a curved surface of one of the plurality of lenses of the optical element and the superimposed lens.

According to the third aspect, the infrared reflecting film formed on the curved surface of any one of the plurality of lenses of the first optical element, the plurality of lenses of the second optical element, or the superposed lens. Because the infrared rays are reflected radially,
Similarly to the second aspect, it is possible to reduce infrared rays reflected on the curved surface of the lens and irradiating the light source again. Therefore, in the projection display device, it is possible to reduce the life degradation of the light source due to infrared rays.

In the third aspect, it is preferable that an ultraviolet light blocking film is formed on any one of the first optical element, the second optical element, and the superimposing lens.

According to the above configuration, similarly to the first and second aspects, the loss of light can be reduced as compared with the case where the ultraviolet ray blocking means is separately provided.

In the third invention, a curved surface of at least one of the plurality of lenses of the first optical element, the plurality of lenses of the second optical element, and the superimposed lens is on the light source side. It is also preferred that they are arranged.

With such an arrangement, the aberration of the lens can be reduced as in the first and second aspects of the present invention, or the first and second optical elements or the superimposing lens and the modulating means can be used. Can be reduced.

A fourth invention is an infrared reflecting element,
It is characterized by comprising a lens having a curved surface on which an infrared reflecting film for reflecting infrared light is formed.

According to the fourth aspect, similarly to the first to third aspects, it is possible to reduce the amount of the infrared light that is reflected by the infrared reflecting film and returns to the light incident direction. Therefore, the amount of infrared rays returning to the light source can be reduced, and the life degradation of the light source can be reduced.

In a fourth aspect, a plurality of the curved surfaces may be provided in a matrix.

In this way, it can be used as an optical element for splitting light from a light source.

Further, an ultraviolet blocking film may be formed.

This makes it possible to realize an optical element capable of blocking both ultraviolet light and infrared light with a simple structure.

[0029]

Next, embodiments of the present invention will be described based on examples. FIG. 1 is a schematic plan view of a projection display according to a first embodiment of the present invention. This projection display device includes a polarized light illumination device 10, dichroic mirrors 801 and 804, and reflection mirrors 802, 807 and 809.
, Relay lenses 806, 808, 810, and three liquid crystal panels (liquid crystal light valves) 803, 805, 811
, A cross dichroic prism 813, and a projection lens 814.

The polarization illuminating device 10 includes a light source unit 100 for emitting a substantially parallel light beam, a first lens array 200,
A second lens array 300, a polarization conversion element 310 for converting incident light into a predetermined linearly polarized light component, and a condenser lens 39
0. The polarized light device 10 includes a light source unit 100
A light beam having a random polarization direction including a s-polarized light (light in an in-plane vibration direction) component and a p-polarized light (light in a direction perpendicular to the s-polarized light) component emitted from The light is converted into linearly polarized light, and the three liquid crystal light valves 803, 805, and 811 as the illuminated area are illuminated almost uniformly.

The light source unit 100 includes a light source lamp 101 and a parabolic reflector 102. Light source lamp 1
The light radiated from 01 is reflected in one direction by the parabolic reflector 102 and emitted as a substantially parallel light flux.

FIG. 2 is a perspective view showing the appearance of the first lens array 200. As shown in FIG. 2, the lens array 200 is a minute light beam splitting lens 2 having a rectangular contour.
01 are arranged vertically and horizontally. The lens array 200 has a light source optical axis R (FIG. 1)
It is arranged so as to coincide with the center of 00. The external shape of each light beam splitting lens 201 as viewed from the Z direction is set so as to be substantially similar to the shape of the liquid crystal light valves 803, 805, 811 which are the illuminated areas. However,
They do not have to be similar.

The second lens array 300 has substantially the same configuration as the first lens array 200 shown in FIG. That is, the second lens array 300 is configured by arranging a plurality of condensing lenses 301 in the same number as the number of light beam splitting lenses 201 included in the first lens array 200 in a matrix. The center of the second lens array 300 is also arranged so as to coincide with the light source optical axis R.

FIG. 3 is an explanatory diagram showing the configuration of the polarization conversion element 310 (FIG. 1). The polarization conversion element 310 includes a polarization beam splitter array 320 and a selective retardation plate 38.
0. Polarizing beam splitter array 320
Has a shape in which a plurality of columnar translucent plate members 322 each having a parallelogram cross section are alternately bonded.
Polarized light separating films 331 and reflective films 332 are formed alternately on the interface of the light transmitting plate 322. The polarizing beam splitter array 320 is formed by laminating a plurality of glass plates having these films so that the polarization separating films 331 and the reflecting films 332 are alternately arranged, and cuts obliquely at a predetermined angle. Created by doing. In addition, such a translucent plate material, for example, a plate glass is called a “substrate”,
In addition, a block in which a plurality of translucent plate members are bonded or a block cut out therefrom may be referred to as a “substrate block”.

First and second lens array lays 200, 3
00 passes through the polarization conversion element 3 shown in FIG.
10 is incident. The incident light having a random polarization direction including the s-polarized light component and the p-polarized light component is first separated by the polarization splitting film 331 into s-polarized light and p-polarized light. The s-polarized light is reflected by the polarization separation film 331 at a substantially right angle, and further reflected by the reflection film 332 at a right angle, and then emitted. On the other hand, the p-polarized light is
Is transmitted as it is. The selective retardation plate 380 has a λ / 2 retardation plate 3 on the exit surface of the light transmitted through the polarization separation film 331.
An optical element 81 is formed, and the light-emitting surface portion of the light reflected by the reflection film 332 is colorless and transparent. Therefore, the p-polarized light transmitted through the polarization separation film 331 is λ / 2
The light is converted into s-polarized light by the phase difference plate 381 and emitted. Therefore, only the s-polarized light is selectively emitted from the polarization conversion element.

The light source unit 100 emits a substantially parallel white light beam having a random polarization direction. Light beams emitted from the light source unit 100 and incident on the first lens array 200 are split into a plurality of split light beams by the respective light beam splitting lenses 201. Each split light beam is divided into a light beam splitting lens 2
01 and the light condensing lens 301 converge in a plane perpendicular to the system optical axis L. At the positions where the divided light beams converge, the same number of light source images as the number of light beam splitting lenses 201 are formed. The position where the light source image is formed is almost at the center of the polarization splitting film 331 in the polarization beam splitter array 320.

The light beam incident on the polarizing beam splitter array 320 is, as shown in FIG.
All are converted to s-polarized light. The light beam emitted from the polarizing beam splitter array 320 is illuminated by the condenser lens 390, that is, the liquid crystal light valve 803,
Illuminate 805, 811. The condensing lens 390 superimposes a number of partial light beams split by the number of light beam splitting lenses 201 to form the liquid crystal light valve 80 which is an illuminated area.
It has a function as a superimposing optical system for condensing light at 3,805,811. Therefore, each of the liquid crystal light valves 803, 80
5,811 is evenly illuminated throughout.

Two dichroic mirrors 801 and 80
Reference numeral 4 denotes a white light beam emitted from the polarized light illumination device 10 as red,
It has a function as a color light separating unit that separates the light into three color lights of blue and green. Three liquid crystal light valves 803, 805,
811 according to the given image information (image signal)
It has a function as light modulating means for modulating and emitting the three color lights. Cross dichroic prism 81
Reference numeral 3 has a function as a color light combining unit that combines the three color lights and projects the light in the direction of the projection lens 814. The projection lens 814 has a function as a projection optical system that projects light representing a synthesized color image on a screen 815.

A blue light green light reflecting dichroic mirror 801
Transmits the red light component of the white light flux emitted from the polarized light illumination device 10 and reflects the blue light component and the green light component. The transmitted red light is reflected by the reflection mirror 802 and reaches the red light liquid crystal light valve 803. On the other hand, of the blue light and the green light reflected by the first dichroic mirror 801, the green light is reflected by the green light reflecting dichroic mirror 804 and reaches the green light liquid crystal light valve 805. On the other hand, the blue light also passes through the second dichroic mirror 804.

In this embodiment, the optical path length of the blue light is the longest of the three color lights. Therefore, for blue light, after the dichroic mirror 804, the incident lens 8
, A light guide unit 850 configured by a relay lens system including a relay lens 808, and an emission lens 810. That is, after transmitting the blue light through the green light reflecting dichroic mirror 804, first, the incident lens 8
06 and the reflection mirror 807, the relay lens 808
It is led to. Further, the light is reflected by the reflection mirror 809 and guided to the emission lens 810, and reaches the liquid crystal light valve for blue light 811.

The three liquid crystal light valves 803, 805,
811 modulates each color light in accordance with an image signal (image information) provided from an external control circuit (not shown), and generates color light including image information of each color component. The modulated three color lights enter the cross dichroic prism 813. In the cross dichroic prism 813, a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in a cross shape. Three color lights are synthesized by these dielectric multilayer films,
Light representing a color image is formed. The synthesized light is projected onto a screen 8 by a projection lens 814 which is a projection optical system.
15, and the image is enlarged and displayed.

FIG. 4 is an explanatory diagram showing only a main part of the projection type display device according to the first embodiment for explaining the features of the projection type display device. The first embodiment has a feature in the first lens array 200. The first lens array 200 has a curved light incident surface, an infrared filter (IR cut filter) FIR formed on the curved surface, and an ultraviolet filter (UV cut filter) FUV on a flat exit surface. Is formed. Such a first lens array 200 is shown in FIG.
When used in the projection display device shown in FIG. 1, the ultraviolet light emitted from the light source unit 100 is reflected by the UV cut filter FUV, and is not irradiated to the optical system after the first lens array 200. Further, the infrared ray IR emitted from the light source unit 100 is reflected by an IR cut filter FIR formed on the incident surface of the first lens array 200, and is similarly applied to the optical system after the first lens array 200. Never. Therefore, it is possible to prevent the optical system after the first lens array 200 from deteriorating due to infrared rays or ultraviolet rays.

On the other hand, the infrared rays IR reflected by the IR cut filter FIR are radially reflected because the IR cut filter FIR is formed on the curved surface of the first lens array as shown in FIG. Accordingly, the infrared rays IRR reflected by the IR cut filter FIR and re-entering the light source lamp 101 are reduced to some extent, and the occurrence of lamp damage, deformation, cloudiness, and the like due to the temperature rise of the light source lamp 101 can be reduced.

When the curved surface of the first lens array 200 is arranged to face the liquid crystal light valve and the plane thereof is directed to the light source unit 100, the parallel light incident on the first lens array 200 will be reflected on the curved surface of the lens. Light is condensed only by the refraction of light. On the other hand, as shown in FIG. 4, when the curved surface of the first lens array 200 is directed toward the light source unit 100, the parallel light incident on the first lens array 200 is emitted from the lens when it is incident on the lens. Time is refracted twice. Therefore, when using lenses with the same curvature,
As shown in FIG. 4, the first lens array 2
Since the focal length can be shortened by arranging the curved surface No. 00 toward the light source unit 100, the distance between the first lens array 200 and the polarizing beam splitter 310 (FIG. 1) can be shortened. This is more advantageous in that the size of the device can be reduced.

When the distance between the first lens array 200 and the polarizing beam splitter 310 (FIG. 1) is not changed, as shown in FIG.
When the curved surface of “0” is arranged toward the light source unit 100 side, a lens having a smaller curvature can be used as compared with the case where the flat surface is arranged toward the light source unit 100 side, thereby reducing the occurrence of image distortion and the like due to aberration. However, it is more advantageous in that the light use efficiency can be improved.

FIG. 5 is an explanatory diagram showing a main part of the second embodiment. The second embodiment shows an example in which an IR cut filter FIR and a UV cut filter FUV are formed in multiple layers on the curved incident surface of the first lens array 200.
The order of forming the multilayer is arbitrary, but the light source unit 1 using infrared rays
Taking into account the degree of adverse effect on the lower layer, the upper layer is an IR cut filter FIR and the lower layer is a UV cut filter FIR.
UV is more preferable. Since the operation of the second embodiment is almost the same as that of the first embodiment, the description is omitted. If both the IR cut filter FIR and the UV cut filter FUV are formed in such a manner as described above,
Since the filter can be formed in the same process, the process cost can be reduced. On the other hand, as shown in FIG. 4, when the IR cut filter FIR and the UV cut filter FUV are formed on different surfaces, the number of dielectric multilayer films formed on one surface can be small, so Peeling and deterioration of the film hardly occur, and there is an effect that the reliability of the filter is improved.

The present invention is not limited to the above examples and embodiments, but can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

(1) The gist of the present invention is to prevent the life of a light source lamp from being deteriorated due to a rise in temperature, such as breakage or deformation.
The purpose is to reduce the amount of reflection of infrared light emitted from a light source lamp by reflecting or reflecting irregularly the reflected light of an infrared ray in an IR cut filter. Therefore, the liquid crystal light valve 80
The IR cut filter FIR may be formed on a curved surface of a lens which is disposed on the optical path up to 3,805,811 and has a curved surface. For example, the second
May be configured similarly to the first or second embodiment. Further, the surface of the condenser lens 390 on the light source unit 100 side may be formed into a curved shape, and an IR cut filter may be provided on this surface. Furthermore, another condensing lens may be provided, and an IR cut filter may be provided on this curved surface.

According to the above, as in the first and second embodiments, since the infrared rays are radially reflected by the IR cut filter FIR, the reflection of the infrared rays to the light source unit 100 can be reduced. However, in the above-described first and second embodiments, the heat generated by the reflected light of the infrared ray is generated in a portion close to the light source lamp 101.
It is preferable that the first lens array 200 be provided on the curved surface closest to the light source unit 100 as in the second embodiment.

(2) Various films may be formed on the surface of the optical element of the present invention, in addition to the film that blocks infrared rays and ultraviolet rays. For example, an antireflection film for visible light may be formed.

(3) The optical element according to the present invention can be applied not only to the projection display apparatus shown in FIG. 1, but also to various other apparatuses. For example, instead of a color image,
The polarizing beam splitter array according to the present invention can be applied to a projection display device that projects a black-and-white image. In this case, in the apparatus shown in FIG. 1, only one liquid crystal panel is required, and a color light separating means for separating a light beam into three colors is provided.
A color light synthesizing means for synthesizing a color light beam can be omitted.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a projection display device according to a first embodiment.

FIG. 2 is a perspective view showing the appearance of a first lens array 200.

FIG. 3 is an explanatory diagram illustrating a configuration of a polarization conversion element 310.

FIG. 4 is an explanatory diagram showing a main part of the first embodiment.

FIG. 5 is an explanatory view showing a main part of a second embodiment.

FIG. 6 is a schematic configuration diagram showing a conventional light source unit in a projection display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Polarized illumination device 50 ... Light source part 51 ... Light source lamp 52 ... Concave mirror 60 ... Filter plate 70 ... Lens array 71 ... Light beam splitting lens 100 ... Light source part 101 ... Light source lamp 102 ... Parabolic reflector 200 ... First lens array 201: light beam splitting lens 300: second lens array 301: condenser lens 310: polarization conversion element 320: polarization beam splitter array 322: translucent plate material 331: polarization separation film 332: reflection film 380: selective phase difference plate 381 ... Λ / 2 retardation plate 390... Outgoing lens 801... Blue light and green light reflecting dichroic mirrors 802, 807, 809... Reflecting mirrors 803, 805 and 811. 808: relay lens 809: reflection mirrorー 810 ・ ・ ・ Emission lens 813 ・ ・ ・ Cross dichroic prism 814 ・ ・ ・ Projection lens 815 ・ ・ ・ Screen 850 ・ ・ ・ Light guide means

Claims (12)

[Claims] 1. An infrared reflecting element comprising: a light source; and a modulating means for modulating light emitted from the light source, wherein an infrared reflecting film is formed on a curved surface of a lens between the light source and the modulating means. A projection display device comprising: 2. The projection type display device according to claim 1, wherein an ultraviolet shielding film is further formed on the infrared reflecting element. 3. The projection display according to claim 1, wherein the infrared reflecting element has a curved surface of a lens disposed on a light source side. 4. A light source, a first optical element having a plurality of lenses arranged in a matrix, condensing light emitted from the light source, and converting the light into a plurality of intermediate light beams separated from each other; A second optical element having a plurality of lenses respectively corresponding to the plurality of lenses of the optical element; and a modulating means for modulating light emitted from the second optical element based on given image information. A projection display device, wherein an infrared reflecting film is formed on a curved surface of the plurality of lenses of the first optical element or a curved surface of the plurality of lenses of the second optical element. 5. The method according to claim 4, wherein the first optical element or the second optical element
A projection display device comprising an ultraviolet blocking film. 6. The projection display device according to claim 4, wherein a curved surface of at least one of the first optical element and the second optical element is disposed on a light source side. 7. A light source, a plurality of lenses arranged in a matrix, a first optical element for condensing light emitted from the light source, and converting the light into a plurality of intermediate light beams separated from each other; A second optical element having a plurality of lenses respectively corresponding to the plurality of lenses of the optical element, the first optical element, and the plurality of intermediate light beams having passed through the second optical element. A superimposing lens that emits light, and a modulating unit that modulates the light emitted from the superimposing lens based on given image information, wherein the plurality of lenses of the first optical element and the modulating means of the second optical element A projection display device, wherein an infrared reflecting film is formed on a curved surface of one of the plurality of lenses and the superimposed lens. 8. The projection display device according to claim 7, wherein an ultraviolet light blocking film is formed on any one of the first optical element, the second optical element, and the superimposing lens. 9. The curved surface of at least one of the plurality of lenses of the first optical element, the plurality of lenses of the second optical element, and the superimposing lens according to claim 7, wherein: A projection display device characterized in that: 10. An infrared reflecting element comprising a lens having a curved surface on which an infrared reflecting film for reflecting infrared light is formed. 11. The infrared reflecting element according to claim 10, wherein a plurality of the curved surfaces are provided in a matrix. 12. The infrared reflecting element according to claim 10, further comprising an ultraviolet blocking film.