JP2008014983A - Projection type display device and back projection type display device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection type display device achieving higher luminance and miniaturization when using a plurality of lamp parts. <P>SOLUTION: The second focus of the ellipsoidal reflector of the plurality of lamp parts formed of the ellipsoidal reflector and a light source arranged on the first focus of the ellipsoidal reflector is aligned with the focus of a parabolic reflector that is a light composing part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projection display device and a rear projection display device using a plurality of lamp units.

  In the following Patent Document 1, a first light source, n other light sources whose emission optical axes are orthogonal to the emission optical axis of the first light source, and other distances corresponding to the distance from the first light source. N reflectors that totally reflect the outgoing light beams of the other light sources in a direction perpendicular to the light source at a position away from the light source, and the outgoing optical axis of the first light source or the reflected optical axis of each reflector and the outgoing optical axis of each other light source And a Σn number of half mirrors that reflect a part of the incident light in a right angle direction and transmit the other part of the incident light.

JP-A-6-208080

  In Patent Document 1, when a plurality of light sources are used, since the Σn half mirrors are used, the entire projection display device is enlarged. Further, with the above configuration, the light beams emitted from the first light source and each of the other light sources are equally dispersed to obtain a plurality of emitted light beams having the same luminance and chromaticity. Not considered.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a projection display device capable of achieving high brightness and downsizing when a plurality of lamp units are used. is there.

  One aspect of the present invention is a second focal point of an elliptical reflector of a plurality of lamp portions formed by an elliptical reflector and a light source disposed on the first focal point of the elliptical reflector; The focal point of the parabolic reflector, which is the photosynthesis unit, is matched.

  It is possible to provide a projection display device and a rear projection display device that can be reduced in size with high brightness.

  Embodiments will be described below with reference to the drawings. In each figure, elements having common functions are denoted by the same reference numerals, and description of elements once described is omitted.

  FIG. 1 is a schematic view of a projection type display device showing Embodiment 1. As shown in FIG. Reference numeral 3A denotes a first lamp unit, which is formed by a light source 1A and an ellipsoidal reflector 2A, and the light source 1A is disposed at a first focal position of the reflector 2A. 3B is a 2nd lamp | ramp part, it is similarly formed from the light source 1B and the ellipsoidal reflector 2B, and the light source 1B is arrange | positioned in the 1st focus position of the reflector 2B. A unit formed by at least the first lamp unit and the second lamp unit is referred to as a lamp unit. For ease of understanding, the light source is indicated by a dot, and the reflector is indicated only by a reflecting surface. Reference numeral 4 denotes a photosynthesis unit having a parabolic reflecting surface 4C, and an integrator 67 having two lens arrays, the first lens array 6 and the second lens array 7. The integrator 67 may be a light pipe. 8 is a polarization conversion element, 9 is a condenser lens, 10R and 10G are condenser lenses, 11R, 11G and 11B are image display elements, 201 is a first dichroic mirror, 202 is a second dichroic mirror, 203, 204 and 205. Is a total reflection mirror, 206 is a first relay lens, 207 is a second relay lens, 208 is a third relay lens, 209R, 209G and 209B are incident side polarizing plates, 210R, 210G and 210B are outgoing side polarizing plates, and 211 is A dichroic prism 212 serving as a color composition unit is a projection lens. Here, the symbol R indicates a red element, G indicates a green element, and B indicates a blue element.

  The lights emitted from the light sources 1A and 1B are reflected by the reflectors 2A and 2B, respectively, and enter the light combining unit 4. At this time, the lamp units 3A and 3B are arranged so that the second focal positions of the reflectors 2A and 2B and the focal position (P) of the reflecting surface 4C of the light combining unit 4 coincide. By arranging in this way, light emitted from the light sources 1A and 1B at the first focal positions of the ellipsoidal reflectors 2A and 2B is reflected by the ellipsoidal reflectors 2A and 2B, respectively. , 2B and then incident on the reflecting surface 4C of the light combining unit 4. Thereafter, the light reflected by the reflecting surface 4C of the light combining unit 4 is converted into parallel light and is incident on the first lens array 6 on the optical axis extension of the combining unit 4. That is, the light emitted from the lamp units 3A and 3B is combined by the light combining unit 4 to become parallel light.

  The positions of the lamp units 3A and 3B may be other than the planar arrangement as shown in the figure as long as the second focal position coincides with the focal point P of the light combining unit 4 and does not block the light 401 from the light combining unit 4. Good. Here, the light source unit 5 is used until it enters the first lens array 6.

  The light incident on the first lens array 6 divides the light incident on the first lens array 6 into light from a plurality of lens cells 63 arranged in a matrix, and the light illuminance is efficiently and substantially uniform. And is guided so as to pass through the second lens array 7 and the polarization conversion element 8. At this time, the light incident from the second lens array 7 by the polarization conversion element 8 is aligned with a predetermined polarization. The light emitted from the polarization conversion element 8 is transmitted through the condenser lens 9, and then the R light is reflected by the first dichroic mirror 201, which is a first color separation unit disposed at an inclination of 45 degrees with respect to the optical axis. G light and B light are transmitted. The R light is reflected by the total reflection mirror 203 and then converted into parallel light by the condenser lens 10R. Unnecessary polarized light is removed (absorbed) by the incident-side polarizing plate 209R and then incident on the image display element 11R to be superimposed. To do.

  On the other hand, the B light and G light transmitted through the first dichroic mirror 201 are incident on the second dichroic mirror 202 which is the second color separation unit. The G light is reflected by the second dichroic mirror 202, and unnecessary polarized light is removed (absorbed) by the incident-side polarizing plate 209G, and then incident on the image display element 11G to form a superimposed image.

  Further, the B light transmitted through the second dichroic mirror 202 is transmitted through the first relay lens 206, and its optical path is bent by 90 ° by the B light total reflection mirror 204 and transmitted through the second relay lens 207. The optical path is bent by 90 ° by the light total reflection mirror 205, and parallel light is obtained by the third relay lens 208 provided in front of the image display element. Thereafter, unnecessary polarized light is removed (absorbed) by the incident-side polarizing plate 209B, and then incident on the transmissive image display element 11B to form a superimposed image.

  In the video display elements 11R, 11G, and 11B, each liquid crystal cell that forms each pixel of the video display elements 11R, 11G, and 11B according to a video signal (not shown) applied from a drive circuit (not shown). The polarization direction changes, and the light finally having a direction that coincides with the polarization direction of the output-side polarizing plates 210R, 210G, and 210B passes through the output-side polarizing plates 210R, 210G, and 210B and is emitted and enters the dichroic prism 211. To do. Further, the light orthogonal to the polarization direction is absorbed by the output side polarizing plates 210R, 210G, and 210B and does not enter the dichroic prism 211. In this way, light intensity modulation that changes the light intensity according to the video signal input from the outside is performed, and an image that is an optical image is formed.

  The dichroic prism 211 reflects R light and B light, transmits G light, synthesizes colors, and emits them to the projection lens 212. The projection lens 212 enlarges and projects the image synthesized by the dichroic prism 211 on the screen 213.

  FIG. 2 is a diagram of the integrator 67 as seen from the incident direction. As shown in the figure, the horizontal size 671 and the vertical size 672 of the lens cell 63 (73) of the integrator 67 may be the same as or slightly larger than the effective area 401 of the photosynthesis unit 4, and therefore the horizontal size of the lens cell 63 (73). 671 and the vertical size 672 can be made the same. Therefore, the condensing lens 9 can be made small, and subsequent optical components and the like can be miniaturized, which is advantageous for miniaturization of the projection display device.

  Next, Example 2 will be described. FIG. 3 is a schematic diagram of the light source unit 5 showing the second embodiment. Example 2 is the same as Example 1 after the first lens array 6 and is omitted.

  In FIG. 3, 3A is a 1st lamp | ramp part, and it is formed from the light source 1A and the ellipsoidal reflector 2A, and the light source 1A is arrange | positioned in the 1st focus position of the reflector 2A. 3B is a 2nd lamp | ramp part, it is similarly formed from the light source 1B and the ellipsoidal reflector 2B, and the light source 1B is arrange | positioned in the 1st focus position of the reflector 2B. 3C is a 3rd lamp part, and is formed from the light source 1C and the parabolic reflector 2C, and the light source 1C is arrange | positioned in the focus position of the reflector 2C. As in the first embodiment, for the sake of easy understanding, only the point is shown for the light source and only the reflecting surface is shown for the reflector.

  As shown in the figure, the second focal points of the reflectors 2A and 2B are aligned with the position of the light source 1C, and the optical axis of the reflector 2C is arranged to be perpendicular to the first lens array 6. The light emitted from the lamp units 3A and 3B is collected at the position of the light source 1C, and then reflected by the reflector 2C to become parallel light and enter the first lens array 6. Further, the light from the light source 1 </ b> C is also converted into parallel light by the reflector 2 </ b> C and enters the first lens array 6. That is, the reflector 2C has the same function as that of the light combining unit 4C of the first embodiment and also functions as a reflector that emits light from the light source 1C as parallel light.

  As described above, in the second embodiment, it is possible to easily add one light source as compared with the first embodiment, which is advantageous for further increasing the brightness, and similarly to the first embodiment, The condensing lens 9 can be made small, and the subsequent optical components can be miniaturized, which is advantageous for miniaturization of the projection display device.

  Next, Example 3 will be described. FIG. 4 is a schematic diagram of the light source unit 5 showing the third embodiment. The third embodiment is the same as the first embodiment after the first lens array 6 and will be omitted.

  Reference numeral 3A denotes a first lamp unit, which is formed of a light source 1A and an ellipsoidal reflector 2A, and the light source 1A is disposed at a first focal position of the reflector 2A. 3B is a 2nd lamp | ramp part, it is similarly formed from the light source 1B and the ellipsoidal reflector 2B, and the light source 1B is arrange | positioned in the 1st focus position of the reflector 2B. As in the first embodiment, for the sake of clarity, the light source is indicated by a dot, and the reflector is indicated only by a reflecting surface. Reference numeral 43 denotes a light combining unit having an elliptical reflecting surface 43C, and the first focal point of the reflecting surface 43C is P2. Reference numeral 44 denotes a concave lens.

  The lights emitted from the light sources 1A and 1B are reflected by the reflectors 2A and 2B, respectively, and enter the light combining unit 43. At this time, the lamp units 3A and 3B are arranged so that the second focal point P2 of each reflector 2A and 2B and the first focal position P2 of the reflecting surface 43C of the light combining unit 43 coincide. By arranging in this way, light emitted from the light sources 1A and 1B at the first focal positions of the ellipsoidal reflectors 2A and 2B is reflected by the ellipsoidal reflectors 2A and 2B, respectively. , 2B and then incident on the reflecting surface 43C of the light combining unit 43. Thereafter, the light reflected by the reflecting surface 43C of the light combining unit 43 is condensed toward a second focal point (not shown) of the reflecting surface 43C, and is converted into parallel light by the concave lens 44, and is reflected on the first lens array 6. Incident.

  In the third embodiment described above, similarly to the first embodiment, the light emitted from the first lamp unit and the second lamp unit can be combined and made incident on the first lens array 6, and further the light synthesis can be performed. Since the light emitted from the portion 43 is condensed toward the first lens array direction, there is an advantage that the degree of freedom of the arrangement positions of the lamp portions 3A and 3B increases.

  Next, Example 4 will be described. FIG. 5 is a schematic diagram of the light source unit 5 showing the fourth embodiment. The fourth embodiment is the same as the first embodiment after the first lens array 6 and is omitted.

  Reference numeral 3A denotes a first lamp unit, which is formed of a light source 1A and an ellipsoidal reflector 2A, and the light source 1A is disposed at a first focal position of the reflector 2A. 3B is a 2nd lamp | ramp part, it is similarly formed from the light source 1B and the ellipsoidal reflector 2B, and the light source 1B is arrange | positioned in the 1st focus position of the reflector 2B. As in the first embodiment, for the sake of clarity, the light source is indicated by a dot, and the reflector is indicated only by a reflective surface. Reference numeral 4 denotes a light combining unit having a parabolic reflecting surface 4C, 45 and 46 are total reflection mirrors, and 6 is a first lens array.

  The light emitted from the lamp units 3 </ b> A and 3 </ b> B is reflected by the total reflection mirrors 45 and 46 and enters the light combining unit 4.

  The light incident on the light combining unit 4 is converted into parallel light by the reflecting surface 4 </ b> C of the light combining unit 4 and is incident on the first lens array 6. The subsequent steps are the same as in the first embodiment.

  In the fourth embodiment described above, as in the first embodiment, the projection display device can be reduced in size and the degree of freedom of the arrangement positions of the lamp portions 3A and 3B is increased. There is an advantage that the members (not shown) for holding the lamp units 3A and 3B and the light combining unit 4 can be easily designed by making the optical axes of the units 3A and 3B and the light combining unit 4 parallel to each other.

  Next, Example 5 will be described. FIG. 6 is a schematic diagram of the light source unit 5 showing the fifth embodiment. The fifth embodiment is the same as the first embodiment after the first lens array 6 and will be omitted.

  In FIG. 6, 3A is a first lamp unit, which is formed from a light source 1A, a parabolic reflector 21A, and a condenser lens 20A that condenses the light reflected by the reflector 21A at the second focal point of the reflector 21A. The light source 1A is arranged at the first focal position of the reflector 21A. Similarly, 3B is a 2nd lamp | ramp part, and is formed from the condensing lens 20B which condenses the light reflected by the light source 1B, the parabolic reflector 21B, and the reflector 21B to the 2nd focus of the reflector 21B. The light source 1B is disposed at the first focal position of the reflector 21B. Reference numeral 43 denotes a light combining unit having a parabolic reflecting surface 43C, and the focal point of the reflecting surface 43C is P2. As in the first embodiment, for the sake of easy understanding, only the point is shown for the light source and only the reflecting surface is shown for the reflector.

  The lights emitted from the light sources 1A and 1B are reflected by the reflectors 21A and 21B, respectively, and enter the light combining unit 43. At this time, the condenser lenses 20A and 20B are arranged so that the light reflected by the reflectors 21A and 21B is condensed at P2. By arranging in this way, the light emitted from the light sources 1A and 1B at the focal positions of the parabolic reflectors 21A and 21B is reflected by the parabolic reflectors 21A and 21B, respectively. After condensing at the focal point P of 21B, it enters the reflecting surface 43C of the light combining unit 43. Thereafter, the light reflected by the reflecting surface 43 </ b> C of the light combining unit 43 is converted into parallel light and is incident on the first lens array 6.

  In the fifth embodiment described above, similarly to the first embodiment, the light emitted from the first lamp unit and the second lamp unit are combined and made incident on the first lens array 6. Can be miniaturized.

  Similarly to the third embodiment, when the light combining unit 43 has an elliptical shape, P2 is arranged at the first focal point of the elliptical shape, the concave lens 44 is arranged, and light is applied to the first lens array 6. By making the light incident, it is possible to obtain the same effect as in the third embodiment. Needless to say, when the light source is arranged at P2, it is advantageous to further increase the luminance as in the second embodiment.

  In the first to fifth embodiments, the case where the number of the lamp units forming the lamp unit is two has been described. However, even when the number of the lamp units is three or more, the second focal position of the reflectors of all the lamp units is used as the focal position of the light combining unit. If it arrange | positions so that it may correspond, a brightness | luminance can be raised according to the number of lamp | ramp parts, without changing the optical system after a 1st lens array. In the first to fifth embodiments, the case where three transmissive image display elements are used has been described. However, one transmissive image display element or reflective image display element is used. Needless to say, the same effect can be obtained. Needless to say, the projection display devices of Examples 1 to 5 are also applicable to a rear projection display device that projects an image from the back of the screen after being folded by an optical path folding mirror.

1 is a schematic diagram of a projection display device according to Embodiment 1. FIG. The figure which looked at the integrator of Drawing 1 from the entrance plane. FIG. 6 is a schematic diagram illustrating a light source unit according to a second embodiment. FIG. 6 is a schematic diagram illustrating a light source unit according to a third embodiment. FIG. 6 is a schematic diagram illustrating a light source unit according to a fourth embodiment. FIG. 6 is a schematic diagram illustrating a light source unit according to a fifth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light source, 2 Reflector, 3 Lamp part, 4 Light composition part, 5 Light source unit, 6 1st lens array, 7 2nd lens array, 8 Polarization conversion element, 9 Condensing lens, 10 Condenser lens, 11 Video display element , 20 condenser lens, 21 reflector, 67 lens array group, 201 first dichroic mirror, 202 second dichroic mirror, 203 total reflection mirror, 204 total reflection mirror, 205 total reflection mirror, 206 first relay lens, 207 2nd relay lens, 208 3rd relay lens, 209 Incident side polarizing plate, 210 Outgoing side polarizing plate, 211 Dichroic prism, 212 Projection lens.

Claims (10)

A plurality of lamp portions formed by an ellipsoidal reflector and a light source disposed on a first focal point of the ellipsoidal reflector;
A light combining unit that is formed of a parabolic reflector and combines light from the plurality of lamp units, wherein a second focal point of the elliptical reflector and a focal point of the parabolic reflector are A photosynthesis unit arranged at a matching position;
An integrator for equalizing the illuminance of light from the photosynthesis unit;
A polarization conversion element that aligns the polarization direction of the light from the integrator;
A video display element that modulates light from the polarization conversion element into a video signal corresponding to an optical image;
A projection display device, comprising: a projection lens that projects light from the image display element. A plurality of lamp portions formed by an ellipsoidal reflector and a light source disposed on a first focal point of the ellipsoidal reflector;
A light combining unit that is formed of an elliptical reflector and combines light from the plurality of lamp units, the second focal point of the elliptical reflector of the lamp unit and the focal point of the elliptical reflector A photosynthesis unit arranged at a position where and match,
A concave lens that collimates the light from the photosynthesis unit;
An integrator for uniformizing the illuminance of light from the concave lens;
A polarization conversion element that aligns the polarization direction of the light from the integrator;
A video display element that modulates light from the polarization conversion element into a video signal corresponding to an optical image;
A projection display device, comprising: a projection lens that projects light from the image display element. A plurality of parabolic reflectors, a light source disposed on a focal point of the parabolic reflector, and a condensing lens that collects light reflected by the parabolic reflector. Lamp part of
A light combining unit that is formed of a parabolic reflector and combines light from the plurality of lamp units, the light collecting position of the light from the plurality of lamp units and the parabolic shape A photosynthesis unit arranged at a position where the focal point of the reflector coincides;
An integrator for equalizing the illuminance of light from the photosynthesis unit;
A polarization conversion element that aligns the polarization direction of the light from the integrator;
A video display element that modulates light from the polarization conversion element into a video signal corresponding to an optical image;
A projection display device, comprising: a projection lens that projects light from the image display element. A plurality of parabolic reflectors, a light source disposed on a focal point of the parabolic reflector, and a condensing lens that collects light reflected by the parabolic reflector. Lamp part of
A light combining unit that is formed of an ellipsoidal reflector and combines light from the plurality of lamp units, the light collecting position of the light from the plurality of lamp units and the ellipsoidal reflector A photosynthesis unit arranged at a position where the first focal point coincides;
A concave lens that collimates the light from the photosynthesis unit;
An integrator for uniformizing the illuminance of light from the concave lens;
A polarization conversion element that aligns the polarization direction of the light from the integrator;
A video display element that modulates light from the polarization conversion element into a video signal corresponding to an optical image;
A projection display device, comprising: a projection lens that projects light from the image display element. A projection type display device according to any one of claims 1 to 4,
A projection display device, wherein a light source is disposed at a focal position of the light combining unit. A projection display device according to any one of claims 1 to 5,
The integrator is formed of a first lens array and a second lens array. A projection display device according to any one of claims 1 to 5,
The projection display device, wherein the integrator is a light pipe. A projection type display device according to any one of claims 1 to 7,
The plurality of lamp parts are formed of a first lamp part and a second lamp part,
The projection display device, wherein the first lamp unit and the second lamp unit are arranged symmetrically with respect to an optical axis of the light combining unit. A projection type display device according to any one of claims 1 to 8,
A projection display device, wherein a reflection mirror is disposed between the plurality of lamp units and the light combining unit. A projection display device according to any one of claims 1 to 9,
A folding mirror that folds the optical path of the light from the projection display device;
A rear projection display device having a screen for displaying light from the folding mirror.

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