JP2001043701A - Lighting optical device and projection device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To compactly constitute a multiple lighting type lighting optical system, to increase efficiency for light utilization and to make illuminance distribution of an irradiated part satisfactory. SOLUTION: Lamps with reflectors 121a to 121d are arrayed into an array shape, light from the lamp 121a is irradiated on the part of an irradiated part 123 via a lens 122 and light from the lamps 121b to 121d is irradiated on an other part of the irradiated part 123 via the lens 122 in the same way. An illuminance distribution from each lamp 121a to 121d is overlapped, although a peak position is different in the irradiated part 123. By the sum of overlapped optical strength distribution, pseudo-uniform illuminance can be contrived. The lens 22 may be constituted by a plurality of lens arrays, and the lens 22 can be eliminated by arranging optical axes of the lamp arrays with reflector toward the irradiated part 123.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an illumination optical system having a good illumination distribution at an illuminated portion and a compact optical system in a multi-lighting illumination optical system, and a projection apparatus using the same. It is.

[0002]

2. Description of the Related Art Hitherto, in an optical system using a plurality of lamps, a liquid crystal projection device for enlarging and projecting an image of a liquid crystal panel and a projection display device using a liquid crystal panel have been known. For example, JP-A-11-119149
In the liquid crystal projection device described in the publication, an optical system is configured by aligning and fixing a plurality of arc tubes to a radiation surface or an elliptical concave mirror. The light emitting section is fixed near the first focal position of the concave mirror. The reflected light is first illuminated by two first prisms consisting of triangular prisms,
The light exiting the first prism passes through a first fly-eye lens having a second prism on one surface and a plurality of lens groups on the other surface. Then, the light is reflected by the glass plate of the right-angle prism and is irradiated on the second fly-eye lens.
The second fly-eye lens has twice the number of lenses as the first fly-eye lens, and a plurality of phase difference plates for converting a P-wave into an S-wave are attached alternately to each lens. ing. After that, the light is separated into red, blue, and green by a plurality of mirrors, incident on three liquid crystal panels, synthesized by an X prism, and then incident on a projection lens. Further, for example, in a projection display device described in Japanese Patent Application Laid-Open No. 8-36180, a light transmission optical system guides a light beam emitted from a condensing optical system including a metal halide lamp and a parabolic mirror to a liquid crystal panel, and a liquid crystal. The projection lens enlarges and projects the optical image on the panel onto the screen to display a large-screen image. The light transmission optical system includes a first lens and a second lens, a beam combining lens, and a third lens.

[0003]

By the way, in the above-mentioned conventional liquid crystal projection device, a miniaturization of a multi-lit lamp projector is proposed by using a plurality of lamps and a fly-eye integrator. However, in the above-mentioned conventional example, there is a problem that the projector optical system mainly aims at miniaturization of the multi-lighting type lamp, and in particular, the entire projector optical system cannot be said to be small. That is, the volume increase of the light source unit due to multiple lighting is substantially equal to the volume increase of the projector optical system. Further, in the above-mentioned conventional projection display device, it has been proposed to realize a compact and inexpensive projection display device of a multi-lit lamp by using a plurality of lamps and a light transmission optical system. However, in the above-mentioned conventional example, there is a problem that only the multi-lighting type lamp is mainly made compact, and it cannot be said that the projection display device as a whole is particularly compact. Also in this case, the volume increase of the light source unit due to the multiple lighting is substantially equal to the volume increase of the light transmission optical system.

Accordingly, an object of the present invention is to solve these conventional problems, eliminate the space for the fly-eye integrator, and use a compact illumination optical system with a short optical length despite the use of a multi-lighting lamp. It is to provide a projection device using the same.

[0005]

In order to achieve the above object, the illumination optical system according to the present invention is characterized by comprising two or more light sources and at least one lens. It is also characterized by comprising two or more light sources and at least one lens array. In the above, it is also characterized in that the light sources are arranged in an array, and the same number of reflectors as the number of light sources are arranged in an array. In the above, it is also characterized in that the reflector array has a parabolic shape. In the above, the feature is that an arc lamp is used as a light source. It is also characterized in that two or more reflector-equipped arc lamps are arranged in an array, and the axial direction of each reflector-equipped lamp is arranged in a direction converging toward the irradiation part. Two or more light sources with reflectors are arranged in an array,
Each of the reflectors is in the shape of a spheroid, and the light source is arranged near the first focal point of the corresponding reflector, and each array of the lens array is arranged at each second focal point. In the projection display apparatus of the present invention, in the projection display apparatus including the light source, the illumination optical system, the image forming unit, and the projection optical system, the light source and the illumination optical system may be any one of the illumination optical systems according to any of the above. It is characterized by using.

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings. As described above, the conventional multi-lighting lamp projector has a configuration using a plurality of lamps and a fly-eye integrator. In particular, a large space is generated in the fly-eye integrator portion, and thus the projector cannot be downsized. The fly-eye integrator is a combination of a fly-eye lens and uniformly irradiates a portion to be irradiated such as a liquid crystal element. In the present invention, the space of the fly-eye integrator is reduced to achieve miniaturization. The direction of reduction is in the direction of the optical axis in the space of the fly-eye integrator. By using the illumination distribution characteristics of the light source and using a lamp with a reflector, the role of the fly-eye lens can be shared by the light source, or The space is reduced by using only the fly-eye lens and also having the function of the first fly-eye lens.

(First Embodiment) FIG. 8 is a sectional structural view (corresponding to claim 1) of an illumination optical system showing a first embodiment of the present invention. FIG. 9 is a characteristic curve diagram showing the illuminance distribution of the light source. As shown in FIG. 8, in the present embodiment, an illumination optical system is configured by two or more light sources 91 to 93 and at least one lens 94. Reference numeral 95 denotes a portion to be irradiated such as a liquid crystal element. Each of the light sources 91 to 93 irradiates a part of the illuminated portion 95 such as a liquid crystal element.
９３93 illuminate the entire irradiated portion 95. Light source 91
Since the light emitted from the light sources 93 to 93 irradiates the irradiated portion 95 such as a liquid crystal element via the lens 94, the effect of the present invention becomes more remarkable as the number of light sources is two or more. The irradiation distribution of each light source has a characteristic curve as shown in FIG. The relative light intensity (vertical axis) relative to the relative position (horizontal axis) forms a considerably steep chevron curve. By superimposing the irradiation from each light source while shifting the position, the total curve is, for example, as shown in FIG. Therefore, irradiation can be made substantially uniform in the irradiated portion 95. That is, the light from the light source 91 irradiates the upper part of the irradiated part 95 through the lens 94, similarly, the light from the light source 92 irradiates the center of the irradiated part 95, and the light from the light source 93 is irradiated with the light. The lower part of the part 95 is irradiated. As described above, by displacing the positions in the irradiated portion 95 and superimposing them, the illuminance distribution is made uniform.

FIG. 13 is a three-dimensional diagram showing an illuminance distribution of an illuminated portion when light is emitted from a light source array arranged in a plane, and this distribution diagram is confirmed by the present inventor by performing a simulation. It is. 0.016 ~ dark black
An illuminance of 0.018, followed by a dark black portion from 0.014 to 0.
016 illuminance, next dark black part is 0.012-0.01
The illuminance becomes lower as the illuminance of the display becomes lower. FIG. 12 shows a cross section of FIG. 13, in which case
The scales in both figures do not match. As shown in FIG. 1, even if the light source is a multi-lighting type or the illumination system is simplified, the illuminated portion 95 can be illuminated in a pseudo-uniform manner, resulting in a compact illumination light source.

FIG. 10 shows a second embodiment of the present invention.
FIG. 3 is a cross-sectional structural view of an illumination optical system showing the embodiment (corresponding to claim 2). In FIG. 10, two or more light sources 111 to 11
3 and at least one lens array 114 constitute an illumination system. Lights from the light sources 111 to 113 are respectively transmitted to the corresponding arrays 114a, 114b,
Irradiation is performed on the irradiated part 115 via 114c. The light source 1 is controlled by the respective arrays 114a to 114c of the lens array 114.
Light beams from 11 to 113 are applied to a part of the irradiated portion 115. Even when the light emitted from each of the light sources 111 to 113 has an intensity distribution as shown in FIG. In addition, it is possible to pseudo-uniformize the illuminance. Further, by changing the lens shape according to the position of each of the arrays 114a to 114c of the lens array 114, the uniformity of the illuminance at the irradiated portion 115 can be improved. That is, in the case of FIG. 8, the characteristics of the overall light intensity of the irradiated portion 95 in FIG. 12 are determined by the shape of one lens 94 and the emission characteristics of each of the light sources 91 to 93. In the case of, each array 1
By changing the shape of each of 14a to 114c one by one, it is possible to make the characteristics of the overall light intensity of the irradiated portion 115 in FIG. 12 more uniform.

(Third Embodiment) FIG. 11 shows a third embodiment of the present invention.
FIG. 6 is a sectional structural view (corresponding to claim 3) of an illumination optical system showing the example of (1). In FIG. 11, one lens 122 and a plurality of lamps with reflectors 121a to 121d constitute an illumination optical system. Lamp with reflector 121a-
121d are arranged in an array. The circled portion is the lamp. Each light from the lamps 121a to 121d irradiates a part of the irradiation target 123 through the lens 122. When the emitted light intensity distributions of the lamps with reflectors 121a to 121d have characteristics as shown in FIG.
At 23, they are superimposed with different peak positions. Hereinafter, this overlapping state will be described with reference to FIG. When the lamp array is composed of four lamps 121a to 121d with reflectors as shown in FIG.
The light flux from 1a is irradiated portion 123 and the intensity distribution is 131a.
(Broken line). Similarly, the lamps 121b, 121b
c and 121d are 131 in the irradiated portion 123, respectively.
b, 131c, and 131d (each indicated by a broken line). The sum of these four light intensity distributions is represented by curve 130
(Solid line). Thus, the irradiated part 123
By irradiating the luminous flux from the lamp with a shift, pseudo-uniformity of illuminance is achieved.

(Fourth Embodiment) FIGS. 1, 3 and 4
FIG. 7 is an overall perspective view of a lamp array with a reflector according to a fourth embodiment of the present invention and a sectional structural view thereof (corresponding to claims 4 and 5). In FIG. 1, 11a to 11d are reflector arrays, 12a to 12d are lamp arrays, and 13a to 13d are lamp axes. In this case, the lamp shafts 13a to 13d are all arranged in the horizontal direction. Here, FIG. 3 is an array of lamps with reflectors as viewed from the left (outside) side of FIG. 1, and FIG.
2 is an array of lamps with reflectors as viewed from the right (inside) side of FIG. Here, the solid line indicates a visible shape object, and the broken line indicates an invisible shape object. Further, lamps 10a to 10d are provided at the focal positions of the respective reflectors.

FIG. 5 is a sectional structural view of an illumination optical system using a lamp array with a parabolic reflector according to a fourth embodiment. FIG. 5 is a sectional view of the yz plane. 51 is a reflector, 52 is a lamp, 53 is a condenser lens, 54
Denotes an irradiated portion. The reflector-equipped lamp has three rows in the x direction (perpendicular to the plane of the paper) and four rows in the y direction, forming a total of 12 lamp arrays. The lamps (reflectors) are arranged at 10 mm intervals in both the x and y directions.
That is, the size of the entire reflector is 10 × in the x direction.
Since 3 = 30 mm and 10 × 4 = 40 mm in the y direction, 30 × 40 = 1200 mm ² . The condenser lens 53 is a plano-convex lens, and the radius of curvature of the curved surface is 90 m
m. The reflector has a shape of a paraboloid of revolution, and when this paraboloid of revolution is represented by the following equation (1), z = ar ² , r = √ (x ² + y ² ) (1) The quadratic coefficient a in the above equation (1) is set to 0.1. The lamp is a short arc lamp (for example, a xenon lamp, a metal halide lamp, etc.), and the distance between the arc electrodes is 1.3 m.
m. Although not shown in FIG. 5, the distance between the arc electrodes is the distance between the two electrodes present in the sphere of the lamp 52. The illuminance distribution of the irradiated portion 54 according to the present embodiment is shown in FIG. According to this configuration, the illuminance distribution of the irradiated portion 54 can be made uniform with a simple structure.

(Fifth Embodiment) FIG. 14 shows a fifth embodiment of the present invention.
FIG. 2 is a cross-sectional structural view of an illumination optical system showing the example of FIG.
FIG. 7 is an enlarged sectional view of a portion of an arc lamp array with a reflector (corresponding to claim 6). In FIG. 14, 21
Reference numerals a to 21d denote reflector arrays; 22a to 22d, arc lamp arrays; 23a to 23d, light emitted from lamps; As shown in FIG. 2, the arc lamp array with reflector is
Reference numerals 1a to 21d denote the shapes of paraboloids, and the light from the arc lamps 22a to 22d is not parallel but directed to the center of the irradiated portion 152, as shown in 23a to 23d. In this way, the light from the arc lamp array with the reflector is applied to the irradiation target 152. Since the axial direction of each of the lamp arrays 22a to 22d is inclined in the direction of converging toward the irradiated section 152, the light emitted from the four lamps is collected on the irradiated section 152 in FIG. Irradiated part 15
If the axis of each lamp is set in accordance with the size of 2, the desired area can be quasi-uniformly illuminated. In FIG. 14,
Although there are four lamp arrays, the number of arrays is two-dimensionally arranged, and the greater the total number of lamps, the easier it is to perform uniform illumination. This is because, as described above, it is easy to adjust components such as the position of each lamp and the irradiation direction for uniformity. In this embodiment, the condenser lens shown in FIG. 5 is not always necessary. For this reason, the number of parts of the illumination optical system can be reduced, and the size is further reduced.

(Sixth Embodiment) FIG. 6 is a sectional structural view (corresponding to claim 7) of an illumination optical system showing a sixth embodiment of the present invention. In FIG. 6, 61 is a reflector, 62 is a light source, 63 is a lens, 64 is a condenser lens, and 65 is an irradiated part. Two or more light sources with reflectors 62 are arranged in an array, and the shape of each of the reflectors 61 is a spheroid. A light source (eg, arc lamp) is placed at the first focal point of each spheroid reflector. Then, a lens 63 is arranged at the second focal point. Four lens arrays 63 are provided in accordance with the number of arrays of the light sources 62. FIG.
Then, immediately after the lens array 63, the condenser lens 64
However, the condenser lens 64 is not always necessary. Light from each light source (eg, arc lamp) forms an image (arc image) of the light source near the second focal point. Each of the lens arrays 63 guides this image to the irradiated section 65. Lens array 63, condenser array 64
, The illuminance distribution of the irradiated portion 65 is shown in FIG.
You can do as follows.

(Seventh Embodiment) FIG. 7 is a structural view (corresponding to claim 8) of an illumination optical system and a projection apparatus using the same according to a seventh embodiment of the present invention. The illumination optical system 81
9 shows an illumination optical system according to any one of the first to sixth embodiments of the present invention. The light emitted from the illumination optical system 81 causes the dichroic mirror 82a to separate only the visible blue light. That is, blue light is separated by a spectral characteristic having a high reflectance of a blue wavelength, which is a short wavelength, and a high transmittance of green and red in visible light. The separated blue light is reflected by the mirror 83 and is a light valve (for example, a liquid crystal element)
At 85, light intensity modulation is performed for each pixel. The light transmitted through the liquid crystal element 85 is reflected by the color combining element 87 and is
8 and projected on the screen. On the other hand, light transmitted through the dichroic mirror 82a is reflected by the next dichroic mirror 82b in green light, and red light is transmitted. The green light reflected by the dichroic mirror 82b enters a light valve (for example, a liquid crystal element) 84,
The light intensity is modulated for each pixel. The green light passing through the light valve 84 passes through the color combining element 87 and is projected on a screen via a projection lens 88.

The red light transmitted through the dichroic mirror 82b has its optical path bent by two mirrors 83, enters a light valve (for example, a liquid crystal element) 86, and is subjected to light intensity modulation for each pixel. The light transmitted through the light valve 86 is reflected by the color synthesizing element 87 and is projected on a screen via the projection lens 88. As the color synthesizing element 87, for example, a so-called dichroic prism, which is composed of four prisms and has a dichroic coating applied to a surface to be bonded can be used. Illumination optical system 81 of FIG.
By using any one of the illumination optical systems from the first embodiment to the sixth embodiment, a multi-lighting type projection display is configured. In addition, with this configuration, a compact illumination optical system can be configured in the optical axis direction without using a conventional integrator optical system (fly-eye lens system), and a miniaturized multi-turn-on projection display is realized. it can. Further, the present embodiment has an original effect of the multi-lighting type. That is, even when one lamp is cut off, the screen does not become completely dark on the screen. further,
Even if a conventional high-brightness lamp is not used, it is a multi-lighting type, so it is possible to use a plurality of low-output lamps to make the brightness the same as or higher than the conventional one despite the overall low power consumption. It is possible.

[0017]

As described above, according to the present invention,
Since the multi-lighting type illumination optical system can be made compact and the pseudo point light source of the lamp can be used, the light use efficiency is high by arranging the lamp tube so that the axial direction converges toward the irradiated part. Become. Furthermore, since the illumination optical system is a multi-lighting type, the screen does not become dark even if one lamp is cut off. By using a plurality of low-output lamps, the brightness can be reduced regardless of the overall power consumption. It can be equal to or more than the conventional one.

[Brief description of the drawings]

FIG. 1 is a sectional structural view of an illumination optical system showing a fourth embodiment of the present invention.

FIG. 2 is a sectional structural view of an illumination optical system showing a fifth embodiment of the present invention.

FIG. 3 is a front perspective view of the entire parabolic reflector array showing a fourth embodiment of the present invention.

FIG. 4 is a rear perspective view of the entire parabolic reflector array showing a fourth embodiment of the present invention.

FIG. 5 is a sectional structural view of an illumination optical system showing a fourth embodiment of the present invention.

FIG. 6 is a sectional structural view of an illumination optical system showing a sixth embodiment of the present invention.

FIG. 7 is a configuration diagram of a multi-lighting type projection display apparatus according to a seventh embodiment of the present invention.

FIG. 8 is a sectional structural view of an illumination optical system showing a first embodiment of the present invention.

FIG. 9 is a characteristic curve diagram showing an intensity distribution of light emitted from each light source.

FIG. 10 is a sectional structural view of an illumination optical system showing a second embodiment of the present invention.

FIG. 11 is a sectional structural view of an illumination optical system showing a third embodiment of the present invention.

FIG. 12 is a characteristic curve diagram in a state where light from a plurality of lamps is superimposed on an irradiated portion.

FIG. 13 is a three-dimensional intensity distribution diagram (simulation result of FIG. 5) in a state in which light from a plurality of planar light sources is superimposed on an irradiated portion.

FIG. 14 is a sectional structural view of an illumination optical system showing a fifth embodiment of the present invention.

[Explanation of symbols]

11a to 11d ... reflector array, 12a to 12d ...
Lamp array, 13a to 13d ... axis of lamp, 21a to
21d reflector array, 22a-22d lamp array, 23a-23d lamp axis, 51, 61 reflector array, 52, 62 lamp array, 53, 64
... condenser lens, 63 ... fly-eye lens, 54,
65: irradiated part, 81: illumination optical system, 82a, 82b ...
Dichroic mirror, 83: mirror, 84: light valve (green), 85: light valve (blue), 86: light valve (red), 87: color combining element, 88: projection lens,
91 to 93: light source, 94: lens, 95: irradiated part, 1
11 to 113: light source, 114a to 114c: lens array, 115, 123: irradiated portion, 121a to 121d:
Lamp, 130: sum of light intensity distributions, 131a to 131
d: intensity distribution of lamps 121a to 121d, 21a to 2
1d: reflector; 23a to 23d: optical axis from lamp array; 22a to 22d: arc lamp array with reflector; 152: irradiated part.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G02F 1/13357 G02F 1/1335 530 G03B 21/14 // F21Y 101: 00 F term (reference) 2H042 DD01 DD05 DE04 2H088 EA15 HA13 HA21 HA24 HA25 HA28 MA20 2H091 FA05Z FA14Z FA26Z FA29Z FA41Z LA11 LA15 LA18 MA07 3K042 AA01 AC04 AC06 BB03 BB06 BC01 BC02 BC08 BE08

Claims (8)

[Claims] 1. A light source comprising at least two light sources and at least one lens, wherein each light source irradiates a part of an illuminated part through the lens, so that all the light sources become the whole of the illuminated part. An illumination optical device characterized by irradiating light. 2. An illumination device comprising two or more light sources and at least one lens array, irradiating light from each light source to a portion to be irradiated via a corresponding array of the one lens array. An illumination optical device characterized in that irradiation is performed by shifting a position in an irradiation unit. 3. The illumination optical device according to claim 1, wherein the light sources are arranged in an array, and the same number of reflectors as the number of light sources are arranged in an array. The illumination optical device is characterized in that a total intensity distribution is obtained by irradiating the irradiation light at a portion to be irradiated. 4. The illumination optical device according to claim 3, wherein the reflectors arranged in an array have a shape of a paraboloid of revolution. 5. The illumination optical device according to claim 1, wherein an arc lamp is used as the light source. 6. An illuminating optical device wherein two or more arc lamps with reflectors are arranged in an array, and the axial direction of each of the lamps with reflectors is arranged in a direction converging toward a portion to be irradiated. . 7. Two or more light sources with reflectors are arranged in an array, each reflector having a spheroidal shape, and each light source is arranged near a first focal point of a corresponding reflector, and each second light source is arranged. An illumination optical device, wherein each of the lens arrays is arranged in the illumination optical system. 8. A light source, an illumination optical system for irradiating an illuminated portion from the light source, and a light combining device that separates light output from the illumination optical system into respective colors of blue, green, and red, and then modulates the light intensity of each color. 8. A projection display apparatus comprising: an image forming unit that reflects light at an angle; and a projection optical system, wherein the light source and the illumination optical system are used.
A projection device using the illumination optical device according to any one of the above.