JP2020008719A - Light source device and projector - Google Patents

Abstract

To provide a light source device that includes a cooling device having an improved cooling performance compared with a prior art, and a projector.SOLUTION: A light source device 11 comprises: a light source unit 41 that has a plurality of light-emitting elements; a heat receiving plate 43a having projections 431 that are in contact with the light source unit 41, and concave parts 432 that are provided on a surface opposite to a surface on which the projections 431 are provided; a thermal diffusion member 43b that has heat pipes 433 as convex parts to be fitted to the concave parts 432; and a heat sink 43c that is in contact with the thermal diffusion member 43b. The light source unit 41 is connected to the heat sink 43c with the heat receiving plate 43a and thermal diffusion member 43b therebetween.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a light source device and a projector.

  Conventionally, a light source device having a light emitting element has been known as a light source of a projector. For example, Patent Literature 1 discloses a light source device including a plurality of light emitting elements. Since a light emitting element generates heat with light emission, heat generation tends to be remarkable when there are a plurality of light emitting elements. When such a light source device is operated, the light output may fluctuate due to heat generated in the light emitting element.

  Therefore, a cooling device may be used in the light source device in order to reduce the influence of heat generation of the light emitting element. For example, Patent Literature 2 discloses a light source device including a cooling device having a heat receiving unit, a heat pipe, and a main body (heat sink). In the cooling device, the heat generated by the light emitting element is transmitted to the main body through the heat receiving unit and the heat pipe and is radiated, thereby cooling the light source device.

JP 2017-138471 A JP 2015-40870 A

  However, the light source device described in Patent Document 2 has a problem that when the number of light emitting elements is increased, further improvement in cooling performance is required. Specifically, when the number of light emitting elements is increased, the amount of heat generated in the light source device is increased. If the cooling performance of the cooling device is not ensured against the increase in the amount of generated heat, the light emitting element is overheated, and the light output and the life of the light emitting element are likely to be reduced. That is, there has been a demand for a light source device including a cooling device having improved cooling performance as compared with the related art.

  The light source device of the present application is a heat receiving plate having a light source unit having a plurality of light emitting elements, a projection in contact with the light source unit, and a recess provided on a surface opposite to the surface on which the projection is provided, and a recess. The light source unit includes a heat diffusion member having a convex portion to be fitted and a heat sink in contact with the heat diffusion member, and the light source unit is connected to the heat sink via the heat receiving plate and the heat diffusion member.

  In the light source device described above, it is preferable that the recess is provided at a position facing the protrusion.

  In the above light source device, the heat sink preferably has a fin.

  In the above light source device, it is preferable that the heat diffusion member has a heat pipe and the fin is made of an aluminum alloy.

  In the above light source device, the heat diffusion member preferably has a vapor chamber, and the fins are preferably made of copper.

  It is preferable that the light source device includes a cooling fan that cools the heat sink.

  A projector of the present application includes the above light source device.

FIG. 1 is a schematic diagram illustrating a configuration of a projector according to a first embodiment. FIG. 2 is a perspective view illustrating an appearance of a light source device. FIG. 2 is a perspective view showing the appearance of the cooling device. FIG. 2 is an exploded perspective view showing the configuration of the cooling device. FIG. 4 is a cross-sectional view showing a fitted state between the heat receiving plate and the heat diffusion member, taken along a plane M in FIG. 3. FIG. 9 is a perspective view illustrating an appearance of a light source device according to a second embodiment. FIG. 2 is a perspective view showing the appearance of the cooling device. FIG. 2 is an exploded perspective view showing the configuration of the cooling device. FIG. 2 is an exploded perspective view showing the configuration of the cooling device. FIG. 8 is a cross-sectional view showing the fitted state of the heat receiving plate and the heat diffusion member along a surface N of FIG. 7.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiment described below describes an example of the present invention. The present invention is not limited to the following embodiments, and various modified examples implemented without departing from the spirit of the present invention are also included in the present invention. In the following drawings, the scale of each member is made different from the actual size in order to make each member recognizable.

(Embodiment 1)
<Projector>
The configuration of the projector according to the present embodiment will be described with reference to FIG. FIG. 1 is a schematic diagram illustrating a configuration of the projector according to the first embodiment.

  As shown in FIG. 1, a projector 1 according to the present embodiment includes an illumination device 2, a projection optical system 3, a first reflection mirror 5, a dichroic mirror 6, a second reflection mirror 7, a third reflection mirror 8, The light modulators 4R, 4G, and 4B and the combining optical system 10 are provided. The projector 1 has a function of projecting image light formed according to image information onto a projection surface such as a screen.

  The illumination device 2 includes a light source device 11, a first integrator optical system 12, a retardation plate 13, a polarization separation element 14, a pickup optical system 15, and a fluorescent light emitting element 16. The illumination device 2 includes a blue light superimposing lens 17 and a reflection mirror 18. Further, the illumination device 2 includes a second integrator optical system 19, a polarization conversion element 20, a yellow light superimposing lens 21, and a reflection mirror 22.

  The light source device 11 includes a collimator lens 42, a light source unit 41 that emits blue light, and a cooling device 43 that cools the light source unit 41. The cooling device 43 includes a cooling fan 49. Although not shown, the light source unit 41 includes a plurality of light emitting elements. As the light emitting element, for example, a semiconductor laser is used. The light beam K emitted from the light source unit 41 is collimated by the collimator lens 42. Details of the light source device 11 will be described later. Here, in the projector 1, the number of the light source devices 11 is not limited to one, and a plurality may be provided. In the following description, the optical axis of the light source unit 41 is referred to as an optical axis L1, and an optical axis which is in the same plane as the optical axis L1 and is orthogonal to the optical axis L1 is referred to as an optical axis L2.

  The light beam K enters the first integrator optical system 12. The first integrator optical system 12 has a first lens array 12a and a second lens array 12b. Each lens forming the first lens array 12a corresponds to each lens forming the second lens array 12b. Here, the first lens array 12a and the fluorescent light emitting element 16 on the optical axis L1 of the first lens array 12a are optically conjugate to each other. The first lens array 12a and the light modulation device 4B are optically conjugate to each other. Further, the light exit surface of the light source unit 41 and the second lens array 12b are optically conjugate to each other.

  The first integrator optical system 12, together with the pickup optical system 15, equalizes the illuminance distribution (brightness) of the light illuminating the fluorescent light emitting element 16. Further, the first integrator optical system 12 together with the blue light superimposing lens 17 uniforms the illuminance distribution of light in the image forming area of the light modulation device 4B.

  The light beam K transmitted through the first integrator optical system 12 enters the phase difference plate 13. The phase difference plate 13 is a half-wave plate. By adjusting the rotation angle of the half-wave plate, the light beam K transmitted through the phase difference plate 13 can be converted into light containing a predetermined ratio of the S-polarized light component and the P-polarized light component to the polarization beam splitter 14. It is possible.

  The polarization separation element 14 is arranged so as to form an angle of 45 degrees with the optical axis L1 and the optical axis L2. The polarization separating element 14 separates the light beam K that has passed through the phase difference plate 13 into an S-polarized component and a P-polarized component. The polarization splitting element 14 reflects light having a wavelength range different from that of the blue light beam K, that is, yellow light YL composed of fluorescent light, which will be described later, irrespective of its changed state.

  Specifically, the polarization separation element 14 reflects the S-polarized light beam BLs of the incident light (light flux K), transmits the P-polarized light beam BLp of the incident light, and converts the incident light. To separate. The light beam BLs (S-polarized light component) is reflected by the polarization separation element 14 and travels to the blue light superimposing lens 17. The light beam BLp (P-polarized light component) passes through the polarization splitting element 14 and travels to the fluorescent light emitting element 16.

  The light beam BLs emitted from the polarization beam splitter 14 enters the blue light superimposing lens 17. The blue light superimposing lens 17 superimposes the light beam BLs on the image forming area of the light modulator 4B together with the first integrator optical system 12. Thereby, the illuminance distribution of the blue light LB is made uniform. The blue light BLs transmitted through the blue light superimposing lens 17 is incident on the light modulator 4B via the reflection mirror 18, the first reflection mirror 5, and the field lens 9B.

  On the other hand, the light beam BLp passes through the polarization separation element 14 and enters the pickup optical system 15. The pickup optical system 15 has a function of condensing the light beam BLp on the phosphor layer 34 of the fluorescent light emitting element 16 and a function of picking up and parallelizing the fluorescence emitted from the phosphor layer 34. . The pickup optical system 15 includes, for example, a pickup lens 15a and a pickup lens 15b. The pickup optical system 15 superimposes the light beam BLp on the phosphor layer 34 of the fluorescent light emitting element 16 together with the first integrator optical system 12.

  The fluorescent light emitting device 16 includes a phosphor layer 34, a substrate 35 supporting the phosphor layer 34, and a driving unit 36. The substrate 35 is a disk that is rotatable around a rotation axis by a driving unit 36. The substrate 35 is made of, for example, a metal having excellent heat dissipation, such as aluminum, an aluminum alloy, or copper. The phosphor layer 34 is provided on one surface of the substrate 35 along the circumferential direction of the substrate 35. The drive unit 36 includes a drive source such as a motor for rotating the substrate 35.

  The phosphor layer 34 includes phosphor particles. The phosphor particles absorb the blue light beam BLp, convert the blue light beam BLp into yellow light YL composed of fluorescent light, and emit the yellow light YL. As the phosphor particles, for example, a YAG (Yttrium Aluminum Garnet) -based phosphor is used. As the phosphor layer 34, a phosphor layer in which phosphor particles are dispersed in an inorganic binder such as alumina, or a phosphor layer in which phosphor particles are sintered without using a binder is used.

  On the opposite side of the phosphor layer 34 from the side where the light beam BLp is incident, a reflecting portion (not shown) is provided. The reflector reflects the yellow light YL generated by the phosphor layer 34 toward the pickup optical system 15.

  The yellow light YL emitted from the phosphor layer 34 is converted by the pickup optical system 15 into parallel light. The yellow light YL emitted from the pickup optical system 15 is reflected by the polarization splitting element 14 and enters the second integrator optical system 19.

  The second integrator optical system 19, together with the superimposing lens 21 for yellow light, makes the illuminance distribution of the yellow light YL in the illuminated area uniform. The second integrator optical system 19 includes, for example, a first lens array 19a and a second lens array 19b.

  The yellow light YL that has passed through the second integrator optical system 19 enters the polarization conversion element 20. The polarization conversion element 20 has, for example, a polarization separation film and a retardation plate. The polarization conversion element 20 converts the yellow light YL into a linear change.

  The yellow light YL that has passed through the polarization conversion element 20 enters the yellow light superimposing lens 21. The yellow light superimposing lens 21 superimposes the yellow light YL emitted from the polarization conversion element 20 on the image forming area of the light modulator 4R for red light and green light, which is the illuminated area. The second integrator optical system 19 and the superimposing lens 21 for yellow light make the illuminance distribution in the illuminated area uniform.

  Here, the dichroic mirror 6 is arranged on the optical path of the yellow light YL. The dichroic mirror 6 separates the yellow light YL emitted from the lighting device 2 into a red light LR and a green light LG. That is, the dichroic mirror 6 transmits the red light LR and reflects the green light LG to separate the yellow light YL.

  The second reflection mirror 7 is arranged on the optical path of the green light LG. The second reflection mirror 7 is arranged on the optical path of the green light LG separated by the dichroic mirror 6. The second reflection mirror 7 reflects the green light LG separated by the dichroic mirror 6 toward the light modulator 4G. After being reflected by the dichroic mirror 6 and the second reflection mirror 7, the green light LG passes through a field lens 9G to illuminate the image forming area of the light modulator 4G for green light.

  The third reflection mirror 8 is arranged on the optical path of the red light LR. The third reflecting mirror 8 reflects the red light LR separated by the dichroic mirror 6 toward the light modulator 4R. The red light LR passes through the dichroic mirror 6, passes through the third reflection mirror 8 and the field lens 9R, and illuminates the image forming area of the light modulator 4R for red light.

  The light modulator 4R modulates the red light LR according to image information while passing the red light LR, and forms image light corresponding to the red light LR. The light modulator 4G modulates the green light LG according to image information while passing the green light LG, and forms image light corresponding to the green light LG. The light modulator 4B modulates the blue light LB according to image information while passing the blue light LB, and forms image light corresponding to the blue light LB.

  For the light modulators 4R, 4G, 4B, for example, transmissive liquid crystal panels are used. A pair of polarizing plates (not shown) are arranged on the incident side and the outgoing side of the liquid crystal panel. A field lens 9R, a field lens 9G, and a field lens 9B are arranged on the incident side of the light modulator 4R, the light modulator 4G, and the light modulator 4B, respectively.

  The combining optical system 10 combines the respective image lights corresponding to the red light LR, the green light LG, and the blue light LB, and emits the combined image light toward the projection optical system 3. For the combining optical system 10, for example, a cross dichroic prism is used.

  The projection optical system 3 includes a plurality of projection lenses. The projection optical system 3 enlarges and projects the image light combined by the combining optical system 10 toward the screen SCR. Thus, an enlarged color image is displayed on the screen SCR.

<Light source device>
The configurations of the light source device and the cooling device according to the present embodiment will be described with reference to FIGS. 2, 3, 4, and 5. FIG. FIG. 2 is a perspective view showing the appearance of the light source device. FIG. 3 is a perspective view showing the appearance of the cooling device. FIG. 4 is an exploded perspective view showing the configuration of the cooling device. FIG. 5 is a cross-sectional view showing the fitted state of the heat receiving plate and the heat diffusion member along the plane M of FIG. Here, the illustration of the cooling fan 49 is omitted in FIGS. 2 to 5. In FIG. 2, illustration of wirings connected to the light source device 11 and the collimator lens 42 is omitted. Also, in FIG. 3, the plane M is a plane parallel to the YZ plane, and the broken arrows indicate the direction of the line of sight in FIG. 5 (cross-sectional view). Further, FIG. 4 also illustrates the light source unit 41 with respect to the cooling device 43.

  As shown in FIG. 2, the light source device 11 includes a light source unit 41 having a plurality of light emitting elements (not shown) and a cooling device 43. The cooling device 43 has a heat receiving plate 43a, a heat diffusion member 43b, and a heat sink 43c that is in contact with the heat diffusion member 43b.

  The heat receiving plate 43a is a substantially rectangular flat plate including a first side 43a1 and a second side 43a2, and has a protrusion 431 that is in contact with the light source unit 41. The heat receiving plate 43a may be a fixing member for fixing the light source device 11 to the projector 1 (see FIG. 1). That is, the light source device 11 may be attached to a frame or the like of the projector 1 using the heat receiving plate 43a. The material for forming the heat receiving plate 43a is not particularly limited, but an aluminum alloy is used in the present embodiment.

  In the light source unit 41, a plurality of light emitting elements are arranged in a matrix on a surface facing the light beam K emitting direction. The number of light emitting elements in the light source unit 41 is not particularly limited, but is, for example, 60. Further, the light source unit 41 may include a circuit board (not shown) for controlling light emission of the light emitting element and the like.

  The protruding portion 431 has a substantially rectangular columnar shape when viewed from the positive Z direction side, and is elongated in a direction along the first side portion 43a1 of the heat receiving plate 43a. A plurality of protrusions 431 are arranged in a direction along the second side 43a2 of the heat receiving plate 43a.

  Here, in the present specification, the direction in which the light beam K is emitted from the light source unit 41 is defined as a positive Z direction, the direction orthogonal to the Z direction, the direction along the first side 43a1 is defined as a Y direction, and the Y direction is defined. A direction perpendicular to the Z direction and along the second side 43a2 is defined as an X direction.

  The light source unit 41, the heat receiving plate 43a, the heat diffusion member 43b, and the heat sink 43c are arranged in this order in the Z direction. That is, the light source unit 41 is connected to the heat sink 43c via the heat receiving plate 43a and the heat diffusion member 43b. Therefore, heat generated from the plurality of light emitting elements of the light source unit 41 is transmitted from the plurality of protrusions 431 to the heat receiving plate 43a, and further transmitted from the heat receiving plate 43a to the heat sink 43c via the heat diffusion member 43b.

  Note that heat conductive grease may be applied between the light source unit 41 and the protrusion 431 to improve the adhesion between the light source unit 41 and the protrusion 431. Even when the heat conductive grease is used, the light source unit 41 and the heat receiving plate 43a are separated from each other in the area other than the protrusion 431, so that the light source unit 41 and the heat receiving plate 43a can be easily disassembled.

  As shown in FIG. 3, the heat sink 43c is connected to the heat receiving plate 43a via the heat diffusion member 43b. The heat sink 43c has a plurality of fins 44. The fins 44 are substantially pentagonal flat plates with one corner of a rectangle. The fins 44 are arranged such that long sides of the rectangle extend in the Y direction and short sides of the rectangle extend in the Z direction. Examples of a material for forming the fins 44 include a metal having thermal conductivity. In the present embodiment, an aluminum alloy is used as a material for forming the fins 44. The plurality of fins 44 are arranged in the X direction and substantially parallel to each other. Therefore, in the heat sink 43c, the Y direction and the negative Z direction are open. In other words, the air flow can pass through the gap between the plurality of fins 44 arranged in the X direction. The number, shape, and material of the fins 44 are not limited to the above. Further, the heat sink 43c is not limited to having the fins 44, and may have surface irregularities or needle-like projections instead of the fins 44.

  The cooling device 43 includes a cooling fan 49 (see FIG. 1) for cooling the heat sink 43c. The cooling fan 49 includes a blowing fan and a suction fan. With respect to the heat sink 43c, a blower fan is arranged on the positive Y direction side, and a suction fan is arranged on the negative Y direction side. Therefore, the airflow sent from the blower fan flows in the negative Y direction, passes through the gaps between the plurality of fins 44, is sucked by the suction fan, and is discharged out of the cooling device 43. Thereby, the heat conducted from the light source unit 41 (see FIG. 2) to the heat sink 43c is transferred to the airflow, and the cooling of the heat sink 43c is promoted.

  Here, the cooling device 43 is configured to include the blower fan and the suction fan as the cooling fan 49, but is not limited thereto. The cooling fan 49 may be either a blower fan or a suction fan. When the heat radiation performance of the heat sink 43c is sufficient, the cooling fan 49 may be omitted.

  As shown in FIG. 4, the heat receiving plate 43a has a plurality of recesses 432 on a surface (back surface) opposite to a surface (front surface) on which the protrusions 431 (see FIG. 2) are provided. The concave portion 432 is formed in an elongated groove shape along the X direction so as to fit with a convex portion of the heat diffusion member 43b described later. Eight concave portions 432 are arranged in the Y direction corresponding to the number of the convex portions. The plurality of recesses 432 are provided at positions facing the protrusions 431 provided on the surface of the heat receiving plate 43a.

  Here, the light source unit 41 and the heat receiving plate 43a may be fastened using screws. In that case, a screw hole can be provided in the protrusion 431. Thus, the arrangement of the concave portion 432 on the back surface of the heat receiving plate 43a and the thickness of the heat receiving plate 43a are not affected by the position and depth of the screw hole. In other words, if the fastening by screws is employed without providing the protrusion 431, the arrangement and shape of the recess 432, the thickness of the heat receiving plate 43a, and the like are easily affected. If the arrangement and the shape of the concave portion 432 are restricted, the shape of the heat sink 43c described later may be affected.

  The heat diffusion member 43b has a plurality of heat pipes 433a, 433b, 433c, 433d, 433e, 433f, 433g, and 433h (hereinafter, also simply referred to as "heat pipes 433") as projections fitted into the depressions 432. are doing. The heat pipe 433 is elongated in the X direction, and the length in the X direction other than the heat pipe 433a is substantially equal to the length of the second side 43a2 of the heat receiving plate 43a. The length of the heat pipe 433a in the X direction is shorter than the length of the second side 43a2.

  As shown in FIG. 5, the heat pipe 433 has a thickness in the Z direction, and the thickness is fitted in the concave portion 432 as a convex portion of the heat diffusion member 43b. Then, the eight heat pipes 433 are fitted in the eight recesses 432 and arranged side by side in the Y direction. Thereby, the heat receiving plate 43a and the heat diffusion member 43b are fitted. The heat pipe 433 has a surface that fits into the concave portion 432 and a surface that faces the Z direction in contact with the heat sink 43c.

  The heat pipe 433 is made of a forming material such as copper, for example, and contains a working fluid in an internal space. The heat pipe 433 has a function of moving and diffusing heat in the internal space by repeating evaporation (vaporization) of the working fluid, movement of gas, and aggregation (liquefaction) of gas. Thus, the heat pipe 433 conducts the heat conducted from the heat receiving plate 43a to the heat sink 43c while diffusing the heat.

  Returning to FIG. 4, the heat pipes 433e, 433f, 433g, and 433h are provided with extensions 434e, 434f, 434g, and 434h, respectively (hereinafter, also simply referred to as "extensions 434"). The internal space of the heat pipe 433 extends inside the extension part 434. Therefore, the heat pipes 433e, 433f, 433g, and 433h have a longer internal space in the X direction than the other heat pipes 433a and 433b.

  The extension portions 434e and 434g are bent from the positive X-direction end portions of the heat pipes 433e and 433g, respectively, are raised to the negative Z-direction side, and then are bent to the negative X-direction side to form the heat sink 43c. It extends to the end on the negative X direction side. Therefore, the heat pipes 433e and 433g are formed in a “U” shape when viewed from the Y direction side.

  The extension portions 434f and 434h are bent from the negative X-direction side ends of the heat pipes 433f and 433h, respectively, and are raised to the negative Z-direction side, and then bent to the positive X-direction side to form the heat sink 43c. It extends to the end on the positive X direction side. Therefore, the heat pipes 433f and 433h are formed in a “U” shape when viewed from the Y direction side.

  The fin 44 of the heat sink 43c is provided with a notch 45 so that the extension 434 does not interfere. That is, the extension portion 434 is provided so as to bite into the fin 44 side. Thereby, the extension part 434 is arranged at a position where the air flow of the cooling fan easily hits. Therefore, in the heat pipes 433e, 433f, 433g, and 433h, the heat dissipation performance is improved in addition to the heat diffusion function.

  In the present embodiment, a blower fan (not shown) is arranged on the positive Y direction side of the heat sink 43c. Therefore, of the heat pipes 433 arranged in the Y direction, the extension portions 434 are provided in the heat pipes 433e, 433f, 433g, and 433h far from the blower fan. Therefore, cooling performance can be ensured also in the heat pipes 433e to 433h. In addition, since the variation in the cooling performance among the plurality of heat pipes 433 is suppressed, the unevenness in the cooling performance with respect to the plurality of light emitting elements of the light source unit 41 can be reduced.

  As for the configuration of the heat pipe 433, such as the type of hydraulic fluid and the arrangement of the internal space, a known technique can be employed. The shape, arrangement, number, and the like of the heat pipe 433 and the extension 434 are not limited to the above-described embodiments.

  As described above, according to the projector 1 and the light source device 11 according to the present embodiment, the following effects can be obtained.

  The cooling performance of the light source device 11 can be improved as compared with the related art. Specifically, since the concave portion 432 of the heat receiving plate 43a and the heat pipe 433 as the convex portion of the heat diffusing member 43b are fitted, the contact area between the heat receiving plate 43a and the heat diffusing member 43b increases. Therefore, the heat of the light source unit 41 is easily transmitted to the heat diffusion member 43b via the heat receiving plate 43a, and further transmitted from the heat diffusion member 43b to the heat sink 43c and released to the outside. Thus, even when the number of light emitting elements in the light source unit 41 is increased, the cooling performance of the cooling device 43 can be ensured. That is, the light source device 11 including the cooling device 43 with improved cooling performance can be provided.

  Since the recess 432 is provided at a position facing the protrusion 431, the distance between the protrusion 431 and the recess 432 is smaller than when the recess 432 is not provided at a position facing the protrusion 431. . Therefore, the heat of the light source unit 41 is easily transmitted from the protrusion 431 to the heat diffusion member 43b via the recess 432, and the cooling performance of the cooling device 43 can be further improved.

  Since the heat sink 43c has the fins 44, the heat conducted from the light source unit 41 to the heat sink 43c is also released from the fins 44. Therefore, the cooling performance of the cooling device 43 can be further improved.

  The heat conducted from the light source unit 41 to the heat diffusion member 43b is further diffused by the heat pipe 433 and conducted to the heat sink 43c. Therefore, heat conduction between the heat receiving plate 43a and the heat sink 43c is promoted, and uneven distribution of heat in the heat sink 43c can be reduced. Thereby, in the cooling device 43, the cooling performance can be further improved. Further, since the fins 44 are made of an aluminum alloy, the heat sink 43c can be easily reduced in weight, for example, as compared with the case where the fins 44 are made of copper.

  Since the cooling fan 49 that cools the heat sink 43c is provided, heat radiation from the heat sink 43c is promoted by the cooling fan 49. Therefore, the cooling performance of the cooling device 43 can be further improved.

  Since the projector 1 includes the light source device 11, the cooling performance of the cooling device 43 is improved, and even if the number of light emitting elements is increased, overheating of the light emitting elements can be suppressed. Therefore, it is possible to provide the projector 1 in which a decrease in the light output and the life of the light emitting element is suppressed, and the quality is improved.

(Embodiment 2)
<Light source device>
The configuration of the light source device according to the present embodiment will be described with reference to FIGS. FIG. 6 is a perspective view illustrating an appearance of the light source device according to the second embodiment. FIG. 7 is a perspective view showing the appearance of the cooling device. Here, the illustration of the cooling fan 49 is omitted in FIGS. 6 and 7. In FIG. 6, the wirings connected to the light source device and the collimator lens 42 are not shown. The plane N in FIG. 7 is a plane parallel to the YZ plane.

  The cooling device 53 of the present embodiment is different from the cooling device 43 of the first embodiment in the configuration of the heat receiving plate and the heat diffusion member. Therefore, the same components as those of the first embodiment are denoted by the same reference numerals, and duplicate description will be omitted.

  As shown in FIG. 6, the light source device 111 of the present embodiment includes a light source unit 41 having a plurality of light emitting elements (not shown) and a cooling device 53. The cooling device 53 has a heat receiving plate 53a, a heat diffusion member 53b, and a heat sink 53c in contact with the heat diffusion member 53b.

  The heat receiving plate 53a is a substantially rectangular flat plate including a first side 53a1 and a second side 53a2, and has a protrusion 531 that is in contact with the light source unit 41. The heat receiving plate 53a may be a fixing member for fixing the light source device 111 to the projector 1 (see FIG. 1). That is, the light source device 111 may be attached to a frame or the like of the projector 1 using the heat receiving plate 53a. The material for forming the heat receiving plate 53a is not particularly limited, but an aluminum alloy is used in the present embodiment.

  The projecting portion 531 has a substantially rectangular columnar shape when viewed from the positive Z direction side, and is formed to be elongated in the direction (Y direction) along the first side portion 53a1 of the heat receiving plate 53a. A plurality of protrusions 531 are arranged in a direction (X direction) along the second side 53a2 of the heat receiving plate 53a.

  The light source unit 41, the heat receiving plate 53a, the heat diffusion member 53b, and the heat sink 53c are arranged in this order in the Z direction. That is, the light source unit 41 is connected to the heat sink 53c via the heat receiving plate 53a and the heat diffusion member 53b. Therefore, heat generated from the plurality of light emitting elements of the light source unit 41 is transmitted from the plurality of protrusions 531 to the heat receiving plate 53a, and further transmitted from the heat receiving plate 53a to the heat sink 53c via the heat diffusion member 53b.

  Note that heat conductive grease may be applied between the light source unit 41 and the protrusion 531 to improve the adhesion between the light source unit 41 and the protrusion 531. Even in the case where the heat conductive grease is used, the light source unit 41 and the heat receiving plate 53a are separated from each other in a region other than the protrusion 531. Therefore, the light source unit 41 and the heat receiving plate 53a can be easily disassembled.

  As shown in FIG. 7, the heat sink 53c is connected to the heat receiving plate 53a via the heat diffusion member 53b. The heat sink 53c has a plurality of fins 54. The fin 54 is a rectangular flat plate made of copper. The fins 54 are arranged such that the long sides of the rectangle extend in the Y direction and the short sides of the rectangle extend in the Z direction. The plurality of fins 54 are arranged in the X direction and substantially parallel to each other. Therefore, in the heat sink 53c, the Y direction and the negative Z direction are open. In other words, the airflow can pass through the gap between the plurality of fins 54 arranged in the X direction. The number, shape, and material of the fins 54 are not limited to the above. Further, the heat sink 53c is not limited to having the fins 54, and may have surface irregularities or needle-like projections instead of the fins 54.

  The cooling device 53 includes a cooling fan 49 (see FIG. 1) for cooling the heat sink 53c. The cooling fan 49 includes a blowing fan and a suction fan. With respect to the heat sink 53c, a blower fan is arranged on the positive Y direction side, and a suction fan is arranged on the negative Y direction side. Therefore, the airflow sent from the blower fan flows in the negative Y direction, passes through the gaps between the plurality of fins 54, is sucked by the suction fan, and is discharged out of the cooling device 53. Thereby, the heat conducted from the light source unit 41 (see FIG. 6) to the heat sink 53c is transferred to the airflow, and the cooling of the heat sink 53c is promoted.

  Here, the cooling device 53 is configured to include the blower fan and the suction fan as the cooling fan 49, but is not limited thereto. The cooling fan 49 may be either a blower fan or a suction fan. When the heat radiation performance of the heat sink 53c is sufficient, the cooling fan 49 may be omitted.

  Next, the configuration of the cooling device 53 will be described with reference to FIGS. 8, 9, and 10. FIG. 8 and 9 are exploded perspective views showing the configuration of the cooling device. FIG. 10 is a cross-sectional view showing the fitted state of the heat receiving plate and the heat diffusion member along the surface N of FIG. FIG. 10 shows a cross section as viewed from the direction of the dashed arrow in FIG.

  As shown in FIGS. 8 and 9, the heat receiving plate 53a has one concave portion 532 on the surface (back surface) opposite to the surface (front surface) on which the protrusion 531 is provided. The heat diffusion member 53b has a protrusion 533. The concave portion 532 has a rectangular planar shape from the negative Z direction side so as to fit with the convex portion 533. The recess 532 is provided at a position facing the protrusion 531 provided on the surface of the heat receiving plate 53a.

  Here, the light source unit 41 and the heat receiving plate 53a may be fastened using screws. In this case, a screw hole can be provided in the projection 531. Thus, the arrangement of the concave portion 532 on the back surface of the heat receiving plate 53a and the thickness of the heat receiving plate 53a are not affected by the position and the depth of the screw hole. In other words, if the fastening by screws is employed without providing the projection 531, the arrangement and shape of the recess 532, the thickness of the heat receiving plate 53 a, and the like are easily affected. If the arrangement and the shape of the concave portion 532 are restricted, the shape of the heat sink 53c described later may be affected.

  The heat diffusion member 53b has a vapor chamber (not shown) inside. That is, the heat diffusion member 53b of the cooling device 53 is different from the heat diffusion member 43b (cooling device 43) in the first embodiment in that a heat pipe is provided instead of a heat pipe.

  As shown in FIG. 10, the convex portion 533 of the heat diffusion member 53b is fitted in the concave portion 532 of the heat receiving plate 53a. Thereby, the heat receiving plate 43a and the heat diffusion member 43b are fitted. The surface of the heat diffusion member 53b that fits into the concave portion 532 (the surface on which the convex portion 533 is provided) and the surface that faces in the Z direction are in contact with the heat sink 53c.

  The vapor chamber is made of a forming material such as copper, for example, and contains a working fluid in an internal space. The vapor chamber has a function of transferring and diffusing heat by repeatedly evaporating (vaporizing), moving a gas, and coagulating (liquefying) a gas in an internal space. Thus, the vapor chamber conducts the heat conducted from the heat receiving plate 53a to the heat sink 53c while diffusing the heat. In addition, as for the configuration such as the type of the working fluid of the vapor chamber and the arrangement of the internal space, a known technique can be adopted. Further, the shape, arrangement, number, and the like of the concave portions 532 and the convex portions 533 are not limited to the above-described embodiments.

  As described above, according to the light source device 111 of the present embodiment, the following effects can be obtained in addition to the effects of the first embodiment.

  The heat conducted from the light source unit 41 to the heat diffusion member 53b is further diffused by the vapor chamber and conducted to the heat sink 53c. Therefore, conduction of heat between the heat receiving plate 53a and the heat sink 53c is promoted, and uneven distribution of heat in the heat sink 53c can be reduced. Thereby, in the cooling device 53 of the light source device 111, the cooling performance can be further improved. Further, since the fins 54 are made of copper, the thermal conductivity is further improved, for example, as compared with the case where the fins are formed of an aluminum alloy. Therefore, the cooling performance of the cooling device 53 can be further improved.

  Since the number of the convex portions 533 and the number of the concave portions 532 are one each, the number of steps required for forming the convex portions 533 and the concave portions 532 in the manufacturing process of the cooling device 53 can be reduced.

  The contents derived from the embodiment will be described below.

  The light source device has a heat receiving plate having a light source unit having a plurality of light emitting elements, a projection in contact with the light source unit, and a recess provided on a surface facing the surface on which the projection is provided, and fitted with the recess. The light source unit is connected to the heat sink via the heat receiving plate and the heat diffusion member.

  According to this configuration, the cooling performance can be improved as compared with the related art. Specifically, since the concave portion of the heat receiving plate and the convex portion of the heat diffusing member are fitted, the contact area between the heat receiving plate and the heat diffusing member increases. Therefore, the heat of the light source unit is easily transmitted to the heat diffusion member via the heat receiving plate, and further transmitted from the heat diffusion member to the heat sink and released to the outside. Thereby, even when the number of light emitting elements is increased, the cooling performance of the cooling device can be ensured. That is, it is possible to provide a light source device including a cooling device with improved cooling performance.

  In the light source device described above, it is preferable that the recess is provided at a position facing the protrusion.

  According to this configuration, the distance between the protrusion and the recess is smaller than when the recess is not provided at a position facing the protrusion. Therefore, the heat of the light source unit is easily transmitted from the protrusion to the heat diffusion member via the recess, and the cooling performance of the cooling device can be further improved.

  In the above light source device, the heat sink preferably has a fin.

  According to this configuration, the heat conducted from the light source unit to the heat sink is also released from the fin. Therefore, the cooling performance of the cooling device can be further improved.

  In the above light source device, it is preferable that the heat diffusion member has a heat pipe and the fin is made of an aluminum alloy.

  According to this configuration, the heat conducted from the light source unit to the heat diffusion member is further diffused by the heat pipe and conducted to the heat sink. Therefore, heat conduction between the heat receiving plate and the heat sink is promoted, and uneven distribution of heat in the heat sink can be reduced. Thereby, in the cooling device, the cooling performance can be further improved. In addition, since the fins are made of an aluminum alloy, the heat sink can be more easily reduced in weight than, for example, when the fins are made of copper.

  In the above light source device, the heat diffusion member preferably has a vapor chamber, and the fins are preferably made of copper.

  According to this configuration, the heat conducted from the light source unit to the heat diffusion member is further diffused by the vapor chamber and conducted to the heat sink. Therefore, heat conduction between the heat receiving plate and the heat sink is promoted, and uneven distribution of heat in the heat sink can be reduced. Thereby, in the cooling device, the cooling performance can be further improved. Further, since the fins are made of copper, the thermal conductivity is further improved, for example, as compared with the case where the fins are formed of an aluminum alloy. Therefore, the cooling performance of the cooling device can be further improved.

  It is preferable that the light source device includes a cooling fan that cools the heat sink.

  According to this configuration, heat radiation from the heat sink is promoted by the cooling fan. Therefore, the cooling performance of the cooling device can be further improved.

  The projector includes the above light source device.

  According to this configuration, since the cooling performance of the cooling device is improved, overheating of the light emitting element is suppressed. Therefore, even if the number of light emitting elements is increased, a decrease in light output and life of the light emitting elements is suppressed, and a projector with improved quality can be provided.

  DESCRIPTION OF SYMBOLS 1 ... Projector, 11 and 111 ... Light source device, 41 ... Light source unit, 43a, 53a ... Heat receiving plate, 43b, 53b ... Heat diffusion member, 43c, 53c ... Heat sink, 44, 54 ... Fin, 49 ... Cooling fan, 431 531: Projection, 432, 532: Concave, 433, 433a, 433b, 433c, 433d, 433e, 433f, 433g, 433h: Heat pipe as a convex, 533: Convex.

Claims (7)

A light source unit having a plurality of light emitting elements,
A heat receiving plate having a projection in contact with the light source unit, and a recess provided on a surface facing the surface on which the projection is provided,
A heat diffusion member having a convex portion fitted with the concave portion,
A heat sink in contact with the heat diffusion member,
The light source unit is connected to the heat sink via the heat receiving plate and the heat diffusion member.   The light source device according to claim 1, wherein the recess is provided at a position facing the protrusion.   The light source device according to claim 1, wherein the heat sink has a fin. The heat diffusion member has a heat pipe,
The light source device according to claim 3, wherein the fin is made of an aluminum alloy. The heat diffusion member has a vapor chamber,
The light source device according to claim 3, wherein the fin is made of copper.   The light source device according to any one of claims 1 to 5, further comprising a cooling fan that cools the heat sink.   A projector comprising the light source device according to any one of claims 1 to 6.

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