JP2014062985A - Projection type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projection type display device that is able to downsize the device without degrading light use efficiency.SOLUTION: A projection type display device 1 comprises a light valve 121, a projection optical system 124, a plurality of excitation light sources 11 to 73, light reflection elements 81 to 87, and phosphor element 100G. The light reflection faces of the light reflection elements 81 to 87 reflect a plurality of luminous fluxes, emitted from the excitation light sources 11 to 73, in a lateral direction and in a direction away from the optical axis OA of the projection optical system 124. The height of the light reflection elements 81 to 87 from the excitation light sources 11 to 73 of the light reflection faces decrease as they approach the optical axis OA of the projection optical system 124. The light valve 121 is arranged higher than the ends of the light reflection elements 81 to 87 on the optical axis OA side and in a position where it laterally overlaps the light reflection elements.

Description

  The present invention relates to a projection display device including a plurality of light sources.

  A projection display device, also called a projector, is a light valve that spatially modulates incident light, a light source system, an illumination optical system that guides light emitted from the light source system to the light valve, and is transmitted or transmitted by the light valve. A projection optical system for enlarging and projecting the reflected modulated light on the screen. Conventionally, a lamp light source such as a high-pressure mercury lamp or a xenon lamp has been mainly used as a high-intensity light source for a projection display device. However, since the lamp light source has a short lifetime and a high frequency of maintenance management, there is a disadvantage that the running cost is high.

  Therefore, in recent years, a projection display device has been developed that uses a semiconductor light emitting element such as a light emitting diode (LED) or a laser diode (LD) as a light source. Here, since the individual luminances of the semiconductor light emitting elements such as LEDs and LDs are lower than the luminance of the lamp light source, it is necessary to increase the luminance of the light source system by using a plurality of semiconductor light emitting elements. Such a projection display device using a plurality of semiconductor light emitting elements as light sources is disclosed in, for example, Patent Document 1 (Japanese Patent Laid-Open No. 2011-13317) and Patent Document 2 (Japanese Patent Laid-Open No. 2011-95388). Yes.

  Patent Document 1 discloses a projector including a light source unit including a plurality of light sources arranged in a planar shape. The light source unit includes a light source group composed of a plurality of light sources arranged in a plane so as to form rows and columns, and a light beam emitted from the plurality of light sources and having a reduced cross-sectional area in the column direction. And a second reflecting mirror group that converts a light beam reflected by the first reflecting mirror group into a light beam having a reduced cross-sectional area in the row direction. By using the first reflecting mirror group and the second reflecting mirror group, it is possible to generate a high-luminance light beam having a small cross-sectional area in the column direction and the row direction, and thus the light use efficiency is high.

  On the other hand, Patent Document 2 also discloses a projector including a light source unit including a plurality of light sources. A light source unit disclosed in Patent Document 2 includes an excitation light irradiation device including a plurality of blue laser diodes (excitation light sources) arranged in a matrix, and a reflection mirror that converts the direction of emitted light of the excitation light irradiation device. And a phosphor wheel that emits light in the green wavelength band using the light reflected by the reflecting mirror group as excitation light, a blue light source device, and a red light source device. Here, the reflection mirror group is composed of a plurality of reflection mirrors arranged in a staircase pattern, and these reflection mirrors are arranged so as to reduce the cross-sectional area of incident light in one direction.

JP 2011-13317 A (FIG. 1 and paragraphs 0027 to 0037, etc.) Japanese Patent Laying-Open No. 2011-95388 (FIG. 3, paragraphs 0041 to 0052, etc.)

  In recent years, in the market of projection display devices, not only high brightness of the light source system but also miniaturization of the device (housing) has been strongly demanded. In the projectors disclosed in Patent Documents 1 and 2, the projection-side optical system (projection optical system) that projects the modulated light emitted from the DMD onto the screen is disposed at a position adjacent to the light source unit in the lateral direction. Therefore, there has been a limit to miniaturization of the apparatus.

  In view of the above, an object of the present invention is to provide a projection display device that can realize downsizing of the device without impairing light utilization efficiency.

  A projection display device according to an aspect of the present invention includes a light valve that spatially modulates an incident light beam to generate modulated light, and a projection that enlarges and projects an optical image represented by the modulated light onto an external projection surface. An optical system, an excitation light source group composed of a plurality of light sources arranged along a horizontal direction intersecting the optical axis direction of the projection optical system, and a single or a plurality of lights facing the light emitting ends of the plurality of light sources A light-reflecting element having a reflecting surface; a phosphor element that absorbs and emits light reflected by the light-reflecting surface as excitation light; and light guide optics that guides the fluorescent light emitted from the phosphor element to the light valve. The light reflecting surface of the light reflecting element reflects the plurality of light beams emitted from the plurality of light sources in the lateral direction and in a direction away from the optical axis of the projection optical system, and the excitation The height of the light reflecting surface from the light source group is the projection height. The light valve becomes smaller as it approaches the optical axis of the optical system, and the light valve is disposed at a position higher than the optical axis side end of the projection optical system in the light reflecting element, and the light reflecting element and the lateral direction It arrange | positions in the position which overlaps in.

  According to the present invention, the height between the light reflecting surface of the light reflecting element and the excitation light source group decreases as it approaches the optical axis of the projection optical system. An optical path that does not interfere with the element can be secured. Therefore, the light valve can be arranged at a position overlapping the end portion of the light reflecting element in the lateral direction without contacting the light reflecting element. Thereby, the horizontal width of the projection display device can be made compact. Therefore, it is possible to reduce the size of the projection display device without impairing the light utilization efficiency.

1 is a diagram schematically showing a main configuration of a projection display apparatus according to Embodiment 1 of the present invention. 2 is a diagram showing a schematic configuration of an excitation light source unit according to Embodiment 1. FIG. 3 is a perspective view showing an example of a light intensity uniformizing element according to Embodiment 1. FIG. It is a figure which shows schematically a part of structure of the projection type display apparatus of Embodiment 1 when it sees from the front side (X-axis negative direction side). It is a figure which shows roughly the main structures of the projection type display apparatus of Embodiment 2 which concerns on this invention. It is a figure which shows roughly arrangement | positioning of the bending mirror of Embodiment 2, and a concave mirror. It is a figure which shows roughly the main structures of the projection type display apparatus which is a modification of Embodiment 2. FIG. It is a figure which shows roughly the main structures of the projection type display apparatus of Embodiment 3 which concerns on this invention. It is a figure which shows schematic structure of the excitation light source unit and condensing lens group of Embodiment 3 when it sees from the front side (X-axis negative direction side). It is a figure which shows schematically a part of structure of the projection type display apparatus of Embodiment 3 when it sees from the front side (X-axis negative direction side). It is a figure which shows roughly the main structures of the projection type display apparatus of Embodiment 4 which concerns on this invention. It is a figure which shows schematic structure of the excitation light source unit of Embodiment 4 when it sees from the bottom face side (Y-axis negative direction side). It is a figure which shows schematic structure of the excitation light source unit and condensing lens group of Embodiment 4 when it sees from the front side (X-axis negative direction side). It is a figure which shows schematically a part of structure of the projection type display apparatus of Embodiment 4 when it sees from the front side (X-axis negative direction side). It is a figure which shows roughly the main structures of the projection type display apparatus of Embodiment 5 which concerns on this invention. It is a figure which shows schematically a part of structure of the projection type display apparatus of Embodiment 5 when it sees from the front side (X-axis negative direction side).

  Hereinafter, various embodiments according to the present invention will be described with reference to the drawings. In all the drawings, components having similar configurations and functions are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate so as not to overlap.

Embodiment 1 FIG.
FIG. 1 is a diagram schematically showing the main configuration of a projection display apparatus 1 according to Embodiment 1 of the present invention. As shown in FIG. 1, the projection display apparatus 1 includes a housing 2 that forms an outer frame. Inside the housing 2, a control unit 3, an excitation light source unit 100 </ b> E, a phosphor element 100 </ b> G, red A light source 100R, a blue light source 100B, color separation filters 94 and 111, a light intensity equalizing element 113, a relay lens group 115, a bending mirror 120, a light valve 121, and a projection optical system 124 are provided.

  The X-axis direction, Y-axis direction, and Z-axis direction in FIG. 1 are orthogonal to each other. Here, the X-axis direction is parallel to the optical axis OA of the projection optical system 124, the Y-axis direction is parallel to the height direction of the projection display device 1, and the Z-axis direction is the projection display device 1. It is parallel to the horizontal width direction.

  The light valve 121 is a spatial modulation of the light beam incident from the condenser lens 122, that is, a two-dimensional or three-dimensional property of the incident light beam (for example, phase, polarization state, intensity, or propagation direction). This is a reflective spatial light modulator that performs variable control. The control unit 3 generates a modulation control signal MC based on the image signal VS supplied from an external signal source (not shown), and supplies this modulation control signal MC to the light valve 121. The light valve 121 can generate and output modulated light representing an optical image by spatially modulating the incident light beam according to the modulation control signal MC. In the present embodiment, a digital micromirror device (DMD: registered trademark) is used as the light valve 121, but is not limited to this. Note that, for example, a reflective liquid crystal element can be used instead of the DMD.

  The projection optical system 124 refracts the modulated light emitted from the light valve 121 and emits projection light (image light) from the front surface 124f. The projection optical system 124 can enlarge and project the optical image represented by the modulated light onto the projection surface 150 of the external screen.

  The excitation light source unit 100E includes a plurality of excitation light sources 11 to 13, 21 to 23, 31 to 33, 41 to 43, 51 to 53, 61 to 63, 71 to 73 (hereinafter “ A plurality of pumping light sources 11-13, 21-23, 31-33, 41-43, 51-53, 61-63, 71-73 emitted in the positive direction of the Y-axis. And collimating lenses 15 to 17, 25 to 27, 35 to 37, 45 to 47, 55 to 57, 65 to 67, and 75 to 77 (hereinafter also referred to as “collimating lens group”) that collimate the light flux of the book. have. As the excitation light sources 11 to 13, 21 to 23, 31 to 33, 41 to 43, 51 to 53, 61 to 63, 71 to 73, for example, laser light in a blue wavelength region (oscillation wavelength: about 450 nm) is output. A plurality of blue laser diodes (blue LD: Blue Laser Diode) may be used.

  FIG. 2 is a diagram showing a schematic configuration of the excitation light source unit 100E when viewed from the front side (X-axis negative direction side) of the projection display device 1. As shown in FIG. As shown in FIGS. 1 and 2, the excitation light sources 11 to 13, 21 to 23, 31 to 33, 41 to 43, 51 to 53, 61 to 63, and 71 to 73 are arranged in three rows 7 in the XZ plane. They are arranged in rows and columns in a matrix. The collimating lens group emits a collimated light beam in the positive Y-axis direction. As shown in FIG. 2, the excitation light source unit 100 </ b> E includes a light reflecting element 80 including plate-like light reflecting mirrors 81 to 87 on which a collimated light beam is incident. The light reflecting mirrors 81 to 87 each have a light reflecting surface facing the light emitting end of the excitation light source group. These light reflecting mirrors 81 to 87 reflect a light beam incident on the light reflecting surface at an incident angle of about 45 ° in the lateral direction (Z-axis negative direction) and emit it toward the condenser lens group 90. Therefore, the light reflecting mirrors 81 to 87 bend the optical path of the light flux by about 90 °. The light reflecting surfaces of the light reflecting mirrors 81 to 87 are preferably formed of a silver coating layer in order to efficiently reflect blue light.

  As shown in FIG. 2, the incident angle of the light to the light reflecting element 80 is about 45 °, and the light beam reflected by the light reflecting element 80 is substantially parallel to the optical axis of the condenser lens group 90. Although it progresses in a direction, it is not limited to this. For example, the incident beam group to the light reflecting element 80 is condensed by increasing the incident angle of the light to the light reflecting mirrors 81 to 87 as the distance from the excitation light source group is smaller and closer to the excitation light source group. It can be reflected in a direction approaching the optical axis of the lens group 90. For example, the incident angle of light to the light reflecting mirror 84 disposed on the optical axis of the condenser lens group 90 is about 45 °, the incident angle of light to the light reflecting mirror 81 is smaller than 45 °, and The incident angle of light to the light reflecting mirror 87 may be made larger than 45 °. Thereby, the cross-sectional diameter of the light beam group incident on the condensing lens group 90 can be reduced, and the light condensing efficiency to the phosphor element 100G can be improved. Further, since the light beam incident on the periphery of the condensing lens group 90 is easily affected by spherical aberration, the light beam group incident on the condensing lens group 90 is collected in a region near the optical axis of the condensing lens group 90. Thereby, it is possible to increase the light collection efficiency to the phosphor element 100G while reducing the influence of the spherical aberration.

  The height of the light reflecting surfaces of the light reflecting mirrors 81 to 87 from the excitation light source group decreases as the distance from the optical axis OA of the projection optical system 124 decreases, and increases as the distance from the optical axis OA of the projection optical system 124 increases. In addition, the light reflecting mirrors 81 to 87 are arranged in a step shape. Therefore, as shown in FIG. 2, the intervals between the plurality of light beams reflected by the light reflecting mirrors 81 to 87 are narrower than the intervals between the plurality of light beams emitted from the excitation light source group.

  The condensing lens group 90 includes a biconvex lens 91 and a biconcave lens 92, condenses the collimated light beam incident from the light reflecting element 80, and cross-sectional diameters of the light beam (dimensions in the X axis direction and the Y axis direction). Is reduced and converted to a substantially parallel light beam again. The light beam emitted from the condenser lens group 90 passes through the color separation filter 94 and the condenser lens group 104 and then enters the phosphor element 100G. The color separation filter 94 has an optical characteristic of transmitting incident light in the blue wavelength region and red wavelength region and reflecting the incident light in the green wavelength region without transmitting it. For example, the color separation filter 94 can be configured by a dichroic mirror having a dielectric multilayer film. The condensing lens group 104 includes two convex lenses 105 and 106, and condenses the light beam transmitted through the color separation filter 94 on the phosphor element 100G. Here, the condensing lens group 90 includes a biconvex lens 91 and a biconcave lens 92, but instead of the biconvex lens 91 and the biconcave lens 92, a lens having a convex shape or a concave shape only on one side may be used.

  The phosphor element 100G absorbs an incident light beam as excitation light and outputs fluorescent light in a green wavelength region centered at about 550 nm. As described above, the interval between the seven light beams reflected by the light reflecting mirrors 81 to 87 shown in FIG. 2 is narrower than the interval between the seven light beams emitted from the excitation light source group. The condensing lens group 90 further narrows the interval between the light beams reflected by the light reflecting mirrors 81 to 87. Thereby, the cross-sectional diameter of the light beam incident on the phosphor element 100G is reduced, and the light collection efficiency in the phosphor element 100G is improved. For example, the phosphor element 100G can be irradiated with a light beam having a cross-sectional diameter of about 2 mm. Here, a diffusion element may be disposed between the condenser lens group 90 and the color separation filter 94 in order to make the intensity distribution of the light beam condensed on the phosphor element 100G uniform. By disposing the diffusing element, the deviation of the light density of the light flux at the condensing position is reduced and the temperature rise is suppressed, so that the conversion efficiency of the phosphor element 100G is improved.

  The phosphor element 100G is arranged in a fixed state in the present embodiment, but is not limited to this. For example, a green phosphor applied to the periphery of the rotating plate may be used in place of the phosphor element 100G. As a result, the cooling mechanism can be simplified.

  The condensing lens group 104 emits the fluorescent light radiated from the phosphor element 100G substantially in parallel. The fluorescent light transmitted through the condenser lens group 104 is reflected by the color separation filter 94. The fluorescent light reflected by the color separation filter 94 is transmitted through the condensing optical system 95, reflected by the color separation filter 111, and then condensed by the condensing optical system 112 on the incident end face 113 i of the light intensity equalizing element 113. Is done. The color separation filter 111 has an optical characteristic of transmitting incident light in the blue wavelength range and reflecting without transmitting incident light in the green wavelength range and the red wavelength range. For example, the color separation filter 111 can be configured by a dichroic mirror formed of a dielectric multilayer film.

  In addition, although the said condensing lens group 90 has a function which makes an incident light beam substantially parallel, it is not limited to this. The blue laser light may be condensed on the phosphor element 100G by a combination of the condenser lens group 90 and the condenser lens group 104. However, the light beam (fluorescent light) emitted from the phosphor element 100G needs to be condensed on the incident end face 113i of the light intensity uniformizing element 113 by a combination of the condenser lens groups 104, 95, and 112. For this reason, it is preferable in terms of design that the light beams emitted from the condenser lens group 104 toward the color separation filter 94 are substantially parallelized.

  The light intensity uniformizing element 113 is an optical element that uniformizes the light intensity distribution in the cross section of the light beam incident from the incident end face 113i (that is, in a plane orthogonal to the optical axis of the light intensity uniformizing element 113). . Thereby, the illuminance distribution of the light beam incident on the light valve 121 is made uniform. The light propagating inside the light intensity uniformizing element 113 is totally reflected on the inner surface a plurality of times and is superimposed in the vicinity of the emission end face 113o. Thereby, a substantially uniform light intensity distribution can be obtained in the vicinity of the emission end face 113o. Therefore, the emission end face 113o of the light intensity uniformizing element 113 serves as a surface light source that emits light with uniform luminance.

  For example, a polygonal column (rod) made of a transparent optical material such as a glass material or a transparent resin material can be used as the light intensity uniformizing element 113. The side surface of the polygonal column is used as a total reflection surface that causes total internal reflection of light at the interface between the optical material and external air. Alternatively, a hollow pipe (light pipe) having a polygonal cross section having a side surface of the light reflecting mirror can be used as the light intensity uniformizing element 113. A light reflecting film that reflects light to the inside is formed on the side surface of the hollow pipe. FIG. 3 is a perspective view showing an example of the light intensity equalizing element 113. The light intensity uniformizing element 113 shown in FIG. 3 is a quadrangular prism having a Z-axis direction as a longitudinal direction and a rectangular cross section in the XY plane. The side surface is configured as a light reflection mirror or a total reflection surface. In the present embodiment, the light emitting end 113o of the light intensity equalizing element 113 and the light modulation surface of the light valve 121 are in an optically conjugate relationship. For this reason, from the viewpoint of light utilization efficiency, the aspect ratio L: H of the light valve 121 (for example, L: H = 4: 3) and the aspect ratio L0 of the light emitting end face 113o of the light intensity equalizing element 113: It is preferable to match H0 with each other.

  The relay lens group 115 includes a concave / convex lens (meniscus lens) 116, a convex lens 117, and a biconvex lens 118, as shown in FIG. The light beam emitted from the emission end face 113 o of the light intensity uniformizing element 113 is transmitted through the relay lens group 115 and reflected by the bending mirror 120 toward the light valve 121. The bending mirror 120 has a function of bending the optical path of the light beam. The light beam reflected by the bending mirror 120 passes through the condenser lens 122 and enters the light valve 121. The relay lens group 115 is composed of three lenses 116 to 118, but may be composed of two lenses. In this case, it is preferable in design that the distance between the light intensity uniformizing element 113 and the bending mirror 120 is narrowed.

  The various optical members 104, 94, 95, 111, 112, 113, 115, 120, and 122 described above constitute a light guide optical system that guides the fluorescent light emitted from the phosphor element 100 </ b> G to the light valve 121. The

  On the other hand, the red light source 100R is configured by a red LED that emits light in a red wavelength region (peak wavelength: about 620 nm). The red light emitted from the red light source 100R is converted into substantially parallel light by the lens group 101 including the two convex lenses 102 and 103. The red light beam emitted from the lens group 101 passes through the color separation filter 94 and the condensing optical system 95 and is reflected by the color separation filter 111. The red light beam reflected by the color separation filter 111 is condensed on the incident end face 113 i of the light intensity uniformizing element 113 by the condensing optical system 112. The light intensity uniformizing element 113 uniformizes the light intensity distribution in the cross section of the red light beam incident inside from the incident end face 113i, and emits the red light flux having a substantially uniform light intensity distribution from the emission end face 113o. The red light beam emitted from the emission end face 113 o enters the light valve 121 through the relay lens group 115, the bending mirror 120, and the condenser lens 122.

  On the other hand, the blue light source 100B is composed of a blue LED that emits light in a blue wavelength region (peak wavelength: about 460 nm). Blue light emitted from the blue light source 100 </ b> B is converted into substantially parallel light by a lens group 107 including two convex lenses 108 and 109. The blue light beam emitted from the lens group 107 is transmitted through the color separation filter 111 and then condensed on the incident end surface 113 i of the light intensity uniformizing element 113 by the condensing optical system 112. The light intensity uniformizing element 113 equalizes the light intensity distribution in the cross section of the blue light beam incident inside from the incident end face 113i, and emits the blue light flux having a substantially uniform light intensity distribution from the emission end face 113o. The blue light beam emitted from the emission end face 113 o enters the light valve 121 through the relay lens group 115, the bending mirror 120, and the condenser lens 122.

  In addition to the function of controlling the operation of the light valve 121, the control unit 3 has a function of individually controlling the timing at which the excitation light source group, the blue light source 100B, and the red light source 100R emit light according to the image signal VS. . The control unit 3 controls the operation of the light valve 121 in accordance with the respective light emission timings of the excitation light source group, the blue light source 100B, and the red light source 100R.

  In addition, although the red light source 100R and the blue light source 100B are comprised by the LED light source, it is not limited to this, You may comprise by LD (laser diode). In this case, a high luminance red light source and blue light source can be realized by arranging a plurality of LDs in a planar shape (for example, a matrix).

  FIG. 4 is a diagram schematically showing a part of the configuration of the projection display device 1 when viewed from the front side (X-axis negative direction side). In FIG. 4, the components of the excitation light source unit 100E and the condensing lens group 90 are indicated by broken lines for convenience of explanation.

  The light beam reflected by the bending mirror 120 passes through the condenser lens 122 and then enters the light valve 121. As described above, the light valve 121 spatially modulates the incident light beam according to the modulation control signal MC, thereby outputting modulated light representing an optical image. The projection optical system 124 enlarges and projects an optical image represented by the modulated light incident from the light modulation surface (light emission surface) of the light valve 121 onto the projection surface 150 of the external screen.

  As shown in FIG. 4, the light reflecting mirrors 81 to 87 are arranged stepwise, and the height of the light reflecting mirrors 81 to 87 with respect to the excitation light sources 11 to 71 approaches the optical axis OA of the projection optical system 124. It becomes smaller as it goes away from the optical axis OA. Therefore, as shown in FIG. 1 and FIG. 4, an optical path that does not interfere with the light reflecting element 80 can be secured at a position immediately above the end portions (the light reflecting mirrors 86 and 87) of the light reflecting element 80. Therefore, the light valve 121 and the projection optical system 124 are placed at positions overlapping the end portions (light reflecting mirrors 86 and 87) of the light reflecting element 80 in the lateral direction (Z-axis direction) without contacting the light reflecting element 80. It is possible to arrange. Thereby, the projection display apparatus 1 which has a compact lateral width can be provided.

  The conventional projectors disclosed in Patent Documents 1 and 2 each have a projection-side optical system (projection optical system) that projects image light emitted from the DMD onto a screen. In recent years, the flexibility of projector installation has increased as a market requirement, but the projection-side optical system is not arranged at the center in the casing, but at the end in the casing. The projector must be placed at a side biased position. On the other hand, in the projection display device 1 according to the present embodiment, the projection optical system 124 can be disposed at a position closer to the center of the housing 2 than a conventional projector. Therefore, the installation position of the projection display device 1 with respect to the external screen can be determined flexibly as compared with the conventional projector.

  Further, since the light valve 121 is disposed at a position overlapping with the end portions (light reflecting mirrors 86 and 87) of the light reflecting element 80 in the lateral direction, the light valve is changed from the light intensity equalizing element 113 to the light valve. The optical path length up to 121 can be shortened. As a result, the degree of freedom in design is increased and the light utilization efficiency is improved.

  Furthermore, in the present embodiment, as shown in FIG. 4, the optical axis OA of the projection optical system 124 is in the height direction (Y) with respect to the central axis CA of the light exit surface (light modulation surface) of the light valve 121. Shifted by a distance δ in the positive axis direction). Thereby, a sufficient distance is ensured between the optical path of the modulated light from the light valve 121 toward the projection optical system 124 and the light reflecting element 80 (light reflecting mirrors 85, 86, 87). A sufficient distance from the light reflecting element 80 (light reflecting mirrors 85, 86, 87) is also ensured. Therefore, it is possible to reliably prevent the optical path from the bending mirror 120 to the light valve 121 from interfering with the light reflecting element 80. Therefore, the projection display device 1 can be efficiently downsized.

  If the light reflecting element 80, the condensing lens 122, the light valve 121, the projection optical system 124, and the optical path formed by these elements do not interfere with each other, the light reflecting element 80, the condensing lens 122, the light valve 121, and the projection optical system. The arrangement of the system 124 is not particularly limited. For example, the projection display device 1 can be further downsized by further shifting the positions of the light reflecting mirrors 81 to 87 in the positive direction of the Z-axis.

Embodiment 2. FIG.
Next, a second embodiment according to the present invention will be described. FIG. 5 is a diagram schematically showing the main configuration of the projection display apparatus 1B of the second embodiment. As shown in FIG. 5, the projection display apparatus 1B includes a housing 2B that forms an outer frame. Inside the housing 2B, a control unit 3, an excitation light source unit 100E, and a condensing lens group 90 are provided. , Phosphor element 100G, red light source 100R, blue light source 100B, lens groups 101, 104, 107, color separation filters 94, 111, condensing optical systems 95, 112, light intensity equalizing element 113, relay lens group 115, bending A mirror 131, a concave mirror 132, a light valve 121, and a projection optical system 124B are provided.

  The X-axis direction, Y-axis direction, and Z-axis direction in FIG. 5 are orthogonal to each other. Here, the X-axis direction is parallel to the optical axis OA of the projection optical system 124B, the Y-axis direction is parallel to the height direction of the projection display apparatus 1B, and the Z-axis direction is the projection display apparatus 1B. It is parallel to the horizontal width direction.

  The configuration of the projection display apparatus 1B according to the present embodiment is that the first embodiment has the bending mirror 131 and the concave mirror 132 as light guide members that guide the light beam emitted from the relay lens group 115 to the light valve 121. This is different from the configuration of the projection display device 1.

  Further, the light valve 121 of the present embodiment is arranged at a position different from that of the light valve 121 (FIG. 1) of the first embodiment. The projection optical system 124B refracts the modulated light emitted from the light valve 121 and emits projection light (image light) from the front surface 124Bf. The projection optical system 124B can enlarge and project the optical image represented by the modulated light onto the projection surface of the external screen.

  FIG. 6 is a diagram schematically showing the arrangement of the bending mirror 131 and the concave mirror 132 of the present embodiment. The bending mirror 131 has a function of bending the optical path of the light beam. The light beam reflected by the bending mirror 131 is reflected by the concave surface 132 c of the concave mirror 132 and enters the light modulation surface of the light valve 121. The light valve 121 outputs modulated light representing an optical image by spatially modulating the incident light beam according to the modulation control signal MC.

  As in the case of the first embodiment, the light valve 121 and the projection optical system 124B are arranged at positions overlapping with the end portions (the light reflecting mirrors 86 and 87) of the light reflecting element 80 in the lateral direction. In the present embodiment, since the light valve 121 is disposed at a position immediately above the light reflecting mirrors 86 and 87, the position of the light valve 121 is positioned in the optical axis direction of the projection optical system 124B. Overlapping position 87.

  As described above, in the second embodiment, the light reflection element 80 is not brought into contact with the end portion (light reflection mirrors 86 and 87) of the light reflection element 80 and overlapped in the lateral direction (Z-axis direction). It is possible to arrange the light valve 121 and the projection optical system 124B. Further, the light valve 121 can be disposed at a position immediately above the end of the light reflecting element 80. Therefore, it is possible to provide a projection display device 1B having a compact lateral width.

  In the present embodiment, as shown in FIG. 5, the light valve 121 is disposed immediately above the light reflecting mirrors 86 and 87, and the projection optical system 124B is on the X axis negative direction side of the light reflecting mirrors 86 and 87. It is arranged at a position shifted to. For this reason, the projection optical system 124B emits projection light in the negative X-axis direction. Instead of such a configuration, the arrangement of the bending mirror 131, the concave mirror 132, the light valve 121, and the projection optical system 124B may be changed so that the projection light is emitted in the positive direction of the X axis. FIG. 7 is a diagram schematically showing a main configuration of a projection display apparatus 1Ba, which is a modification of the second embodiment. The projection display apparatus 1Ba is configured to emit projection light in the positive direction of the X axis.

  The configuration of the projection display device 1Ba shown in FIG. 7 is the same as that of the second embodiment except for the arrangement of the bending mirror 131, the concave mirror 132, the light valve 121 and the projection optical system 124B and the outer shape of the housing 2Ba. The configuration is the same as that of the projection display device 1B. In the projection display apparatus 1Ba, the light valve 121 is disposed at a position shifted to the X axis negative direction side from the light reflecting mirrors 86 and 87, and the projection optical system 124B is disposed immediately above the light reflecting mirrors 86 and 87. Has been. The bending mirror 131 reflects the light beam emitted from the relay lens group 115 toward the concave mirror 132. The light beam reflected by the concave surface 132 c of the concave mirror 132 enters the light modulation surface of the light valve 121. The projection optical system 124B refracts the modulated light emitted from the light valve 121 to emit the projection light in the positive direction of the X axis, and enlarges and projects the optical image represented by the modulated light on the projection surface 150. Can do. With such a configuration, it is possible to provide a compact projection display device 1Ba having a small size in the X-axis direction.

Embodiment 3 FIG.
Next, a third embodiment according to the present invention will be described. FIG. 8 is a diagram schematically showing the main configuration of the projection display apparatus 1C according to the third embodiment. The configuration of the projection display device 1C of the present embodiment is the same as the configuration of the projection display device 1 of the first embodiment except for the excitation light source unit 100EC, the condenser lens group 90C, and the housing 2C. . FIG. 9 is a diagram showing a schematic configuration of the excitation light source unit 100EC and the condensing lens group 90C when viewed from the front side (X-axis negative direction side) of the projection display apparatus 1C.

  The excitation light source unit 100EC has the same excitation light source group as the excitation light source group of the first embodiment, the same collimating lens group as the collimating lens group of the first embodiment, and a single light reflecting surface. And a plate-like light reflecting element 88. As shown in FIG. 9, the light reflecting surface of the light reflecting element 88 is opposed to the light emitting end of the excitation light source group, and the light beam incident at an incident angle of about 45 ° is laterally (Z-axis negative direction). The light is reflected and emitted toward the condenser lens group 90C. Therefore, the light reflecting element 88 bends the optical path of the light beam by about 90 °. The light reflecting surface of the light reflecting element 88 is preferably formed of a silver coating layer in order to efficiently reflect blue light.

  The condensing lens group 90C includes a biconvex lens 91C and a biconcave lens 92C. The condensing lens group 90C condenses the light beam incident from the light reflecting element 88 and reduces the cross-sectional diameter (dimensions in the X-axis direction and the Y-axis direction) of the light beam. After that, it is converted again into a substantially parallel light beam. The light beam emitted from the condensing lens group 90C passes through the color separation filter 94 and the condensing lens group 104, and then enters the phosphor element 100G. Here, the condensing lens group 90C includes a biconvex lens 91C and a biconcave lens 92C. Instead of the biconvex lens 91C and the biconcave lens 92C, a lens having a convex shape or a concave shape only on one side may be used.

  FIG. 10 is a diagram schematically showing a part of the configuration of the projection display apparatus 1 </ b> C when viewed from the front side (X-axis negative direction side). In FIG. 10, the components of the excitation light source unit 100EC and the condenser lens group 90C are indicated by broken lines for convenience of explanation.

  As shown in FIG. 10, the height of the light reflecting surface of the light reflecting element 88 from the excitation light source group decreases as it approaches the optical axis OA of the projection optical system 124, and moves away from the optical axis OA of the projection optical system 124. It gets bigger. Therefore, as shown in FIGS. 8 and 10, an optical path that does not interfere with the light reflecting element 88 can be secured at a position immediately above the right end of the light reflecting element 88. Therefore, it is possible to arrange the light valve 121 and the projection optical system 124 at a position overlapping the end of the light reflecting element 88 in the lateral direction (Z-axis direction) without making contact with the light reflecting element 88. Thereby, the projection display apparatus 1C having a compact lateral width can be provided.

  As in the first embodiment, the optical path length from the light intensity uniformizing element 113 to the light valve 121 can be shortened. As a result, the degree of freedom in design is increased and the light utilization efficiency is improved.

  The light reflecting element 88 according to the present embodiment does not have a function of reducing the interval between the plurality of light beams emitted from the excitation light source group unlike the light reflecting element 80 according to the first embodiment. As compared with the condenser lens group 90, the condenser lens group 90C has a large aperture. Therefore, in order to reduce the aperture of the condensing lens group 90C, the number of excitation light sources may be reduced and, for example, an excitation light source group arranged in about 3 rows and 3 columns may be used.

Embodiment 4 FIG.
Next, a fourth embodiment according to the present invention will be described. FIG. 11 is a diagram schematically showing the main configuration of the projection display apparatus 1D of the fourth embodiment. The configuration of the projection display device 1D according to the present embodiment is the same as the configuration of the projection display device 1 according to the first embodiment except for the excitation light source unit 100ED, the condensing lens group 90D, and the housing 2D. .

  12 is a diagram showing a schematic configuration of the excitation light source unit 100ED when viewed from the bottom surface side (Y-axis negative direction side) of the projection display device 1D, and FIG. It is a figure which shows schematic structure of excitation light source unit 100ED and the condensing lens group 90D when it sees from the X-axis negative direction side.

  The excitation light source unit 100ED includes the excitation light sources having the same configuration as the excitation light sources 11 to 13, 21 to 23, 31 to 33, 41 to 43, 51 to 53, 61 to 63, and 71 to 73 of the first embodiment, and the above. The collimating lenses 15 to 17, 25 to 27, 35 to 37, 45 to 47, 55 to 57, 65 to 67, and 75 to 77 of the first embodiment are included. However, the optical axes of the excitation light sources 11 to 73 and the collimating lenses 15 to 77 are set so as to be inclined rather than 90 ° with respect to the optical axes of the condenser lens group 90D, as shown in FIG. ing. Here, the angle formed by the optical axes of the excitation light sources 11 to 73 and the collimating lenses 15 to 77 and the optical axis of the condenser lens group 90D is larger than 90 °.

  The excitation light source unit 100ED includes a plate-like light reflecting element 89 having a single light reflecting surface. The light reflecting surface of the light reflecting element 89 is opposed to the light emitting end of the excitation light source group, reflects a light beam incident at an incident angle θ exceeding 45 ° in the lateral direction (Z-axis negative direction), and a condenser lens group. It emits toward 90D. The light reflecting surface of the light reflecting element 89 is preferably formed of a silver coating layer in order to efficiently reflect blue light.

  The condensing lens group 90D is composed of a biconvex lens 91D and a biconcave lens 92D. The condensing lens group 90D condenses the light beam incident from the light reflecting element 89 and reduces the cross-sectional diameter (dimensions in the X-axis direction and Y-axis direction) of the light beam. Then, it is converted again into a substantially parallel light beam. The light beam emitted from the condensing lens group 90D passes through the color separation filter 94 and the condensing lens group 104 and then enters the phosphor element 100G. Here, the condensing lens group 90D includes a biconvex lens 91D and a biconcave lens 92D, but instead of the biconvex lens 91D and the biconcave lens 92D, a lens having a convex shape or a concave shape on only one side may be used.

  FIG. 14 is a diagram schematically showing a part of the configuration of the projection display device 1D when viewed from the front side (X-axis negative direction side). In FIG. 14, the components of the excitation light source unit 100ED and the condensing lens group 90D are shown by broken lines for convenience of explanation.

  As shown in FIG. 14, the height of the light reflecting surface of the light reflecting element 89 from the excitation light source group decreases as it approaches the optical axis OA of the projection optical system 124, and moves away from the optical axis OA of the projection optical system 124. It gets bigger. For this reason, as shown in FIGS. 11 and 14, an optical path that does not interfere with the light reflecting element 89 can be secured at a position immediately above the right end of the light reflecting element 89. Therefore, it is possible to arrange the light valve 121 and the projection optical system 124 at a position overlapping the end of the light reflecting element 89 in the lateral direction (Z-axis direction) without making contact with the light reflecting element 89. Thereby, the projection display device 1D having a compact lateral width can be provided. As in the first embodiment, the optical path length from the light intensity uniformizing element 113 to the light valve 121 can be shortened. As a result, the degree of freedom in design is increased and the light utilization efficiency is improved.

  In the present embodiment, since the optical axes of the excitation light sources 11 to 73 are set obliquely, an increase in the diameter of the condensing lens group 90D can be suppressed. Therefore, it is possible to provide a projection display device 1D that is reduced in size in the horizontal direction (Z-axis direction) without increasing the size in the height direction (Y-axis positive direction).

  Furthermore, since the light reflecting element 89 of the present embodiment has a single light reflecting surface, compared to the case of the first embodiment, the installation tolerance of the excitation light source group and the collimating lens group (the error of the installation position). There is an advantage that the allowable range can be slightly increased. Since the light reflecting element 80 of the first embodiment is composed of a plurality of light reflecting mirrors 81 to 87 separated from each other as shown in FIG. 2, in order to ensure high light utilization efficiency, the plurality of light reflecting elements are reflected. The excitation light source group and the collimating lens group must be accurately arranged at positions corresponding to the light reflecting surfaces of the mirrors 81 to 87. Therefore, in the first embodiment, it is desirable to reduce the installation tolerance of the excitation light source group and the collimating lens group. On the other hand, since the light reflecting surface of the light reflecting element 89 of the present embodiment is composed of one sheet, the installation tolerance of the excitation light source group and the collimating lens group can be made relatively large.

  In this embodiment, the bending mirror 120 and the condensing lens 122 are used as a light guide member for guiding the light beam emitted from the relay lens group 115 to the light valve 121. Instead, the above-described embodiment is used. The bending mirror 131 and the concave mirror 132 of the form 2 may be used.

Embodiment 5 FIG.
Next, a fifth embodiment according to the present invention will be described. FIG. 15 is a diagram schematically showing a main configuration of a projection display apparatus 1E according to the fifth embodiment. As shown in FIG. 15, the projection display apparatus 1E includes a housing 2E that constitutes an outer frame. Inside the housing 2E, a control unit 3, an excitation light source unit 100ED, and a condensing lens group 90D. , Phosphor element 100G, red light source 100R, blue light source 100B, lens groups 101, 104, 107, color separation filters 94, 111, condensing optical systems 95, 112, light intensity equalizing element 113, relay lens group 115, internal A total reflection prism 140, a light valve 121, and a projection optical system 124E are provided.

  The X-axis direction, Y-axis direction, and Z-axis direction in FIG. 15 are orthogonal to each other. Here, the X-axis direction is parallel to the optical axis of the lens group 101, the Y-axis direction is parallel to the height direction of the projection display device 1E, and the Z-axis direction is the optical axis of the lens group 104. Parallel.

  The projection display apparatus 1E of the present embodiment includes the same excitation light source unit and condenser lens group as the excitation light source unit 100ED and condenser lens group 90D of the fourth embodiment. In addition, the configuration of the projection display device 1E includes the internal total reflection prism 140 as a light guide member that guides the light beam emitted from the relay lens group 115 to the light valve 121, and thus the projection display device according to the fourth embodiment. It is different from the 1D configuration. Furthermore, the light valve 121 of the present embodiment is arranged at a position different from that of the light valve 121 (FIG. 11) of the fourth embodiment.

  The internal total reflection prism 140 is configured by joining two triangular prisms 141 and 142 to each other via an air layer. As shown in FIG. 15, the light beam incident on the inside of the triangular prism 141 from the relay lens group 115 is totally reflected by the triangular prism 141 and emitted toward the light valve 121. The modulated light that has entered the triangular prism 141 from the light valve 121 passes through the triangular prisms 141 and 142 and then enters the projection optical system 124E. The projection optical system 124E refracts the modulated light emitted from the light valve 121 and emits projection light (image light) from the front surface 124Ef. The projection optical system 124E can enlarge and project the optical image represented by the modulated light onto the projection surface of the external screen.

  FIG. 16 is a diagram schematically showing a part of the configuration of the projection display apparatus 1E when viewed from the front side (X-axis negative direction side). In FIG. 16, the components of the excitation light source unit 100ED and the condensing lens group 90D are indicated by broken lines for convenience of explanation.

  As in the case of the fourth embodiment, the light valve 121 and the projection optical system 124E are arranged at positions overlapping the end of the light reflecting element 89 in the lateral direction (Z-axis direction). In the present embodiment, since the light valve 121 is disposed at a position immediately above the end of the light reflecting element 89, the position of the light valve 121 is the light reflecting element 89 in the optical axis direction of the projection optical system 124E. Overlapping with the position of the end of Therefore, it is possible to provide a projection display device 1E having a compact lateral width.

  The height of the central axis CA of the light valve 121 is the same as the height of each optical axis of the relay lens group 115 and the internal total reflection prism 140. Therefore, it is possible to provide a projection display device 1E having a small dimension in the height direction (Y-axis positive direction).

  In the first to fourth embodiments, the optical axis OA of the projection optical systems 124 and 124B is shifted in the height direction by a predetermined amount δ with respect to the central axis CA of the light valve 121. On the other hand, even in the configuration using the internal total reflection prism 140 of the present embodiment, the optical axis OA of the projection optical system 124E is shifted by δ with respect to the central axis of the light valve 121, as shown in FIG. However, even if the principal ray incident on the projection optical system 124E is substantially parallel to the optical axis OA and the shift amount δ is zero, it is possible to avoid the light reflecting element 89 from interfering with the optical path. .

Modified examples of the first to fifth embodiments.
Although various embodiments according to the present invention have been described above with reference to the drawings, these are examples of the present invention, and various forms other than the above can be adopted. For example, in the first to fifth embodiments, an LD is used as the excitation light source group and an LED or LD is used as the red light source 100R and the blue light source 100B. However, the present invention is not limited to these. You may use semiconductor light emitting elements other than these LD and LED.

  The excitation light source group described above emits light in the blue wavelength region in accordance with the phosphor material of the phosphor element 100G, but is not limited thereto. The phosphor material of the phosphor element 100G may be changed to another phosphor material, and the emission wavelength range of the excitation light source group may be appropriately selected according to this change. Further, instead of the phosphor element 100G and the red light source 100R, a green phosphor and a red phosphor applied to a divided region of the peripheral portion of the rotating plate may be used. Thereby, simplification of an apparatus structure is realizable.

  In addition, the projection display devices 1, 1B, 1C, 1D, and 1E of Embodiments 1 to 5 are all pumping light sources 11 to 13, 21 to 23, 31 to 33, arranged in 3 rows and 7 columns. Although it has 41-43, 51-53, 61-63, 71-73, it is not limited to this arrangement | sequence. The arrangement of the excitation light sources is not limited to 3 rows and 7 columns, and may be 4 rows and 9 columns, for example.

  Further, the arrangement of the red light source 100R, the blue light source 100B, and the phosphor element 100G is not limited to the arrangement in the first to fifth embodiments. For example, the projection display devices 1 and 1B to 1D may be configured by changing the arrangement positions of the red light source 100R, the blue light source 100B, and the phosphor element 100G.

  In addition, the projection display devices 1, 1B, 1C, 1D, and 1E of the first to fifth embodiments all include the reflective light valve 121, but the present invention is not limited to this. A transmissive light valve is employed instead of the reflective light valve 121, and the configurations of the projection display devices 1, 1B, 1C, 1D, and 1E of the first to fifth embodiments are appropriately changed accordingly. Also good.

  1, 1B, 1Ba, 1C, 1D, 1E Projection display device, 2, 2B, 2Ba, 2C, 2D, 2E housing, 3 control unit, 11-13, 21-23, 31-33, 41-43, 51-53, 61-63, 71-73 Excitation light source, 15-17, 25-27, 35-37, 45-47, 55-57, 65-67, 75-77 Parallelizing lens, 80, 88, 89 Light reflecting element, 81-87 Light reflecting mirror, 90, 90C, 90D Condensing lens group, 94, 111 Color separation filter, 95, 112 Condensing optical system, 100R red light source, 100B blue light source, 100G phosphor element, 100E , 100EC, 100ED excitation light source unit, 113 light intensity uniformizing element, 115 relay lens group, 120, 131 folding mirror, 121 light valve 124, 124B, 124E projection optical system, 132 concave mirror, 140 internal total reflection prism, 150 projection surface.

Claims (14)

A light valve that spatially modulates the incident beam to generate modulated light;
A projection optical system for enlarging and projecting an optical image represented by the modulated light onto an external projection surface;
An excitation light source group consisting of a plurality of light sources arranged along a lateral direction intersecting the optical axis direction of the projection optical system;
A light reflecting element having a single or a plurality of light reflecting surfaces facing the light emitting ends of the plurality of light sources;
A phosphor element that absorbs and emits light reflected by the light reflecting surface as excitation light; and
A light guide optical system that guides the fluorescent light emitted from the phosphor element to the light valve;
The light reflecting surface of the light reflecting element reflects a plurality of light beams emitted from the plurality of light sources in the lateral direction and in a direction away from the optical axis of the projection optical system,
The height of the light reflecting surface from the excitation light source group decreases as it approaches the optical axis of the projection optical system,
The light valve is disposed at a position higher than the optical axis side end of the projection optical system in the light reflecting element, and is disposed at a position overlapping with the light reflecting element in the lateral direction. A projection display device characterized. The projection display device according to claim 1,
The light valve has a light emitting surface for emitting the modulated light,
The optical axis of the projection optical system is shifted in the height direction from the central axis of the light exit surface,
The projection display device, wherein the excitation light source group emits light in the height direction.   3. The projection display device according to claim 1, wherein the projection optical system is disposed at a position higher than the end of the light reflecting element and overlaps the end in the lateral direction. A projection display device characterized by being arranged at a position.   4. The projection display device according to claim 3, wherein the projection optical system is disposed at a position overlapping with the end of the light reflecting element in an optical axis direction of the projection optical system. Projection display device.   4. The projection display device according to claim 1, wherein the light valve overlaps with the end of the light reflecting element in an optical axis direction of the projection optical system. 5. A projection display device characterized by being arranged.   5. The projection display device according to claim 1, wherein the plurality of light sources are arranged in a plane and regularly. 6. A projection display device according to any one of claims 1 to 6,
The light reflecting element includes a plurality of light reflecting mirrors each having the plurality of light reflecting surfaces,
The projection display device, wherein the plurality of light reflecting mirrors are arranged stepwise.   The projection display device according to claim 1, wherein the light reflecting element has the single light reflecting surface.   9. The projection display device according to claim 8, wherein the optical axes of the plurality of light sources are set such that light beams emitted from the plurality of light sources are incident on the light reflecting surface at an incident angle of approximately 45 °. Projection type display device.   9. The projection display device according to claim 8, wherein the optical axes of the plurality of light sources are set so that light beams emitted from the plurality of light sources are incident on the light reflecting surface at an incident angle exceeding 45 degrees. Projection type display device. A projection display device according to any one of claims 1 to 10,
A collimating lens for collimating the light beams emitted from the plurality of light sources,
The projection display device, wherein the light reflecting surface of the light reflecting element reflects a collimated light beam incident from the collimating lens. A projection display device according to any one of claims 1 to 11,
The light guide optical system is:
A light intensity uniformizing element for uniformizing the intensity distribution of the fluorescent light emitted from the phosphor element;
A projection display apparatus comprising: a relay optical system that guides a light beam emitted from the light intensity uniformizing element to the light valve.   13. The projection display device according to claim 1, wherein each of the plurality of light sources includes a first semiconductor light emitting element that emits light in a first wavelength region. Projection display device. The projection display device according to claim 13,
A second semiconductor light emitting element that emits light in a second wavelength range of a color different from the emission color of the phosphor element;
A third semiconductor light emitting element that emits light in a third wavelength range of a color different from both the emission color of the phosphor element and the emission color of the second semiconductor light emitting element;
The light guide optical system guides a light beam emitted from the second semiconductor light emitting element and the third semiconductor light emitting element to the light valve.

Images