JP5199697B2 - Illumination device and projection display device - Google Patents

Description

  The present invention relates to an illuminating device and a projection display apparatus using the illuminating device, and is particularly suitable for use when generating illumination light using a plurality of laser light sources.

  2. Description of the Related Art Conventionally, projection video display devices (hereinafter referred to as “projectors”) that enlarge and project light modulated by a video signal onto a screen have been commercialized and widely spread. This type of projector is equipped with an illuminating device for supplying illuminating light to a light modulation element such as a liquid crystal panel, and the light source of such an illuminating device has so far been an ultra-high pressure mercury lamp, a metal halide lamp, a xenon lamp, etc. The lamp light source was used.

  However, in recent years, a projector using a solid light source such as a semiconductor laser instead of a lamp light source has been developed. Laser light sources are excellent in ability to express a wide color space with high brightness and high definition, and are attracting attention as light sources for next-generation projectors.

When projecting an image on a large screen using such a projector, it is necessary to increase the brightness of the illumination light. Here, as a method of increasing the luminance of illumination light, there is a method of using laser beams emitted from a plurality of laser light sources by combining them. For example, in Patent Document 1 below, the intensity of illumination light is increased by combining light beams of laser beams emitted from a plurality of laser light sources using a prism mirror.
JP 2006-337923 A

  In general, since the laser light emitted from the laser light source has a certain spread angle, the beam shape of the laser light increases as the laser light propagates. For this reason, if the optical path length to the plane perpendicular to the traveling direction of the combined light beam is different between the laser light sources as in Patent Document 1, the beam shape on the plane becomes non-uniform. In an optical system that uses a lens to make light uniform, the beam shape of each laser beam when entering the fly-eye lens becomes non-uniform, resulting in a problem that the light-homogenizing effect of the fly-eye lens is reduced. .

  FIG. 11 is a diagram schematically illustrating an example of a beam shape of laser light when entering the fly-eye lens. If the beam shape when entering the fly-eye lens is different between the beams as shown in FIG. 5B, the fly-eye lens is more effective than the case where the beam shape is uniform as shown in FIG. The ratio of the laser beam incident area to the area decreases. For this reason, in the case of the same figure (b), the light equalization effect by a fly eye lens will fall rather than the case of the same figure (a).

  Here, in order to increase the uniformity effect of the fly-eye lens, the distance between the illumination device and the fly-eye lens is adjusted, and the smaller beam shape in FIG. It can be extended to run on. However, in this case, the larger beam shape is expanded in the same way, so that the larger beam shape protrudes from the effective area of the fly-eye lens, and this protruding portion of the laser light enters the light modulation element such as a liquid crystal panel. It will not be guided. For this reason, in this case, the use efficiency of the illumination light is reduced as compared with the case of FIG. 5B, and the luminance of the illumination light on the light modulation element is reduced accordingly. As a result, there arises a problem that the luminance of the image light on the screen is lowered.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide an illuminating device capable of simultaneously enhancing the effect of uniforming illumination light and the efficiency of using illumination light, and a projector using the same. To do.

The illumination device according to the first aspect of the present invention includes a first light source group that emits light in a first direction, a second light source group that emits light in a second direction, and the first light source. And a reflecting means for making the traveling direction of the light emitted from the group and the second light source group coincide with the third direction and to enter the fly-eye lens, the first light source group includes the first direction. The second light source group is disposed in a common plane perpendicular to the second direction, and the light emission position of the first light source group and the second light source group are disposed in a common plane perpendicular to the second direction . The light emitting position of the light source group is disposed so as to face each other, and the reflecting means has a shape whose cross section is a right-angled isosceles triangle, and the first light source group and the second light source group And further converging the light emitted from the first light source group, and The cylindrical lens for converging the light emitted from the light source group respectively arranged in the beam shape of the first light source group and each light incident from the second light source group in the fly-eye lens is uniform In addition, the first light source group and the second light source group so that light enters the fly eye lens from the first light source group and the second light source group without leaving an effective area of the fly eye lens. The reflection means is arranged.

  In this aspect, each light source constituting the first light source group and the second light source group is constituted by a semiconductor laser array in which a plurality of laser elements are arranged in an array on one semiconductor substrate. Can do.

According to a second aspect of the present invention, in the illumination device according to the first aspect, each of the first light source group and the second light source group includes a common cooling unit.

Projection display device according to the third aspect of the present invention is modulated based an illumination device according to any one of the first to third embodiments, the light passed through the pre-Symbol fly-eye lens to a video signal It has a light modulation element and a projection lens which projects the light modulated by the light modulation element.

According to the illumination device according to the first to second aspects, the optical path length of each light from the first light source group and the second light source group to the plane perpendicular to the light traveling in the third direction is constant. Therefore, when this illumination device is applied to an optical system using the fly-eye lens, the beam shape of each light when entering the fly-eye lens becomes uniform, and for example, as shown in FIG. As described above, each light can be incident on the fly-eye lens without leaving an effective area of the fly-eye lens. Therefore, according to the illuminating device which concerns on this aspect, the light equalization effect by a fly eye lens can be exhibited appropriately, without reducing the utilization efficiency of illumination light.

According to the projection display apparatus according to the third aspect of the present invention, since the illumination apparatus according to the first to third aspects is used, the fly-eye lens is used without reducing the efficiency of use of illumination light. The effect of uniformizing the light can be properly exhibited. Therefore, it is possible to realize high brightness of the image light projected on the screen.

The effects and significance of the present invention will become more apparent from the following description of embodiments. However, the following embodiment is merely an example when the present invention is implemented, and the meaning of the term of the present invention or each constituent element is the same as that described in the following embodiment. It is not limited.

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

  First, FIG. 1 shows a configuration of a light source unit according to the embodiment. As shown, the light source unit includes a semiconductor laser array 11, a copper plate 12, and a liquid cooling jacket 13. In the figure, for the sake of convenience, the light source unit is shown with the front upper portion of the semiconductor laser array 11 cut away so that the laser element 11b can be seen from the outside.

  The semiconductor laser array 11 has a plurality of semiconductor laser elements 11b formed in a semiconductor layer. A conductive plate (copper plate or the like) 11c serving as a cathode is disposed on the top surface of the semiconductor layer, and the cathode (top surface) of each semiconductor laser element 11b is connected to the conductive plate 11c by wire bonding. The bottom surface of the semiconductor layer is an anode of each semiconductor laser element 11b and is in contact with the conductive substrate 11a.

  A hole reaching the substrate 11a is formed in the conductive plate 11c, and a conductive screw 11d is screwed into the substrate 11a through this hole. Therefore, the screw 11d is electrically connected to the anode of the semiconductor laser element 11b. Here, an insulating member 11e is interposed between the screw 11d and the hole. A positive potential is supplied to each semiconductor laser element 11b via a screw 11d, and a negative potential is supplied via a conductive plate 11c. Note that a positive potential may be supplied from the substrate 11a or the screw 11f.

  The substrate 11a is larger in size than the semiconductor layer in order to increase the heat conduction to the liquid cooling jacket 13. The substrate 11a is screwed to the liquid cooling jacket 13 via a screw 11f in a region outside the semiconductor layer arrangement region.

  Here, a copper plate 12 is interposed between the substrate 11 a and the liquid cooling jacket 13 in order to increase the cooling efficiency of the semiconductor laser array 11. The cooling liquid circulates in the liquid cooling jacket 13 through the inlet 13a and the outlet 13b of the liquid cooling jacket 13, thereby removing the heat conducted from the semiconductor laser array 11 to the liquid cooling jacket through the copper plate 12.

  Here, the copper plate 12 is used for thermal diffusion. However, depending on the heat generation area of the semiconductor laser array 11 and the area of the liquid cooling jacket 13, there is a possibility that the cooling efficiency may be improved without using the copper plate 12. is there. In such a case, the copper plate 12 may be omitted. Further, when it is necessary to further increase the cooling capacity, such as when it is necessary to keep the semiconductor laser array 11 at room temperature or lower, a heat transfer element such as a Peltier element is further interposed between the copper plate 12 and the liquid cooling jacket 13. Alternatively, a Peltier element may be arranged in place of the copper plate 12, and the semiconductor laser array 11 may be mounted directly on the Peltier element.

  The entire semiconductor laser array 11 shown in FIG. 1 corresponds to one light source constituting the first and second light source groups of the present invention. That is, the mass of the plurality of semiconductor laser elements 11b arranged in one semiconductor laser array 11 corresponds to one light source constituting the first and second light source groups of the present invention. In other words, one light source in the present invention does not necessarily have to be an independent light source, but is an aggregate of light sources in which a plurality of light sources are densely arranged like the semiconductor laser array 11 in FIG. There may be. In this case, a set of light emitted from each light emitting source becomes light emitted from one light source. The beam shape of such a set of light increases as the light travels.

  In the case where the aggregate of light emitting sources is used as one light source in this way, strictly speaking, there may be an optical path length for each light emitting source. The optical path length of the light emitted from the source is defined as the optical path length of the light source. Therefore, in the configuration of FIG. 1, the optical path length of the laser light emitted from the central semiconductor laser element 11 b among the semiconductor laser elements 11 b arranged in a row is the optical path length of the semiconductor laser array 11. For example, when 24 semiconductor laser elements 11b are arranged in the semiconductor laser array 11, the optical path length of the laser light emitted from the 12th or 13th semiconductor laser element 11b from the end is the optical path length of the semiconductor laser array 11. It is.

  In the following description, the optical axis of the laser light emitted from the central semiconductor laser element 11b among the semiconductor laser elements 11b arranged in a row is used as the optical axis of the semiconductor laser array 11.

  FIG. 2 is a diagram illustrating an optical system of the illumination device according to the embodiment. FIG. 4A is a top view of the lighting device, and FIG. 4B is a front view of the lighting device.

  As illustrated, the optical system of the illumination device includes four light source units 101 to 104 and a prism mirror 201. The light source units 101 to 104 each have the configuration shown in FIG. 1, and the semiconductor laser array 11 having the same optical characteristics (laser wavelength, divergence angle, etc.) is disposed in the light source units 101 to 104. .

  Among these, the light source units 101 and 102 emit laser light in the same direction (first direction) parallel to the X axis in the figure, and the light emission position of the laser light is common to the first direction. It arrange | positions so that it may be located on a plane. The light source units 103 and 104 emit laser light in a second direction opposite to the first direction, and the emission position of the laser light is located on a common plane perpendicular to the second direction. Arranged to do. Further, the light source units 101 and 103 are disposed so that the light emission positions of the laser beams are opposed to each other, and the light source units 102 and 104 are disposed so that the light emission positions of the laser lights are opposed to each other.

  The prism mirror 201 has a shape whose cross section is a right-angled isosceles triangle, and two surfaces sandwiching a right-angled apex angle are mirror surfaces 201a and 201b. The prism mirror 201 is arranged so that the optical axes of the laser beams L01 to L04 emitted from the light source units 101 to 104 are 45 ° with respect to the mirror surfaces 201a and 201b, respectively. That is, the angle α obtained by dividing the apex angle of the prism mirror 201 in the YZ plane in FIG. Therefore, these laser beams L01 to L04 are reflected by the mirror surfaces 201a and 201b and travel in the third direction (Z-axis direction in the figure).

  Furthermore, the light source units 101 to 104 and the prism mirror 201 are arranged so that the optical path lengths from the light source units 101 to 104 to the plane P perpendicular to the third direction are the same. That is, when the dimensions of each part are set as shown in FIG. 5A, A1 = A2, B1 = B2, C1 = C2, A1 = B1 + C1, and A2 = B2 + C2. Here, A1 and A2 are optical path lengths from the light source units 101 and 103 to the reflecting surfaces 201a and 201b, respectively, B1 and B2 are optical path lengths from the light source units 102 and 104 to the reflecting surfaces 201a and 201b, respectively, and C1 is A distance C2 between the light emitting points of the light source units 101 and 102 is a distance between the light emitting points of the light source units 103 and 104.

  FIG. 3A is a diagram schematically showing the arrangement state of the light source units 101 and 102 and the emission state of the laser beams L01 and L02.

  As described above, the light source units 101 and 102 emit laser beams from the respective semiconductor laser elements 11b in the semiconductor laser array 11, and these sets become laser beams L01 and L02. Since the laser beams L01 and L02 have the same divergence angle, the beam shapes of the laser beams L01 and L02 increase as the laser beams L01 and L02 propagate.

  These light source units 101 and 102 are individually held by holding mechanisms 301 and 302. The holding mechanisms 301 and 302 have a mechanism capable of adjusting the positions of the support portions that support the light source units 101 and 102 in the X, Y, and Z directions in the drawing. By adjusting this mechanism, the light emission positions of the light source units 101 and 102 are adjusted in the X, Y, and Z directions in the figure.

  In FIG. 6A, the light source units 101 and 102 are individually held by the holding mechanisms 301 and 302. However, as shown in FIG. The holding mechanism 303 may be used. In this case, the holding mechanisms 301 and 302 have a mechanism capable of adjusting the positions of the light source units 101 and 102 in the X and Y directions in the drawing.

  In addition, in the configuration of FIG. 5B, a common copper plate 12 and liquid cooling jacket 13 are arranged as cooling means for the light source units 101 and 102. That is, both the light source units 101 and 102 are attached to the liquid cooling jacket 13 via one copper plate 12, and the liquid cooling jacket 13 is attached to the support portion of the holding mechanism 303. Thus, by using the copper plate 12, the liquid cooling jacket 13 and the holding mechanism 303 in common, the configuration can be simplified and the cost can be reduced, and the position adjustment work of the light source units 101 and 102 can be simplified. can do. Furthermore, the distance between the laser beams L1 and L2 can be appropriately shortened as compared with the case of FIG.

  FIG. 3 shows the arrangement of the light source units 101 and 102 and the emission state of the laser beams L01 and L02, but the arrangement of the light source units 103 and 104 and the emission state of the laser beams L03 and L04 are the same. .

  By configuring the illumination device as described above, the beams of the laser beams L01, L02, L03, and L04 emitted from the light source units 101, 102, 103, and 104 at the position on the plane P shown in FIG. The shape can be made uniform. Therefore, when the fly-eye lens is disposed on the rear side in the third direction, as shown in FIG. 4, the laser light L01, L02, L03, and L04 are emitted without leaving the effective area of the fly-eye lens. It can be incident on a fly-eye lens. Therefore, according to the illuminating device which concerns on this Embodiment, the uniforming effect of the light by a fly eye lens can be exhibited appropriately, without reducing the utilization efficiency of illumination light.

<Other embodiments>
FIG. 5 is a diagram illustrating an optical system of an illumination apparatus according to another embodiment. FIG. 4A is a top view of the lighting device, and FIG. 4B is a front view of the lighting device.

  As illustrated, in the optical system of the illumination apparatus according to the present embodiment, the number of light source units arranged in the illumination apparatus is increased as compared with the above. That is, in the embodiment of FIG. 2 described above, two light source units are arranged opposite to the mirror surfaces 201a and 201b of the prism mirror 201. However, in the embodiment of FIG. 16 light source units are arranged in a matrix so as to face 211a and 211b. FIG. 6A shows the uppermost light source units 111 to 118 among the 32 light source units arranged in a matrix, and FIG. 6B shows the light source unit in the foremost row seen from the front side. 111, 121, 131, 141 and light source units 115, 125, 135, 145 are shown.

  In FIG. 5, the light source units at each stage are arranged linearly in the Z-axis direction, and the light source units in each row are arranged linearly in the Y-axis direction. Each of these 32 light source units has the configuration of FIG. 1 as in the above embodiment. Further, these 32 light source units are provided with a semiconductor laser array 11 having the same optical characteristics (laser wavelength, spread angle, etc.).

  The 16 light source units arranged on the mirror surface 211a side emit laser light in the same direction (first direction) parallel to the X axis in the figure, and the emission position of the laser light is the first light source unit. It arrange | positions so that it may be located on the common plane perpendicular | vertical to a direction. Further, the 16 light source units arranged on the mirror surface 211b side emit laser light in a second direction opposite to the first direction, and the emission position of the laser light is in the second direction. It is arranged to lie on a vertical common plane. Further, the 16 light source units arranged on the mirror surface 211a side and the 16 light source units arranged on the mirror surface 211b side are individually arranged so that the emission positions of the laser beams face each other.

  The prism mirror 211 has a shape whose cross section is a right-angled isosceles triangle, and two surfaces sandwiching a perpendicular vertex angle are mirror surfaces 211a and 211b. The prism mirror 211 is a laser beam emitted from the 32 light source units (laser beams L11 to L18 emitted from the uppermost light source unit are shown in FIG. 5A). The axes are arranged so as to be 45 ° with respect to the mirror surfaces 211a and 211b, respectively. That is, the angle α obtained by dividing the apex angle of the prism mirror 201 in the YZ plane in FIG. Therefore, these laser beams are reflected by the mirror surfaces 211a and 211b and travel in the third direction (Z-axis direction in the figure).

  Further, the 32 light source units and the prism mirror 211 are arranged so that the optical path lengths from the respective light source units to the plane P perpendicular to the third direction are the same. That is, when the dimensions of the respective parts are set as shown in FIG. 6A, D1 = D2, E1 = E2, F1 = F2, G1 = G2, J1 = I1 = H1 = J2 = I2 = H2, D1 = G1 + J1 + I1 + H1 = F1 + I1 + H1 = E1 + H1, D2 = G2 + J2 + I2 + H2 = F2 + I2 + H2 = E2 + H2. Here, D1, D2, E1, E2, F1, F2, G1, and G2 are optical path lengths from the light source units in each column to the reflecting surfaces 211a and 211b, respectively, and H1, I1, J1, H2, I2 and J2 are distances between the light emitting points between the light source units 1 in adjacent rows, respectively.

  FIG. 6 is a diagram schematically illustrating an arrangement state of 16 light source units on the mirror surface 211a side and a laser light emission state.

  Laser light emitted from these 16 light source units 111-114, 121-124, 131-134, 141-144 (a set of laser light emitted from each semiconductor laser element 11b in the semiconductor laser array 11) Since they have the same divergence angle, the beam shape of these laser beams increases as they propagate.

  In the configuration example of FIG. 6, 16 light source units are individually held by holding mechanisms 311 to 314, 321 to 324, 331 to 334, and 341 to 344. Each holding mechanism 311 to 314, 321 to 324, 331 to 334, 341 to 344 has a mechanism capable of adjusting the position of the support portion that supports the corresponding light source unit in the X, Y, and Z directions in the drawing. . By adjusting this mechanism, the light emission positions of the light source units 111 to 114, 121 to 124, 131 to 134, and 141 to 144 are adjusted in the X, Y, and Z directions in the drawing.

  FIG. 7 shows a configuration in which the light source units at each stage are held by a common holding mechanism 310, 320, 330, 340. In this case, each of the holding mechanisms 310, 320, 330, and 340 has a mechanism that can adjust the positions of the light source units 111 to 114, 121 to 124, 131 to 134, and 141 to 144 in the X and Y directions in the drawing. ing.

  In addition, in the configuration of FIG. 7, as in the case of FIG. 3B, a common copper plate 12 and a liquid cooling jacket 13 are arranged as cooling means for the light source units at each stage. That is, the four light source units at each stage are attached to the liquid cooling jacket 13 via one copper plate 12, and the liquid cooling jacket 13 is attached to the support portion of the corresponding holding mechanism 310, 320, 330, 340. ing. Thus, by using the copper plate 12, the liquid cooling jacket 13, and the holding mechanisms 310, 320, 330, and 340 in common, the configuration can be simplified and the cost can be reduced. Position adjustment work can be simplified. Furthermore, compared with the case of FIG. 6, the distance between the laser beams emitted from the light source units at each stage can be appropriately shortened.

  6 and 7 show the arrangement of the 16 light source units on the mirror surface 211a side and the emission state of the laser light. The arrangement of the 16 light source units on the mirror surface 211b side and the laser light are shown. This is also the same as the emission state.

  By configuring the illumination device as described above, the beam shapes of the laser beams emitted from these 32 light source units can be made uniform at the position of the plane P shown in FIG. Therefore, when the fly-eye lens is arranged on the rear side in the third direction, as shown in FIG. 8, each laser beam is allowed to enter the fly-eye lens without leaving the effective area of the fly-eye lens. Can do. Therefore, according to the illuminating device which concerns on this Embodiment, the uniforming effect of the light by a fly eye lens can be exhibited appropriately, without reducing the utilization efficiency of illumination light. In addition, since 32 light source units are used as the light emitting sources, it is possible to achieve higher brightness of the illumination light.

  FIG. 9 is a diagram illustrating an optical system of an illumination apparatus according to another embodiment. FIG. 2A is a top view of the lighting device, and FIGS. 2B and 2C are front views of the lighting device. FIG. 5B shows a state in which the laser light emitted from the light source units 151 and 153 is incident on the prism mirror 221. FIG. 5C shows the laser light emitted from the light source units 152 and 154. A state of being incident on 222 is shown.

  As shown in the drawing, the optical system of the illumination device according to this embodiment includes four light source units 151 to 154 and two prism mirrors 221 and 222. Each of the light source units 151 to 154 has the configuration shown in FIG. 1, and the semiconductor laser array 11 having the same optical characteristics (laser wavelength, divergence angle, etc.) is disposed in these light source units 151 to 154. .

  Among these, the light source units 151 and 152 emit laser light in the same direction (first direction) parallel to the X axis in the figure, and the emission position of the laser light is shifted in the first direction. . The light source units 153 and 154 emit laser light in a second direction opposite to the first direction, and the emission position of the laser light is shifted in the second direction. Further, the light source units 151 and 153 are arranged so that the light emission positions of the laser beams face each other, and the light source units 152 and 154 are arranged so that the light emission positions of the laser lights face each other.

  The prism mirrors 221 and 222 have a shape whose cross section is a right isosceles triangle, and have mirror surfaces 221a and 221b and mirror surfaces 222a and 222b, respectively. The prism mirror 221 is arranged so that the optical axes of the laser beams L51 and L53 emitted from the light source units 151 and 153 are 45 ° with respect to the mirror surfaces 221a and 221b, respectively. Are arranged so that the optical axes of the laser beams L52 and L54 emitted from the laser beam are 45 ° with respect to the mirror surfaces 222a and 222b, respectively. That is, the angle α obtained by dividing the apex angle of the prism mirrors 221 and 222 in the YZ plane in FIG. Therefore, the laser beams L51 to L54 are reflected by the mirror surfaces 221a and 221b and the mirror surfaces 222a and 222b and travel in the third direction (Z-axis direction in the figure).

  Further, the light source units 151 to 154 and the prism mirrors 221 and 222 are arranged so that the optical path lengths from the light source units 151 to 154 to the plane P perpendicular to the third direction are the same. That is, when the dimensions of the respective parts are set as shown in FIG. 5A, K1 = K2, L1 = L2, M1 = M2, K1 = L1 + M1, and K2 = L2 + M2. Here, K1 and K2 are optical path lengths from the light source units 151 and 153 to the reflecting surfaces 221a and 221b, respectively, L1 and L2 are optical path lengths from the light source units 152 and 154 to the reflecting surfaces 222a and 222b, respectively, and M1 is The distance between the light emitting points of the light source units 151 and 152, M2, is the distance between the light emitting points of the light source units 153 and 154.

  By arranging the light source units 151 to 154 and the prism mirrors 221 and 222 as described above, the laser beams L51, L52, L53, and L54 emitted from the light source units 151, 152, 153, and 154 at the position of the plane P are arranged. The beam shape can be made uniform. Therefore, when the fly-eye lens is arranged on the rear side in the third direction, the laser light L51, L52, L53, and L54 is fly-eyeed without leaving the effective area of the fly-eye lens, as in FIG. It can enter the lens. Therefore, according to the illuminating device according to this embodiment, as in the case of FIG. 2 described above, the effect of uniformizing the light by the fly-eye lens can be appropriately exhibited without reducing the use efficiency of the illumination light.

<Projector configuration example>
FIG. 10 is a diagram showing an optical system of a projector using the illumination device.

  In the figure, reference numerals 501, 506 and 511 denote illumination devices. The illumination devices 501, 506, and 511 emit illumination light in the red wavelength band, the green wavelength band, and the blue wavelength band, respectively. Among these, the illumination device having the above-described configuration can be used as the illumination device 501 for red light.

  The light source (light source unit) used for the lighting devices 506 and 511 is different from the configuration shown in FIG. At present, the laser light in the green wavelength band and the blue wavelength band is generated by converting the wavelength of laser light in other wavelength bands. Therefore, the light source unit that emits green light and blue light includes an optical system that converts the wavelength of laser light in other wavelength bands into the green wavelength band and the blue wavelength band. The light source unit that emits green light and blue light has a configuration in which the optical system and the cooling unit are integrated. Therefore, in the illumination devices 506 and 511, for example, each light source unit in FIGS. 2, 5, and 9 is a light source unit for green light and blue light in which the wavelength conversion optical system and the cooling unit are integrated. Is replaced by When configured in this manner, the optical path length from each light source unit to the fly-eye lens is constant, as described above, so that the beam shape of each laser beam when the fly-eye lens is incident is made uniform, and the same effect as described above is obtained. Played.

  Red illumination light emitted from the illumination device 501 is incident on a pair of fly-eye lenses 502. The red illumination light that has passed through the fly-eye lens 502 is incident on the liquid crystal panel 505 via the condenser lenses 503 and 504. Further, the green illumination light emitted from the illumination device 506 is incident on the pair of fly-eye lenses 507. The green illumination light that has passed through the fly-eye lens 507 is incident on the liquid crystal panel 510 via the condenser lenses 508 and 509. Further, the blue illumination light emitted from the illumination device 511 is incident on the pair of fly-eye lenses 512. The blue illumination light that has passed through the fly-eye lens 512 is incident on the liquid crystal panel 515 via the condenser lenses 513 and 514.

  Polarizing plates (not shown) are disposed on the light incident side and the light emitting side of the liquid crystal panels 505, 510, and 515, respectively. The red illumination light, the green illumination light, and the blue illumination light incident on the liquid crystal panels 505, 510, and 515 via the incident side polarizing plate are modulated by the liquid crystal panels 505, 510, and 515, respectively, and then output on the output side polarizing plate. Through the dichroic prism 516.

  Thereafter, the red illumination light, the green illumination light, and the blue illumination light are combined by the dichroic prism 516 and are incident on the projection lens 517 as image light. The projection lens 517 includes a lens group for forming image light on the projection surface, and an actuator for adjusting a zoom state and a focus state of the projected image by displacing a part of the lens group in the optical axis direction. It has. Accordingly, the images displayed on the liquid crystal panels 505, 510, and 515 are enlarged and projected on the screen.

  According to the configuration of FIG. 10, laser beams from a plurality of light source units arranged in the illumination devices 501, 506, and 511 can be incident on the fly-eye lenses 502, 507, and 512 with a uniform beam shape. Therefore, by appropriately adjusting the distance between the lighting devices 501, 506, and 511 and the fly-eye lenses 502, 507, and 512, each laser beam is incident on the fly-eye lenses 502, 507, and 512 without leaving an effective area. Can be made. Therefore, according to the configuration of FIG. 10, the light equalization effect by the fly-eye lenses 502, 507, and 512 can be appropriately exhibited without reducing the utilization efficiency of red, green, and blue illumination light. Therefore, it is possible to realize high brightness of the image projected on the screen.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications other than those described above can be made to the embodiments of the present invention.

  For example, in the above embodiment, an example in which four and thirty-two light source units are arranged has been shown, but the number of light source units arranged in the illumination device is not limited to this, and the prism mirror The number can also be changed as appropriate according to the number of light source units. However, when the number of light source units and prism mirrors is changed from the above, it is necessary to adjust the arrangement of the light source units and prism mirrors so that the optical path length from each light source unit to the fly-eye lens is constant.

  When the light source unit shown in FIG. 1 is used, since the spread angle of the laser beam is large, it is assumed that the beam shape of the laser beam when entering the fly-eye lens is too large for the fly-eye lens. However, in this case, a lens for suppressing the divergence angle may be disposed on the emission side of the light source unit.

  For example, in the configuration shown in FIGS. 2 and 3, a common cylindrical lens for converging laser light in the Y-axis direction may be disposed for the light source units 101 and 102, and the same cylindrical lens may be used as the light source. What is necessary is just to arrange | position with respect to the knits 103 and 104. In this case, the positional relationship between the light source units 101 and 102 and the cylindrical lens is the same as the positional relationship between the light source units 103 and 104 and the cylindrical lens. Thus, the beam shapes of the laser beams L01, L02, L03, and L04 on the plane P in FIG. 2A are smaller in the Y-axis direction than when no cylindrical lens is provided. Further, since the converging action in the Y-axis direction given from the cylindrical lens is the same with respect to the laser beams L01, L02, L03, and L04, even if the cylindrical lens is arranged in this way, the beam shape of these laser beams is Become equal to each other.

  Further, in the configuration examples shown in FIGS. 2, 5, and 9, the apex angle α of the prism mirror is set to 45 degrees. However, the angle α is not limited to 45 degrees and can be changed to other angles as appropriate. It is. However, the arrangement of the light source unit (incident angle of the laser beam axis with respect to the mirror surface) is appropriately adjusted according to the apex angle α of the prism mirror so that the laser light reflected by the prism mirror is directed in the same direction. There is a need to. Also in this case, it is necessary to adjust the arrangement of the light source unit and the prism mirror so that the optical path length from each light source unit to the fly-eye lens is constant.

  In addition, the embodiment of the present invention can be variously modified as appropriate within the scope of the technical idea shown in the claims.

The figure which shows the structure of the light source unit which concerns on embodiment The figure which shows the structure of the illuminating device which concerns on embodiment The figure which shows arrangement | positioning of the light source unit which concerns on embodiment, and the state of a laser beam The figure explaining the effect of the illuminating device which concerns on embodiment The figure which shows the structure of the illuminating device which concerns on other embodiment. The figure which shows the arrangement | positioning of the light source unit which concerns on other embodiment, and the state of a laser beam The figure which shows the arrangement | positioning of the light source unit which concerns on other embodiment, and the state of a laser beam The figure explaining the effect of the illuminating device which concerns on embodiment The figure which shows the structure of the illuminating device which concerns on other embodiment. The figure which shows the structure of the projector which concerns on embodiment The figure explaining the subject of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Semiconductor laser array 12 ... Copper plate 13 ... Liquid cooling jacket 101, 102, 103, 104 ... Light source unit 201 ... Prism mirror 111, 112, 113, 114 ... Light source unit 115, 116, 117, 118 ... Light source unit 121, 122 , 123, 124... Light source unit 131, 132, 133, 134... Light source unit 141, 142, 143, 144... Light source unit 125, 135, 145 ... Light source unit 211 ... Prism mirror 151, 152, 153, 154. , 222 ... Prism mirrors 501, 506, 511 ... Illumination devices 502, 507, 512 ... Fly-eye lenses 505, 510, 515 ... Liquid crystal panel 517 ... Projection lens

Claims (3)

A first light source group that emits light in a first direction;
A second light source group that emits light in a second direction;
Reflecting means for aligning the traveling direction of the light emitted from the first light source group and the second light source group in the third direction and making the light incident on the fly-eye lens,
The first light source group is disposed in a common plane perpendicular to the first direction, and the second light source group is disposed in a common plane perpendicular to the second direction;
The light emitting position of the first light source group and the light emitting position of the second light source group are arranged so as to face each other, and the reflecting means has a shape whose cross section is a right isosceles triangle, Arranged between the first light source group and the second light source group;
Further, each of the cylindrical lenses for converging the light emitted from the first light source group and converging the light emitted from the second light source group is disposed,
The beam shape of each light incident on the fly-eye lens from the first light source group and the second light source group is made uniform, and the first light source group does not leave an effective area of the fly-eye lens. The first light source group, the second light source group, and the reflecting means are arranged so that light enters the fly-eye lens from the second light source group.
A lighting device characterized by that. In claim 1,
Each of the first light source group and the second light source group includes a common cooling unit.
A lighting device characterized by that. The lighting device according to claim 1 or 2,
A light modulation element that modulates light via the fly-eye lens based on a video signal;
A projection lens that projects the light modulated by the light modulation element;
A projection display apparatus characterized by comprising:

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