Light source device and projection device

Abstract

To provide a light source device that can be constructed in compact size, and a projection device that is provided with this light source device.SOLUTION: A light source device 60 comprises: a laser diode 71; a reflection MLA 100 which has a micro-lens array 102 and a reflection mirror 104 and reflects the light entered from the side of the micro-lens array 102 that is opposite the reflection mirror 104 to the micro-lens array 102 side by the reflection mirror 104; and an optical member 80 which reflects the light entered from the laser diode 71 toward the reflection MLA 100 or passes it through, and reflects or passes through the light entered from the reflection MLA 100. The reflection MLA 100 is located so that the light reflected by the reflection mirror 104 is head to the optical member 80.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a light source device and a projection device. [Background technology]

[0002] Conventionally, there has been known a projection device that provides a microlens array on the optical path of light irradiated from a light source toward a display element to homogenize the light irradiated toward the display element. For example, Patent Document 1 discloses a projector that includes a light source device, an illumination optical system, an image forming element, and a projection optical system. This projector is configured so that light emitted from a laser light source passes through an optical element made of microlenses. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-51736 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in a projection device in which a microlens array is provided on the optical path of light emitted from a light source as in Patent Document 1, the optical path from the light source to the microlens array tends to be long in order to adjust the illumination area of ​​the light incident on the microlens array, and the optical path from the microlens array to the display element tends to be long in order to bundle the light emitted from the microlens array toward the display element, making it difficult to miniaturize the device.

[0005] In view of the above, an object of the present invention is to provide a light source device that can be made smaller, and a projection device that includes this light source device. [Means for solving the problem]

[0006] The light source device of the present invention comprises a light source, a reflective lens member having a microlens array and a reflective mirror, and reflecting light incident from the side opposite the reflective mirror of the microlens array toward the microlens array using the reflective mirror, and an optical member that guides light incident from the light source toward the reflective lens member and reflects or transmits light incident from the reflective lens member, and the reflective lens member is positioned so that light reflected by the reflective mirror is directed toward the optical member.

[0007] The projection device of the present invention comprises the above-mentioned light source device, a display element that generates image light, a projection optical system that projects the image light emitted from the display element onto a projection target, and a control unit that controls the light source device and the display element, and the optical element reflects or transmits light incident from the reflective lens element toward the display element. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a light source device that can be made smaller in size, and a projection device that includes this light source device. [Brief explanation of the drawings]

[0009] [Figure 1] 2 is a diagram showing functional circuit blocks of the projection device according to the first embodiment. FIG. [Figure 2] 1 is a plan view schematically illustrating the internal structure of a projection device according to a first embodiment. [Figure 3] 2 is a schematic plan view showing the manner in which light is emitted and incident in the light source device of the projection device according to the first embodiment. FIG. [Figure 4] FIG. 2 is a schematic diagram showing the general configuration of a reflective MLA of the projection device according to the first embodiment. [Figure 5] 10 is a plan view schematically illustrating the manner in which light is emitted and incident in a light source device of a projection device according to a second embodiment. FIG. [Figure 6] 10 is a schematic plan view showing the manner in which light is emitted and incident in a light source device of a projection device according to a third embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] A first embodiment of the present invention will be described below with reference to Figures 1 to 4. Figure 1 is a functional circuit block diagram of a projection device 10. The projection device control unit is made up of a CPU including an image conversion unit 23 and a control unit 38, a front-end unit including an input / output interface 22, a display encoder 24, and a display drive unit 26. Image signals of various standards input from an input / output connector unit 21 are converted by the image conversion unit 23 via the input / output interface 22 and system bus SB to unify them into image signals of a predetermined format suitable for display, and then output to the display encoder 24.

[0011] The display encoder 24 expands and stores the input image signal in the video RAM 25, generates a video signal from the stored contents of the video RAM 25, and outputs the video signal to the display driver 26. The display driver 26 drives a display element 50 such as a DMD, which is a spatial light modulator (SOM), at an appropriate frame rate in response to the image signal output from the display encoder 24.

[0012] The projection device 10 forms an optical image with the light reflected from the display element 50 by irradiating a light beam emitted from the light source device 60 onto the display element 50 via a light guide optical system 170 (see FIG. 2) described later, and projects and displays the image on a projection target such as a screen (not shown) via a projection optical system 220 (see FIG. 2) described later. A movable lens group 235 of the projection optical system 220 can perform zoom adjustment and focus adjustment by driving a lens motor 45.

[0013] The image compression / expansion unit 31 performs a recording process in which the luminance signal and color difference signal of the image signal are compressed by processes such as ADCT and Huffman coding, and the data is sequentially written to a memory card 32, which is a removable recording medium. Furthermore, the image compression / expansion unit 31 reads image data recorded on the memory card 32 in the playback mode, expands each image data constituting a series of moving images on a frame-by-frame basis, and outputs the expanded data to the display encoder 24 via the image conversion unit 23. Thus, the image compression / expansion unit 31 can output moving images, etc., based on the image data stored in the memory card 32.

[0014] The control unit 38 controls the operation of each circuit in the projection device 10, and is composed of a CPU, a ROM that permanently stores operation programs such as various settings, and a RAM used as a work memory.

[0015] The key / indicator section 37 is composed of main keys and indicators provided on the housing. Operation signals from the key / indicator section 37 are sent directly to the control section 38. In addition, key operation signals from the remote controller are received by the Ir receiving section 35, demodulated into code signals by the Ir processing section 36, and output to the control section 38.

[0016] The control unit 38 is connected to an audio processing unit 47 via a system bus SB. The audio processing unit 47 includes a sound source circuit such as a PCM sound source, and converts audio data into analog data in the projection mode and playback mode, driving a speaker 48 to emit amplified sound.

[0017] The control unit 38 controls the light source control circuit 41. The light source control circuit 41 individually controls the operation of the light emitting device 70 (see FIG. 2) in the light source device 60 so that light in a predetermined wavelength band required for image generation is emitted from the light source device 60.

[0018] Furthermore, the control unit 38 causes the cooling fan drive control circuit 43 to detect temperatures using a plurality of temperature sensors provided in the light source device 60, etc., and controls the rotation speed of the cooling fan 56 based on the results of this temperature detection. The control unit 38 also controls the cooling fan drive control circuit 43 to continue rotating the cooling fan 56 using a timer or the like even after the power to the projection device 10 main body is turned off, or to turn off the power to the projection device 10 main body depending on the results of temperature detection by the temperature sensors.

[0019] Next, the internal structure of the projection device 10 will be described with reference to Fig. 2. Fig. 2 is a schematic plan view showing the internal structure of the projection device 10. Here, the housing of the projection device 10 is formed in a substantially box shape and includes an upper panel and a lower panel (not shown), a front panel 12, a rear panel 13, a right panel 14, and a left panel 15. The projection device 10 also has a projection opening 12a on the front side. In the following description, the left and right of the projection device 10 refer to the left and right directions when the projection opening 12a is used to view the projection target in the projection direction, and the front and rear refer to the front and rear directions along the traveling direction of the light beam when projected from the projection device 10 onto the subject.

[0020] The projection device 10 includes a control circuit board 242 near the left panel 15. This control circuit board 242 includes a power circuit block, a light source control block, and the like. The projection device 10 also includes a light source device 60 located approximately in the center of the projection device 10. Between the light source device 60 and the right panel 14, a power connector 57, a first heat sink 130, a cooling fan 240, and the like are arranged. In addition, a display element 50 is provided on the left side of the light source device 60. The display element 50 is connected to a second heat sink 190 via a heat pipe (not shown).

[0021] The light source device 60 has a light output device 70 arranged on the rear panel 13 side at approximately the center in the left-right direction of the projection device 10. The light output device 70 includes a pair of laser diodes (light sources) 71 configured to output red wavelength band light, green wavelength band light, and blue wavelength band light. Each laser diode 71 is a so-called MCP (Multi Chip Package) that includes a red laser diode that outputs red wavelength band light, a green laser diode that outputs green wavelength band light, and a blue laser diode that outputs blue wavelength band light in a single package, thereby making the light source device 60 more compact. In this embodiment, the light output from each laser diode 71 is all S-polarized and aligned.

[0022] The light source device 60 is provided with a light source optical system 140 that guides light emitted from each laser diode 71 and focuses the light on the incident surface of a third condenser lens 173 (described later). The light source optical system 140 has an optical member 80, a reflective microlens array (reflective lens member) (hereinafter referred to as the "reflective MLA 100"), a first condenser lens 141, and a second condenser lens (convex lens member) 142. The optical member 80 includes a polarizing beam splitter (hereinafter referred to as the "polarizing BS 82") and a quarter-wave plate 84. The light source device 60 is also provided with a light-guiding optical system 170 that guides light from the light source optical system 140 to a projection optical system 220 (described later).

[0023] The polarizing BS82 constituting the optical member 80 is a plate-type plate that reflects or transmits incident light depending on the polarization direction of the light. Specifically, the polarizing BS82 reflects S-polarized light and transmits P-polarized light. The polarizing BS82 is disposed with one plate surface tilted at approximately 45° toward each laser diode 71 and the reflecting MLA 100. The polarizing BS82 is disposed so that S-polarized light emitted from each laser diode 71 is incident on it and the incident S-polarized light is reflected toward the reflecting MLA 100. The optical member 80 is also disposed so that light reflected by the reflecting MLA 100 toward the optical member 80 and transmitted through the optical member 80 (polarizing BS82, ¼ wavelength plate 84) is directed toward the display element 50.

[0024] The quarter-wave plate 84 constituting the optical member 80 is provided on the right side of the polarized light BS82 (on the right side in the direction in which the light L1 emitted from the laser diode 71 travels toward the polarized light BS82) and on the optical path between the polarized light BS82 and the reflecting MLA 100. The quarter-wave plate 84 converts the linearly polarized S-polarized light incident from the polarized light BS82 into circularly polarized light, which is output toward the reflecting MLA 100. The quarter-wave plate 84 also converts the circularly polarized light reflected by the reflecting MLA 100 and incident from the reflecting MLA 100, as will be described later, into linearly polarized P-polarized light, which is output toward the polarized light BS82.

[0025] Here, in this embodiment, as described above, the light emitted from each laser diode 71 is all S-polarized light, but if the polarization directions of the light emitted from each laser diode 71 are different from each other, a half-wave plate may be provided on the output side of the laser diode 71 that emits P-polarized light so that the polarization directions of the light emitted from each laser diode 71 and incident on the polarized light BS82 are aligned to S-polarized light.

[0026] The reflective MLA 100 is configured by combining a microlens array 102 and a reflecting mirror 104. Light incident from the side opposite the reflecting mirror 104 side of the microlens array 102 is reflected toward the microlens array 102 by the reflecting mirror 104. Specifically, as shown in FIG. 4 , in the reflective MLA 100, the reflecting mirror 104 is positioned so that its reflecting surface 104a is a distance D2, which is half the focal length D1 of each lens constituting the microlens array 102, away from the incident surface 102a of each lens constituting the microlens array 102. The reflective MLA 100 configured in this manner homogenizes light that enters the incident surface 102a of each lens constituting the microlens array 102 and is reflected by the reflecting surface 104a of the reflecting mirror 104, in the same manner as light that passes through a normal microlens array. The reflective MLA 100 homogenizes light incident from the quarter-wave plate 84 side and reflects it back toward the quarter-wave plate 84 side.

[0027] The first condenser lens 141 is a biconcave lens arranged on the optical path between each laser diode 71 and the polarized light BS 82, and controls the inclination of the light emitted from each laser diode 71 to guide the light toward the polarized light BS. The second condenser lens 142 is a biconvex lens arranged on the optical path between the quarter-wave plate 84 and the reflective MLA 100, and converts the light spread by the first condenser lens 141 into parallel light and makes it incident on the incident surface 102a of the microlens array 102.

[0028] Next, the light-guiding optical system 170 will be described. The light-guiding optical system 170 has a third condenser lens 173 and an RTIR prism (second prism member) 174. The third condenser lens 173 is located to the left of the polarized light BS 82 (left side in the direction in which the light L1 emitted from the laser diode 71 travels toward the polarized light BS 82) and is disposed on the optical path between the polarized light BS 82 and the RTIR prism 174. The third condenser lens 173 controls the inclination of the light emitted from the polarized light BS 82 to form an image on the display element 50. The third condenser lens 173 is, for example, a concave lens. The RTIR prism 174 is disposed on the optical path between the third condenser lens 173 and the display element 50 with a reflection-transmission surface 174a, which reflects or transmits light depending on the angle of incidence of the incident light, facing the optical member 80.

[0029] The projection optical system 220 has an RTIR prism 174, a movable lens group 235, and a fixed lens group 225. Image light of the display element 50 emitted via the RTIR prism 174 is emitted from the projection opening 12a via the movable lens group 235 and the fixed lens group 225. The RTIR prism 174 is disposed so that light incident on the reflective / transmissive surface 174a from the third condenser lens 173 side is incident on the reflective / transmissive surface 174a at an angle of incidence smaller than the angle at which total reflection occurs, and light incident on the reflective / transmissive surface 174a from the display element 50 side is incident on the reflective / transmissive surface 174a at an angle of incidence at which total reflection occurs. The projection device 10 according to this embodiment has the above-described configuration.

[0030] Next, the incidence and emission of light in each component constituting light source device 60 will be described with reference to Fig. 3. Note that, hereinafter, light emitted from each laser diode 71 and reaching the reflection MLA 100 will be referred to as "outgoing light L1 (shown by a solid line in Fig. 3)," and light reflected by the reflection MLA 100 and reaching the display element 50 will be referred to as "returning light L2 (shown by a dashed line in Fig. 3)." The S-polarized outgoing light L1 emitted from each laser diode 71 of light emitting device 70 has its inclination controlled by passing through first condenser lens 141, and is incident on polarized light BS82.

[0031] The outgoing light L1 incident on the polarized light BS 82 is reflected by the polarized light BS 82 toward the quarter-wave plate 84 (the reflection MLA 100 side). The outgoing light L1 reflected toward the quarter-wave plate 84 side is converted into circularly polarized light by passing through the quarter-wave plate 84 and enters the second condenser lens 142. The light that is spread by the first condenser lens 141 by passing through the second condenser lens 142 is converted into parallel light within the range of the incident surface 102a of the microlens array 102 and enters the reflection MLA 100. This makes it possible to eliminate light that reaches the reflection mirror 104 without entering the microlens array 102, allowing the microlens array 102 to be used effectively.

[0032] The outgoing light L1 incident on the reflecting MLA 100 reaches the reflecting surface 104a of the reflecting mirror 104 from the incident surface 102a of the microlens array 102, is reflected by the reflecting surface 104a toward the second condenser lens 142 (the optical member 80 side), and is emitted as the returning light L2 from the incident surface 102a of the microlens array 102. In this way, the outgoing light L1 incident on the reflecting MLA 100 passes through the microlens array 102 before and after being reflected by the reflecting mirror 104, and is then incident again on the second condenser lens 142 as the uniformed returning light L2.

[0033] The return path light L2 incident on the second collecting lens 142 is converted into parallel light by passing through the second collecting lens 142 and then incident on the quarter-wave plate 84 again. By passing through the quarter-wave plate 84, the light is converted into P-polarized linearly polarized light and then incident on the polarized light BS82 again. The return path light L2 incident on the polarized light BS82 again passes through the polarized light BS82 and then incident on the third collecting lens 173. The return path light L2 incident on the third collecting lens 173 has its tilt controlled by passing through the third collecting lens 173 and then incident on the RTIR prism 174.

[0034] The return light L2 incident on the RTIR prism 174 from the third condenser lens 173 side passes through the RTIR prism 174 and reaches the display element 50, where image light is generated in the display element 50. The image light generated in the display element 50 is incident on the reflective / transmissive surface 174a of the RTIR prism 174 and is totally internally reflected by the reflective / transmissive surface 174a, and is emitted toward the movable lens group 235 and fixed lens group 225.

[0035] The outgoing light L1 and the returning light L2 follow the optical paths described above, and thus their optical paths overlap between the optical member 80 and the reflecting MLA 100. This allows the light source device 60 to be miniaturized while ensuring the required optical path lengths for the outgoing light L1 and the returning light L2. As a result, the projection device 10 can be miniaturized while providing the microlens array 102 on the optical path.

[0036] Furthermore, by configuring the outgoing light L1 and the returning light L2 so that their optical paths partially overlap as described above, the second focusing lens 142 can be used in common for the outgoing light L1 and the returning light L2, so that the number of focusing lenses can be reduced compared to the conventional configuration in which focusing lenses are provided before and after passing through the microlens array, thereby reducing the number of components.

[0037] As described above, the light source device 60 of this embodiment comprises a laser diode 71, a microlens array 102, a reflecting MLA 100 which has the microlens array 102 and a reflecting mirror 104 and which reflects light incident on the microlens array 102 from the side opposite the reflecting mirror 104 side towards the microlens array 102 side by the reflecting mirror 104, and an optical element 80 which reflects or transmits light incident from the laser diode 71 towards the reflecting MLA 100 and reflects or transmits light incident from the reflecting MLA 100, and the reflecting MLA 100 is arranged so that the light reflected by the reflecting mirror 104 is directed towards the optical element 80.

[0038] In the light source device 60 according to the present embodiment configured as described above, by disposing the reflecting MLA 100, it is possible to overlap at least a portion of the optical path of light from the optical member 80 toward the reflecting MLA 100 and the optical path of light reflected by the reflecting MLA 100 toward the optical member 80 between the optical member 80 and the reflecting MLA 100, thereby shortening the length of the optical path compared to conventional light source devices in which a microlens array is disposed on the optical path so that the light passes through the microlens array. This makes it possible to reduce the size of the light source device 60 while providing the microlens array 102.

[0039] Furthermore, in the light source device 60 according to this embodiment, the reflective MLA 100 has the reflective mirror 104 located at a position that is a distance D2 that is half the focal length D1 of the microlens array 102 away from the microlens array 102. With this configuration, light that is incident on the microlens array 102 travels the distance D2 that is half the focal length D1 to reach the reflective mirror 104, is reflected by the reflective mirror, and travels the distance D2 that is half the focal length D1 before being emitted from the microlens array 102. Therefore, the light that is emitted from the microlens array 102 can be made uniform in the same way as light that has passed through a normal microlens array.

[0040] Furthermore, in the light source device 60 according to this embodiment, the optical member 80 includes a polarized light source BS82 that reflects or transmits incident light depending on the polarization direction of the incident light, and a quarter-wave plate 84 that is provided on the optical path between the polarized light source BS82 and the reflecting MLA 100. With this configuration, light that travels from the polarized light source BS82 to the reflecting MLA 100, is reflected by the reflecting MLA 100, and reaches the polarized light source BS82 passes through the quarter-wave plate 84 twice, converting the polarization direction of the light between S-polarized light and P-polarized light. As a result, when the outgoing light source L1 is reflected by the polarized light source BS82, the returning light source L2 passes through the polarized light source BS82, and when the outgoing light source L1 passes through the polarized light source BS82, the returning light source L2 is reflected by the polarized light source BS82. Therefore, a specific configuration of the optical member 80 for reflecting or transmitting light incident from the reflecting MLA 100 can be provided.

[0041] Furthermore, in light source device 60 according to this embodiment, reflective MLA 100 is arranged so that the optical path of light traveling from optical member 80 to reflective MLA 100 overlaps with the optical path of light reflected by reflective MLA 100 and traveling to optical member 80. This configuration effectively shortens the length of the optical path compared to conventional light source devices in which a microlens array is arranged on the optical path so that the light passes through the microlens array. Therefore, light source device 60 can be further miniaturized while providing microlens array 102.

[0042] Furthermore, in the light source device 60 according to this embodiment, a second condenser lens 142 is provided on the optical path between the optical member 80 and the reflective MLA 100. With this configuration, the second condenser lens 142 can convert the light incident on the microlens array 102 into parallel light within the range of the incident surface 102a of the microlens array 102, allowing for effective use of the microlens array 102. Furthermore, since the second condenser lens 142 can be shared by both the outgoing light L1 and the returning light L2, the number of condenser lenses can be reduced compared to a conventional configuration in which condenser lenses are provided before and after transmission through the microlens array, thereby reducing the number of components.

[0043] Furthermore, the projection device 10 according to this embodiment includes the above-described light source device 60, a display element 50 that generates image light, a projection optical system 220 that projects the image light emitted from the display element 50 onto a projection target, and a control unit 38 that controls the light source device 60 and the display element 50, and the optical member 80 reflects or transmits light incident from the reflective MLA 100 toward the display element 50. This configuration makes it possible to realize a projection device 10 that is provided with a microlens array 102 yet allows the light source device 60 to be miniaturized.

[0044] Next, a second embodiment of the present invention will be described with reference to Fig. 5. As shown in Fig. 5, the projection device (light source device 260) according to the second embodiment differs from the projection device 10 of the first embodiment in the configuration of the optical member 280. Since the configuration of the projection device other than the optical member 280 is the same as that of the first embodiment, the description thereof will be omitted or simplified. Furthermore, in the projection device according to the second embodiment, members having the same configuration as those in the projection device according to the first embodiment are assigned the same reference numerals.

[0045] 5, the optical member 280 according to this embodiment includes a TIR prism (first prism member) 282. The TIR prism 282 constituting the optical member 280 is disposed on the optical path between the third collecting lens 173 and the display element 50, with the inner side of a reflective / transmissive surface 282a, which reflects or transmits light depending on the angle of incidence of the incident light, facing the laser diodes 71 and the reflecting MLA 100. The TIR prism 282 is disposed so that light incident on the reflective / transmissive surface 282a from the laser diodes 71 side is incident on the reflective / transmissive surface 282a at an angle at which light is totally reflected, and light incident on the reflective / transmissive surface 282a from the reflecting MLA 100 side is incident on the reflective / transmissive surface 282a at an angle of incidence smaller than the angle at which light is totally reflected.

[0046] Next, the incidence and emission of light in each member constituting the light source device 260 of the second embodiment will be described. The light guide mode of the outgoing light L3 emitted from each laser diode 71 of the light emitting device 70 until it reaches the optical member 80 (the reflection / transmission surface 282a of the TIR prism 282) is the same as in the first embodiment. Note that in this embodiment, the polarization direction of the light emitted from each laser diode 71 is not limited.

[0047] Outgoing light L1 incident on the reflective / transmissive surface 282a of the TIR prism 282 constituting the optical member 280 is totally internally reflected by the reflective / transmissive surface 282a toward the second collecting lens 142 (the reflecting MLA 100 side). The light guide mode of the outgoing light totally reflected toward the second collecting lens 142 side until it reaches the reflecting MLA 100, and the light guide mode of the return light L4 reflected by the reflecting MLA 100 toward the second collecting lens 142 side (the optical member 80 side) until it again reaches the optical member 80 (the reflective / transmissive surface 282a of the TIR prism 282) are the same as those in the first embodiment.

[0048] The return light L4 that is again incident on the reflective / transmissive surface 282a of the TIR prism 282 passes through the TIR prism 282 and enters the third condenser lens 173. The light guide mode of the return light L4 that is incident on the third condenser lens 173 until it reaches the display element 50, and the light guide mode of the image light generated by the display element 50 until it is emitted toward the movable lens group 235 and the fixed lens group 225, are the same as those in the first embodiment.

[0049] As described above, in the light source device 260 and projection device according to this embodiment, the optical path of light traveling from optical element 280 to reflecting MLA 100 and the optical path of light reflected by reflecting MLA 100 and traveling to optical element 280 can also be at least partially overlapped, so the length of the optical path can be shortened compared to conventional light source devices in which a microlens array is arranged on the optical path so that the light passes through the microlens array. Therefore, it is possible to reduce the size of the light source device 260 and projection device while providing the microlens array 102.

[0050] Furthermore, in the light source device 260 according to this embodiment, the optical member 280 includes a TIR prism 282 that reflects or transmits incident light depending on the angle of incidence of the incident light. According to this configuration, the TIR prism 282 can be arranged so that when outgoing light L3 is totally internally reflected at the reflective / transmissive surface 282a of the TIR prism 282, returning light L4 is transmitted through the reflective / transmissive surface 282a, and when outgoing light L3 is transmitted through the reflective / transmissive surface 282a of the TIR prism 282, returning light L4 is totally internally reflected at the reflective / transmissive surface 282a. Therefore, it is possible to provide a specific configuration of the optical member 280 that reflects or transmits light incident from the reflecting MLA 100 in a direction different from the reflecting MLA 100 side (a direction different from the direction toward the reflecting MLA 100).

[0051] Next, a third embodiment of the present invention will be described with reference to Fig. 6. As shown in Fig. 6, the projection device (light source device 360) according to the third embodiment does not include the first condenser lens 141, which is a concave lens, and differs from the projection device 10 of the first embodiment in the configuration of the optical member 380, the configuration of the RTIR prism 474, the arrangement of the third condenser lens 173, and the arrangement angle of the light output device 70. Since the configuration of the projection device other than the optical member 380 is the same as that of the first embodiment, the description thereof will be omitted or simplified. Furthermore, in the projection device according to the second embodiment, components having the same configuration as those in the projection device according to the first embodiment are denoted by the same reference numerals.

[0052] As shown in FIG. 6, the light source device 360 ​​according to this embodiment has a configuration in which the polarizing beam splitter 382 (polarizing beam splitter 382) constituting the optical member 380 is integrated with the RTIR prism 474. Specifically, the polarizing beam splitter 382 is coated on substantially the entire reflective / transmissive surface 474a of the RTIR prism 474. Furthermore, in the light source device 360, no condensing lens such as a concave lens is provided between the light emitting device 70 and the polarizing beam splitter 382. The light emitting device 70 is disposed at an angle such that the light emission direction is directed toward the RTIR prism 474, so that the light emitted from each laser diode 71 is directly incident on the polarizing beam splitter 382. Furthermore, the third condensing lens 173, which is a concave lens, is provided between the polarizing beam splitter 382 and the quarter-wave plate 84.

[0053] Next, the incidence and emission of light in each component constituting the light source device 360 ​​of the third embodiment will be described. As shown in FIG. 6, in this embodiment, S-polarized outgoing light L5 emitted from each laser diode 71 of the light output device 70 is directly incident on the polarizing BS 382 integrated with the RTIR prism 474. The outgoing light L5 incident on the polarizing BS 382 is reflected by the polarizing BS 382 toward the third condenser lens 173 (the reflecting MLA 100 side). The inclination of the outgoing light L5 incident on the third condenser lens 173 is controlled and the light is guided to the quarter-wave plate 84. The light guide mode from when the outgoing light L5 incident on the quarter-wave plate 84 is reflected by the reflecting MLA 100 to when it reaches the quarter-wave plate 84 again as the return light L6 is the same as in the first embodiment.

[0054] The return path light that has reached the quarter-wave plate 84 is converted into P-polarized light by passing through the quarter-wave plate 84 and then enters the third condenser lens 173 again. The return path light that has entered the third condenser lens 173 again has its tilt controlled again by passing through the third condenser lens 173 and enters the polarized BS 382 again. The return path light L6 that has entered the polarized BS 382 again passes through the reflective / transmissive surface 474a of the RTIR prism 474 and reaches the display element 50, where image light is generated. The light guide mode until the image light generated by the display element 50 is emitted toward the movable lens group 235 and the fixed lens group 225 is the same as in the first embodiment.

[0055] As described above, in the light source device 360 ​​and projection device according to this embodiment, a condenser lens such as a concave lens is not provided on the optical path of light from the light output device 70 between the light output device 70 and the polarized light BS 382, ​​and the light from the light output device 70 is incident on the polarized light BS 382 without passing through a condenser lens (third condenser lens 173). Furthermore, a condenser lens (third condenser lens 173) is provided on the optical path between the polarized light BS 382 and the quarter-wave plate 84. This narrows the gap between the light output device 70 and the polarized light BS 382, ​​thereby reducing the space required for the light source device 360. This allows the light source device 360 ​​and projection device to be further miniaturized.

[0056] Furthermore, the projection device according to this embodiment includes an RTIR prism 474 that reflects or transmits incident light depending on the angle of incidence of the incident light, and the polarized BS 380 constituting the optical member 380 is coated on the RTIR prism 474, which is disposed so as to guide the light that has passed through the polarized BS 380 toward the display element 50. This provides a specific configuration for guiding the light that has passed through the polarized BS 380 toward the optical display element 50 without providing a condenser lens on the optical path of the light from the polarized BS 382 between the polarized BS 382 and the RTIR prism 474. As a result, in this embodiment, the light source device 360 ​​can be made more space-saving than the light source device 60 of the first embodiment, thereby enabling further miniaturization of the projection device.

[0057] In this embodiment, a configuration in which the polarized BS380 is coated on the RTIR prism 474, thereby integrating the polarized BS380 with the RTIR prism 474, has been exemplified, but this is not limited to this, and the two may be integrated, for example, by gluing the polarized BS380 onto the RTIR prism 474.

[0058] The above-described embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments may be embodied in various other forms, and various omissions, substitutions, and modifications may be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims.

[0059] For example, in each of the above embodiments, the light source is an MCP including a blue laser diode, a red laser diode, and a green laser diode in a single package. However, the blue laser diode, the red laser diode, and the green laser diode may be arranged separately, and the optical axes of the light emitted from each laser diode may be aligned by a dichroic mirror. Also, in each of the above embodiments, the light source is a laser diode. However, the light source may be, for example, an LED. In this case, a collimator lens may be provided on the output side of the LED to limit the light emitted from the LED to a luminous flux limited to a predetermined range. [Explanation of symbols]

[0060] 60: Light source device, 71: Laser diode, 80: Optical member, 100: Reflecting MLA, 102: Microlens array, 104: Reflecting mirror

Claims

1. A light source and a reflective lens member having a microlens array and a reflective mirror, and reflecting light incident from the side opposite to the reflective mirror side of the microlens array toward the microlens array by the reflective mirror; an optical member that guides the light incident from the light source toward the reflective lens member and reflects or transmits the light incident from the reflective lens member, The reflective lens member is arranged so that the light reflected by the reflective mirror is directed toward the optical member. Light source device.

2. The reflective lens member is arranged so that an optical path of light traveling from the optical member to the reflective lens member overlaps with an optical path of light reflected by the reflective lens member and traveling to the optical member. The light source device according to claim 1 .

3. a convex lens member is provided on the optical path between the optical member and the reflecting lens member; The light source device according to claim 2 .

4. The optical member includes a polarizing beam splitter that reflects or transmits incident light depending on the polarization direction of the incident light, and a quarter-wave plate that is provided on an optical path between the polarizing beam splitter and the reflective lens member. The light source device according to claim 1 .

5. The light from the light source is incident on the polarizing beam splitter without passing through a condenser lens. The light source device according to claim 4 .

6. a condenser lens is provided on the optical path between the polarizing beam splitter and the quarter-wave plate; The light source device according to claim 5 .

7. The optical member includes a first prism member that reflects or transmits incident light depending on the incident angle of the incident light. The light source device according to claim 1 .

8. The reflective lens member is provided such that the reflective mirror is located at a distance of 1 / 2 of the focal length of the microlens array from the microlens array. The light source device according to claim 1 .

9. The light source device according to any one of claims 1 to 8, a display element for generating image light; a projection optical system that projects the image light emitted from the display element onto a projection target; a control unit that controls the light source device and the display element, The optical member reflects or transmits light incident from the reflective lens member toward the display element. Projection device.

10. a second prism member that reflects or transmits incident light according to the angle of incidence of the incident light; At least a portion of the optical member is integrated with the second prism, the second prism member is arranged to guide the light that has passed through the optical member toward the display element.

10. The projection device according to claim 9.

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