JP2009065072A - Light source device, manufacturing method of light source device, lighting system, monitor device, and image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light source device capable of reducing variation of a rotating angle of an external resonator, and of continuing emission of laser light with high efficiency; a manufacturing method of the light source device; a lighting system using the light source device; a monitor device; and an image display device. <P>SOLUTION: This light source device includes: a light source part emitting light; a volume hologram 18 being the external resonator resonating light emitted by the light source part; and a first fixing member 21 and a second fixing member 22 being external resonator fixing parts having a first adjustment shaft for adjusting a first axis rotation angle of the external resonator centering around a first axis, and a second adjustment shaft for adjusting a second axis rotation angle of the external resonator centering around a second axis nearly orthogonal to the first axis, and fixing the external resonator with the first axis rotation angle and the second axis rotation angle adjusted. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a light source device, a method for manufacturing the light source device, an illumination device, a monitor device, and an image display device, and more particularly, to a technology of a light source device having an external resonator.

  In recent years, a technique using a laser light source has been proposed as a light source device of an image display device. Laser light sources have been developed as light sources for image display devices with higher output and more colors. Compared with a UHP lamp conventionally used as a light source, a laser light source has advantages such as high color reproducibility, instant lighting, and long life. By using an external resonator that resonates the light, the laser light source can narrow the wavelength of the laser light and increase the output of the laser light. A technique of a light source device having an external resonator is proposed in Patent Document 1, for example. In the technique of Patent Document 1, a narrow band reflection filter is used as an external resonator.

JP-A-11-177178

  In general, the external resonator is fixed to the substrate using an adhesive member. By accurately adjusting the rotation angle of the external resonator so that the reflection structure of the external resonator is orthogonal to the light beam, light can be resonated between the mirror layer of the semiconductor element and the external resonator. When the external resonator is fixed using an adhesive, the rotation angle of the external resonator is adjusted by changing the thickness of the adhesive layer that is the adhesive layer. When the thickness of the adhesive layer is different, the amount of expansion / contraction of the adhesive layer due to temperature change is also different. If the amount of expansion / contraction of the adhesive layer varies from part to part, the rotation angle of the external resonator changes, so that the efficiency of laser oscillation is reduced. As described above, according to the conventional technique, there is a problem that the rotation angle of the external resonator changes and the laser oscillation efficiency may be lowered. The present invention has been made in view of the above-described problems, and can reduce a change in the rotation angle of the external resonator and can continuously emit laser light with high efficiency, a method of manufacturing the light source device, An object is to provide an illumination device, a monitor device, and an image display device using the light source device.

  In order to solve the above-described problems and achieve the object, a light source device according to the present invention is centered on a light source unit that emits light, an external resonator that resonates light emitted by the light source unit, and a first axis. The first adjustment axis for adjusting the first axis rotation angle of the external resonator and the second axis rotation angle of the external resonator around the second axis, which is an axis substantially orthogonal to the first axis, are adjusted. And an external resonator fixing portion that fixes the external resonator in a state where the first axis rotation angle and the second axis rotation angle are adjusted.

  In the manufacturing process of the light source device, the first axis of rotation and the second axis of rotation of the external resonator can be adjusted by using the first adjustment axis and the second adjustment axis. By using the external resonator fixing portion including the first adjustment shaft and the second adjustment shaft, it is not necessary to adjust the rotation angle of the external resonator by changing the thickness of the adhesive layer. For this reason, the change of the rotation angle of the external resonator due to the temperature change can be reduced. By reducing the change in the rotation angle of the external resonator, laser oscillation with high efficiency can be continued. As a result, a change in the rotation angle of the external resonator can be reduced, and a light source device capable of continuously emitting laser light with high efficiency can be obtained.

  Moreover, as a preferable aspect of the present invention, the external resonator fixing unit includes a base material on which a light source unit is disposed, and the external resonator fixing unit has a first axis rotation angle adjusted with respect to the base material by a first adjustment shaft. It is desirable to have a fixing member and a second fixing member whose second axis rotation angle is adjusted with respect to the first fixing member by the second adjustment shaft. Thereby, the first axis rotation angle and the second axis rotation angle of the external resonator can be adjusted.

  Moreover, as a preferable aspect of the present invention, it is desirable to have at least one of a first bearing portion that supports the first adjustment shaft and a second bearing portion that supports the second adjustment shaft. By using a 1st bearing part, the 1st axis | shaft rotation angle of a 1st fixing member can be adjusted with respect to a base material. By using the second bearing portion, the second shaft rotation angle of the second fixing member can be adjusted with respect to the first fixing member.

  Moreover, as a preferable aspect of the present invention, a first fixing surface that is provided on the base and fixes the first fixing member, a second fixing surface that is provided on the first fixing member and fixes the second fixing member, It is desirable to have at least one of a third fixing surface provided on the second fixing member and fixing the external resonator. Thereby, the rotational deviation of the external resonator can be reduced.

  Moreover, as a preferable aspect of the present invention, a first adhesive member that bonds the first fixing member to the first fixing surface, a second adhesive member that bonds the second fixing member to the second fixing surface, and a third fixing surface It is desirable to have at least one of a third adhesive member for adhering the external resonator to the first adhesive member. By using the first adhesive member, the first fixing member can be fixed to the first fixing surface. By using the second adhesive member, the second fixing member can be fixed to the second fixing surface. By using the third adhesive member, the external resonator can be fixed to the third fixing surface.

  Moreover, as a preferable aspect of the present invention, the first fixing member includes a first fixing member penetrating a surface facing the first fixing surface and a surface opposite to the surface facing the first fixing surface. It is desirable to have at least one of 1 through-hole and the 2nd through-hole which penetrates the surface on the opposite side to the 2nd fixed surface and 2nd fixed surface among 1st fixing members. By injecting the adhesive from the first through hole, the first fixing member can be firmly fixed to the first fixing surface. By injecting the adhesive from the second through hole, the second fixing member can be firmly fixed to the second fixing surface.

  Moreover, as a preferable aspect of the present invention, at least one of a first screw portion that fixes the first fixing member to the first fixing surface and a second screw portion that fixes the second fixing member to the second fixing surface. It is desirable to have one. By using the first screw portion, it is possible to suppress peeling of the first fixing member from the first fixing surface. By using the second screw portion, peeling of the second fixing member from the second fixing surface can be suppressed. Thereby, the light source device can ensure high reliability. By using the first screw portion and the second screw portion, the time required for fixing can be shortened as compared with the case where an adhesive is used.

  As a preferred aspect of the present invention, it is desirable that the second fixing member has a first structure and a second structure, and the first structure and the second structure sandwich an external resonator. Thereby, an external resonator can be arrange | positioned in the position close | similar to a 1st fixing member, and a light source device can be reduced in size.

  Moreover, as a preferable aspect of the present invention, it is desirable that the second fixing surface is any one of a surface facing the first structure and a surface facing the second structure in the first fixing member. When the external resonator thermally expands, the external resonator can be extended to the opposite side of the first structure and the second structure to the side on which the second fixing surface is provided. By freely extending the external resonator, the generation of stress in the external resonator can be reduced. By making it possible to reduce the distortion of the external resonator, changes in the wavelength characteristics of the external resonator and a decrease in reflectance can be reduced.

  Moreover, as a preferable aspect of the present invention, it is desirable that both the first axis and the second axis are substantially orthogonal to a light beam incident on the external resonator from the light source unit. As a result, adjustment to enable laser oscillation with high efficiency can be performed.

  Moreover, as a preferable aspect of the present invention, it is desirable that the external resonator has a volume hologram that diffracts light from the light source unit. By using the volume hologram, it is possible to narrow the band of the laser light in the external resonator.

  Furthermore, the manufacturing method of the light source device according to the present invention is a manufacturing method of a light source device having an external resonator that resonates light from the light source unit, and is centered on the first axis using the first adjustment axis. The first axis rotation angle adjusting step for adjusting the first axis rotation angle of the external resonator and the second adjustment axis are used to adjust the external resonator around the second axis that is an axis substantially orthogonal to the first axis. A second axis rotation angle adjusting step for adjusting the second axis rotation angle, and an external resonator fixing step for fixing the external resonator in a state where the first axis rotation angle and the second axis rotation angle are adjusted. It is characterized by. Thereby, the change of the rotation angle of the external resonator can be reduced, and the laser beam can be emitted with high efficiency.

  Furthermore, an illumination device according to the present invention includes the light source device described above, and illuminates an object to be irradiated using light from the light source device. By using the above light source device, laser light can be emitted with high efficiency. Thereby, the illuminating device which can illuminate a to-be-irradiated object with high efficiency can be obtained.

  Furthermore, a monitor device according to the present invention includes the above-described illumination device and an imaging unit that captures an image of a subject illuminated by the illumination device. By using the illumination device described above, the object can be illuminated with high efficiency. Thereby, a monitor device capable of monitoring a bright image using light supplied with high efficiency can be obtained.

  Furthermore, an image display device according to the present invention includes the light source device described above, and displays an image using light from the light source device. By using the above light source device, laser light can be emitted with high efficiency. Thereby, an image display apparatus capable of displaying a bright image using light supplied with high efficiency can be obtained.

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

  FIG. 1 shows a perspective configuration of a light source device 10 according to Embodiment 1 of the present invention. FIG. 2 shows a configuration in which the optical prism 14 is removed from the light source device 10. The optical prism 14, the second-harmonic generation (SHG) element 16, and the volume hologram 18 are arranged in parallel in the Z-axis direction. The Y axis is a first axis that is an axis perpendicular to the Z axis. The X axis is a second axis that is an axis perpendicular to the Z axis and the Y axis. The semiconductor element 11 is a light source unit that emits a plurality of fundamental wave lights. The semiconductor element 11 is, for example, a surface emitting array light source. The fundamental light is, for example, infrared light. The first wavelength is, for example, 1064 nm. The semiconductor element 11 is mounted on the submount 12. The submount 12 is a heat dissipation board that dissipates heat generated in the semiconductor element 11.

  The optical prism 14 is provided at a position where light from the semiconductor element 11 enters. The optical prism 14 is disposed on two prism support portions 13 provided with the semiconductor element 11 interposed therebetween. The optical prism 14 has a right triangular side surface. The optical prism 14 is configured by bonding two triangular prisms that bisect the right triangle. A dichroic film 15 is sandwiched between the two triangular prisms. The dichroic film 15 transmits light having a first wavelength and reflects light having a second wavelength that is different from the first wavelength.

  The SHG element 16 is disposed on the SHG element support portion 17. The SHG element 16 is a wavelength conversion element that converts the wavelength of the fundamental wave light of the first wavelength from the semiconductor element 11 and emits the harmonic light of the second wavelength. The harmonic light is, for example, visible light. The second wavelength is half the first wavelength and is, for example, 532 nm. The SHG element 16 has a rectangular parallelepiped shape.

As the SHG element 16, for example, a nonlinear optical crystal can be used. As the nonlinear optical crystal, for example, a polarization inversion crystal (Periodically Poled Lithium Niobate; PPLN) of lithium niobate (LiNbO ₃ ) can be used. The SHG element 16 has a polarization inversion structure with a pitch corresponding to the first wavelength of the fundamental light. By using the SHG element 16, it is possible to supply a laser beam having a desired wavelength and a sufficient amount of light using a general-purpose light source that can be easily obtained.

The volume hologram 18 is an external resonator that resonates light from the semiconductor element 11 with the semiconductor element 11. The volume hologram 18 selectively reflects light having the first wavelength and transmits light having a wavelength different from the first wavelength (including the second wavelength). As the volume hologram 18, for example, VHG (Volume Holographic Grating) can be used. VHG can be formed using a photorefractive crystal such as LiNbO ₃ or BGO, a polymer, or the like. In the volume hologram 18, interference fringes generated by incident light incident from two directions are recorded. The interference fringes are recorded as a periodic structure in which a high refractive index portion and a low refractive index portion are periodically arranged. The volume hologram 18 selectively reflects only light that satisfies interference fringes and Bragg conditions by diffraction. The volume hologram 18 is fitted into the second fixing member 22. A light beam incident on the volume hologram 18 from the semiconductor element 11 is substantially parallel to the Z axis. Both the Y-axis that is the first axis and the X-axis that is the second axis are substantially orthogonal to the light beam that enters the volume hologram 18 from the semiconductor element 11.

  The base material 20 is a plate-like member provided with a step portion 23. The step portion 23 is a portion formed so that the height in the Y-axis direction is lower than the portion of the base material 20 other than the step portion 23. A surface substantially parallel to the XZ plane of the step portion 23 is a first fixing surface 31 that fixes the first fixing member 21. The Y axis that is the first axis is substantially perpendicular to the first fixed surface 31. The semiconductor element 11, the prism support part 13, and the SHG element support part 17 are arranged in a part other than the step part 23 in the base material 20. The prism support portion 13 is a plate-like member that supports the optical prism 14 on the base material 20. The optical prism 14 is positioned by the prism support portion 13. The SHG element support portion 17 is a plate-like member that supports the SHG element 16 on the base material 20. The SHG element 16 is positioned by the SHG element support part 17.

  The first fixing member 21 is disposed on the first fixing surface 31 of the base material 20. The second fixing member 22 is disposed on the first fixing member 21. The second fixing member 22 has a cylindrical second convex portion 25. The first fixing member 21 and the second fixing member 22 are external resonator fixing portions that fix the volume hologram 18. The base material 20, the first fixing member 21, and the second fixing member 22 may be configured using any material, and may be configured using, for example, a metal material.

  FIG. 3 shows a YZ cross-sectional configuration of the light source device 10. The semiconductor element 11 emits a plurality of fundamental wave lights arranged in parallel in the X-axis direction in the Y-axis direction. Light from the semiconductor element 11 enters the optical prism 14. The light that has entered the optical prism 14 is reflected at the interface of the optical prism 14, and the optical path is bent in the Z-axis direction before entering the dichroic film 15. The fundamental wave light incident on the dichroic film 15 passes through the dichroic film 15 and then exits from the optical prism 14. The light from the optical prism 14 enters the SHG element 16.

  The harmonic light generated when the fundamental light is incident on the SHG element 16 from the optical prism 14 passes through the volume hologram 18. The harmonic light transmitted through the volume hologram 18 is emitted outside the light source device 10. The fundamental wave light transmitted from the optical prism 14 through the SHG element 16 is reflected by the volume hologram 18. The light reflected by the volume hologram 18 enters the SHG element 16.

  The harmonic light generated by the SHG element 16 by the incidence of the fundamental light from the volume hologram 18 is reflected by the dichroic film 15 in the optical prism 14, and the optical path is bent in the Y-axis direction. The light reflected by the dichroic film 15 is further bent in the Z-axis direction due to reflection at the interface of the optical prism 14, and is emitted from the optical prism 14. The light emitted from the optical prism 14 passes through the vicinity of the SHG element 16 and the vicinity of the volume hologram 18. The light that has passed through the vicinity of the SHG element 16 and the vicinity of the volume hologram 18 is emitted outside the light source device 10 in the same manner as the light that has passed through the volume hologram 18.

  The fundamental light that has passed through the SHG element 16 from the volume hologram 18 side passes through the dichroic film 15 in the optical prism 14. The light transmitted through the dichroic film 15 is reflected at the interface of the optical prism 14 and travels toward the semiconductor element 11. Light incident on the semiconductor element 11 from the optical prism 14 is reflected by a mirror layer (not shown) provided on the semiconductor element 11. The light reflected by the mirror layer of the semiconductor element 11 and the volume hologram 18 resonates with the fundamental wave light newly emitted from the semiconductor element 11 and is amplified. By using the optical prism 14, the harmonic light generated when the fundamental light is incident on the SHG element 16 from the volume hologram 18 travels outside the light source device 10, and the fundamental light transmitted through the SHG element 16 is transmitted to the semiconductor element 11. It can be advanced in the direction. Thereby, wavelength conversion efficiency can be improved. The light source unit is not limited to the semiconductor element 11 that emits a plurality of lights, and may be a semiconductor element that emits one light.

  FIG. 4 shows the base material 20, the first fixing member 21, the second fixing member 22, and the volume hologram 18 in a developed state. The first fixing member 21 has a shape in which one plate member substantially parallel to the XZ plane and two plate members substantially parallel to the YZ plane are combined. The 1st convex part 27 is provided in the bottom face 35 of the part formed substantially parallel to XZ surface among the 1st fixing members 21. As shown in FIG. The first convex portion 27 has a cylindrical shape. The 1st convex part 27 is formed substantially parallel to the Y-axis which is a 1st axis | shaft. The first convex portion 27 functions as a first adjustment axis for adjusting the first axis rotation angle of the volume hologram 18 around the first axis. The first axis rotation angle is a rotation angle about the first axis.

  Similar to the first fixing member 21, the second fixing member 22 has a shape in which one plate member substantially parallel to the XZ plane and two plate members substantially parallel to the YZ plane are combined. The two second convex portions 25 are respectively provided on the side surfaces 36 of the portion of the second fixing member 22 formed substantially parallel to the YZ plane. The two second convex portions 25 are formed substantially parallel to the X axis that is the second axis. The two second convex portions 25 function as second adjustment axes for adjusting the second axis rotation angle of the volume hologram 18 around the second axis. The second axis rotation angle is a rotation angle about the second axis.

  The first recess 26 is provided on the first fixed surface 31 of the substrate 20. The first concave portion 26 is a circular hole formed so that the first convex portion 27 of the first fixing member 21 can be inserted. The 1st recessed part 26 functions as a 1st bearing part which supports the 1st convex part 27 which is a 1st adjustment axis | shaft. The first fixing member 21 is installed on the base material 20 by inserting the first convex portion 27 into the first concave portion 26. The first fixing member 21 has a first axis rotation angle adjusted with respect to the base material 20 by the first convex portion 27.

  The two second recesses 28 are respectively provided at both ends of the first fixing member 21 substantially parallel to the XZ plane. The 2nd recessed part 28 is a hollow of the shape close | similar to the semicircle formed so that a part of 2nd convex part 25 of the 2nd fixing member 22 could be engage | inserted. The two second concave portions 28 function as second bearing portions that support and support the second convex portion 25 that is the second adjustment shaft. The second fixing member 22 is installed on the first fixing member 21 by placing the second convex portion 25 on the second concave portion 28. The second fixing member 22 has a second axis rotation angle adjusted with respect to the first fixing member 21 by the second convex portion 25.

  The first fixing surface 31 is formed substantially parallel to the bottom surface 35 of the first fixing member 21. Thereby, the space between the first fixed surface 31 and the bottom surface 35 can be made as narrow as possible. The second fixing surface 32 is a surface of the first fixing member 21 that is substantially parallel to the YZ plane and faces the second fixing member 22. The second fixing surface 32 fixes the second fixing member 22. The second fixing surface 32 is formed substantially parallel to the side surface 36 of the second fixing member 22. Thereby, the space between the second fixed surface 32 and the side surface 36 can be made as narrow as possible. The third fixing surface 33 is a surface of the second fixing member 22 that is substantially parallel to the YZ plane and faces the volume hologram 18. The third fixing surface 33 fixes the volume hologram 18. The third fixed surface 33 is formed substantially parallel to the incident surface of the volume hologram 18 where the light from the SHG element 16 is incident and the side surface 37 adjacent to the emission surface from which the harmonic light is emitted. Thereby, the space between the third fixing surface 33 and the side surface 37 can be made as narrow as possible.

  Next, a procedure until the volume hologram 18 is fixed in the manufacturing process of the light source device 10 will be described. First, the volume hologram 18 is temporarily installed by combining the base material 20, the first fixing member 21, the second fixing member 22, and the volume hologram 18. The positioning of the volume hologram 18 in the X-axis direction, the Y-axis direction, and the Z-axis direction is performed by combining the base material 20, the first fixing member 21, the second fixing member 22, and the volume hologram 18.

  After combining the base material 20, the first fixing member 21, the second fixing member 22, and the volume hologram 18, in the first axis rotation angle adjustment step, the first axis rotation angle of the volume hologram 18 about the first axis. Adjust. The first axis rotation angle of the volume hologram 18 is adjusted by rotating the first fixing member 21 around the first convex portion 27 with respect to the base material 20. The first convex portion 27 can freely rotate in the first concave portion 26 until the first fixing member 21 is fixed to the substrate 20. By using the first convex portion 27 and the first concave portion 26, the first fixing member 21 can adjust the first axis rotation angle around the first convex portion 27 with respect to the base material 20. In the second axis rotation angle adjustment step, the second axis rotation angle of the volume hologram 18 around the second axis is adjusted. The second axis rotation angle of the volume hologram 18 is adjusted by rotating the second fixing member 22 around the second convex portion 25 with respect to the first fixing member 21. The second convex portion 25 can freely rotate on the second concave portion 28 until the second fixing member 22 is fixed to the first fixing member 21. The second fixing member 22 can adjust the second axis rotation angle around the second convex portion 25 with respect to the first fixing member 21 by using the second convex portion 25 and the second concave portion 28.

  The first axis rotation angle and the second axis rotation angle of the volume hologram 18 are adjusted so that the interference fringes of the volume hologram 18 are perpendicular to the light beam from the semiconductor element 11. The adjustment of the first axis rotation angle and the second axis rotation angle of the volume hologram 18 is performed by, for example, entering the adjustment light into the volume hologram 18 and maximizing the intensity of the light emitted from the volume hologram 18. This can be done by finding the rotation angle and the second axis rotation angle. The first axis rotation angle adjustment step and the second axis rotation angle adjustment step may be performed in parallel. In the VHG, interference fringes are not necessarily parallel to the surface constituting the outer shape of the VHG, and are often inclined relatively greatly. For this reason, the rotation angle adjustment according to the present invention is particularly effective for VHG.

  Next, in the external resonator fixing step, the volume hologram 18 is fixed in a state where the first axis rotation angle and the second axis rotation angle are adjusted. The 1st fixing member 21 is fixed to the base material 20 by adhere | attaching the 1st fixing surface 31 and the bottom face 35 using an adhesive agent. The second fixing member 22 is fixed to the first fixing member 21 by bonding the second fixing surface 32 and the side surface 36 using an adhesive. The volume hologram 18 is fixed to the second fixing member 22 by bonding the third fixing surface 33 and the side surface 37 using an adhesive. Note that the step of fixing the volume hologram 18 to the second fixing member 22 in the external resonator fixing step may be before the first axis rotation angle adjustment step and the second axis rotation angle adjustment step.

  FIG. 5 illustrates the fixation of the volume hologram 18 using the first fixing member 21 and the second fixing member 22. As an adhesive for adhering each member, for example, an ultraviolet curable adhesive or a thermosetting adhesive can be used. In the case of using an ultraviolet curable adhesive or a thermosetting adhesive, the adhesive can be cured after the adhesive is injected and the first and second axis rotation angles of the volume hologram 18 are adjusted. Thereby, the volume hologram 18 can be fixed in a state where the first axis rotation angle and the second axis rotation angle are adjusted.

  A first adhesive member that bonds the first fixing member 21 to the first fixing surface 31 is formed on the contact portion 41 of the first fixing surface 31 and the bottom surface 35. The first adhesive member is obtained by curing an adhesive that bonds the first fixed surface 31 and the bottom surface 35. A contact portion 42 between the second fixing surface 32 and the side surface 36 is formed with a second adhesive member that bonds the second fixing member 22 to the second fixing surface 32. The second adhesive member is obtained by curing an adhesive that bonds the second fixed surface 32 and the side surface 36. A third adhesive member that adheres the volume hologram 18 to the third fixed surface 33 is formed on the contact portion 43 of the third fixed surface 33 and the side surface 37. The third adhesive member is obtained by curing an adhesive that bonds the third fixing surface 33 and the side surface 37. In the figure, the contact portions 41, 42, and 43 are indicated by thick lines.

  The first shaft rotation angle of the first fixing member 21 is fixed by fixing the first fixing member 21 to the first fixing surface 31 by the first adhesive member. The first fixing surface 31 also serves to reduce the rotational deviation of the first fixing member 21 in directions other than the rotation direction around the first convex portion 27. By fixing the second fixing member 22 to the second fixing surface 32 by the second adhesive member, the second axis rotation angle of the second fixing member 22 is fixed. The second fixing surface 32 serves to reduce the rotational deviation of the second fixing member 22 in directions other than the rotation direction centered on the second convex portion 25. Further, the third fixed surface 33 serves to reduce the rotational deviation of the volume hologram 18 in each direction. As described above, the volume hologram 18 can be fixed in a state where the first axis rotation angle and the second axis rotation angle are accurately adjusted.

  In the light source device 10 of the present invention, by using the first fixing member 21 and the second fixing member 22, it is not necessary to adjust the rotation angle of the volume hologram 18 by changing the thickness of the adhesive layer. Even when an adhesive layer is formed on the contact portions 41, 42, and 43, the adhesive layer can have a substantially uniform thickness. If the adhesive layer has a substantially uniform thickness, the amount of expansion and contraction of the adhesive layer due to temperature changes is also substantially uniform. For this reason, the change of the rotation angle of the volume hologram 18 due to the temperature change can be reduced. By reducing the change in the rotation angle of the volume hologram 18, laser oscillation with high efficiency can be continued. As a result, the change in the rotation angle of the external resonator can be reduced, and the laser beam can be emitted with high efficiency.

  The external resonator fixing portion is not limited to the configuration in which the first fixing member 21 is provided with the first adjustment shaft and the base member 20 is provided with the first bearing portion, but the base member 20 has the first adjustment shaft and the first fixing member 21. Alternatively, the first bearing portion may be provided respectively. Further, the external resonator fixing portion is not limited to the configuration in which the second fixing member 22 is provided with the second adjustment shaft and the first fixing member 21 is provided with the second bearing portion, but the first fixing member 21 has the second adjustment shaft, 2 The structure which provides a 2nd bearing part in the fixing member 22, respectively may be sufficient.

  The first axis and the second axis are not limited to the Y axis and the X axis, respectively, and can be set as appropriate. The shapes of the base material 20, the first fixing member 21, and the second fixing member 22 are not particularly limited as long as the first rotation angle and the second rotation angle of the volume hologram 18 can be adjusted. For example, the first fixing member 21 may be disposed on the surface of the substrate 20 on which the semiconductor element 11 and the like are disposed without providing the step portion 23 on the substrate 20. The external resonator only needs to resonate the light emitted from the semiconductor element 11 and is not limited to the volume hologram 18. The light source device 10 may be, for example, a semiconductor laser pumped solid state (DPSS) laser. The light source device 10 may be provided with optical elements such as a polarization selection filter and a wavelength selection filter as necessary.

  FIG. 6 illustrates a first modification of the present embodiment. This modification is characterized by having a first fixing member 50 provided with a first through hole 51 and a second through hole 52. The plurality of first through holes 51 are provided in a portion of the first fixing member 50 that is formed substantially parallel to the XZ plane. The first through hole 51 penetrates between the bottom surface 35 (see FIG. 4) that is the surface facing the first fixing surface 31 of the first fixing member 50 and the upper surface 53 opposite to the bottom surface 35. As shown in the figure, the first through hole 51 is provided not only on the front side of the paper with respect to the volume hologram 18 but also on the back side of the paper.

  The second through hole 52 is provided in a portion of the first fixing member 50 that is formed substantially parallel to the YZ plane. The second through hole 52 penetrates between the second fixing surface 32 of the first fixing member 50 and the side surface 54 that is the surface opposite to the second fixing surface 32. As shown in the figure, the second through hole 52 is not only provided in the vicinity of the second convex portion 25 on the front side of the paper surface, but is also provided in the vicinity of the second convex portion 25 on the back side of the paper surface.

  FIG. 7 shows a cross-sectional configuration of the first through hole 51 and a portion around the first through hole 51. The adhesive layer 55 is formed inside the first through hole 51. The adhesive layer 55 is a first adhesive member that adheres the first fixing member 50 to the first fixing surface 31. The adhesive layer 55 is obtained by curing an ultraviolet curable adhesive. By injecting the adhesive from the first through hole 51, the adhesive can be spread over a wide range of the contact portion 41. In addition, after the adhesive is injected, the adhesive can be cured in a wide range within the contact portion 41 and the first through hole 51 by irradiating ultraviolet rays through the first through hole 51. The same applies to the second through hole 52 as in the case of the first through hole 51. Thereby, the 1st fixing surface 31, the 1st fixing member 50, the 2nd fixing surface 32, and the 2nd fixing member 22 can be fixed firmly. The positions, shapes, and numbers of the first through holes 51 and the second through holes 52 are not limited to those shown in the drawings, and may be changed as appropriate.

  FIG. 8 illustrates a second modification of the present embodiment. This modification is characterized by having a first screw portion 57 and a second screw portion 58 provided in place of the adhesive member. The first screw portion 57 fixes the first fixing member 50 to the first fixing surface 31. The plurality of first screw portions 57 are provided in a portion of the first fixing member 50 that is formed substantially parallel to the XZ plane. The first screw portion 57 is provided so as to penetrate from the upper surface 53 opposite to the bottom surface 35 to the base material 20. As shown in the figure, the first screw portion 57 is provided not only on the front side of the paper with respect to the volume hologram 18 but also on the back side of the paper. By using the first screw part 57, it is possible to suppress the peeling of the first fixing member 50 from the first fixing surface 31.

  The second screw portion 58 fixes the second fixing member 22 to the second fixing surface 32. The plurality of second screw portions 58 are provided in a portion of the first fixing member 50 that is formed substantially parallel to the YZ plane. The second screw portion 58 is provided so as to penetrate from the side surface 54, which is the surface opposite to the second fixing surface 32, to the second fixing member 22. As shown in the figure, the second screw portion 58 is provided not only near the second convex portion 25 on the front side of the paper but also near the second convex portion 25 on the back side of the paper. By using the second screw portion 58, the peeling of the second fixing member 22 from the second fixing surface 32 can be suppressed. The light source device 10 can ensure high reliability by enabling the first screw member 57 and the second screw member 58 to suppress the peeling of the first fixing member 50 and the second fixing member 22. Moreover, by using the 1st screw part 57 and the 2nd screw part 58, compared with the case where an adhesive agent is used, the time which fixing requires can be shortened.

  FIG. 9 illustrates a third modification of the present embodiment. This modification is characterized by having a first structure 61 and a second structure 62. The first structure 61 and the second structure 62 sandwich the volume hologram 18. The 1st structure 61 and the 2nd structure 62 are corresponded to the part formed substantially parallel to the YZ surface among said 2nd fixing members 22 (refer FIG. 4). The first structure 61 and the second structure 62 are paired and function as a second fixing member. The second protrusion 25 is provided on the side surface 36 of the first structure 61 and the side surface 36 of the second structure 62.

  The first structure 61 and the second structure 62 have a fitting portion 63 formed so that a portion near the side surface 37 of the volume hologram 18 can be fitted. The first structure 61 and the second structure 62 have a third fixing surface 33 (see FIG. 4) that faces the side surface 37 of the fitting portion 63. A second fixing surface 32 (see FIG. 4) of the first fixing member 21 that faces the side surface 36 of the first structure 61 fixes the first structure 61. The second fixing surface 32 of the first fixing member 21 that faces the side surface 36 of the second structure 62 fixes the second structure 62. Also in this modification, the volume hologram 18 can be fixed. Further, by using the first structure 61 and the second structure 62, a portion of the second fixing member 22 formed substantially parallel to the XZ plane can be omitted, and the volume hologram is located at a position close to the first fixing member 21. 18 can be arranged. Thereby, the light source device 10 can be reduced in size.

  FIG. 10 illustrates a fourth modification of the present embodiment. This modification is characterized in that a gap 66 is provided between the second structure 62 and the first fixing member 65. The first fixing member 65 has a bearing hole 67 through which the second convex portion 25 passes. The bearing hole 67 functions as a second bearing portion that receives and supports the second convex portion 25.

  The second fixing surface 32 (see FIG. 4) of the first fixing member 65 that faces the side surface 36 (see FIG. 9) of the first structure 61 fixes the first structure 61. On the other hand, the second structure 62 is not fixed to the surface of the first fixing member 65 that faces the side surface 36 of the second structure 62, and a gap is formed between the first fixing member 65 and the second structure 62. 66 is provided. By passing the second convex portion 25 through the bearing hole 67, it is possible to prevent the second structure 62 from falling due to the provision of the gap 66.

  When the volume hologram 18 is thermally expanded, the volume hologram 18 can be extended to the side where the gap 66 is provided. By freely expanding the volume hologram 18, the generation of stress in the volume hologram 18 can be reduced. By making it possible to reduce the distortion of the volume hologram 18, changes in the wavelength characteristics of the volume hologram 18 and a decrease in reflectance can be reduced. The second fixing surface 32 may be any one of the surface of the first fixing member 65 that faces the first structure 61 and the surface that faces the second structure 62.

  FIG. 11 shows a schematic configuration of a monitor device 70 according to the second embodiment of the present invention. The monitor device 70 includes a device main body 71 and an optical transmission unit 72. The apparatus main body 71 includes the light source apparatus 10 (see FIG. 1) of the first embodiment. The light transmission unit 72 includes two light guides 74 and 75. A diffusion plate 76 and an imaging lens 77 are provided at the end of the light transmission unit 72 on the subject (not shown) side. The first light guide 74 transmits light from the light source device 10 to the subject. The diffusion plate 76 is provided on the emission side of the first light guide 74. The light propagating through the first light guide 74 is diffused on the subject side by passing through the diffusion plate 76. Each part in the optical path from the light source device 10 to the diffusion plate 76 constitutes an illumination device that illuminates the subject.

  The second light guide 75 transmits light from the subject to the camera 73. The imaging lens 77 is provided on the incident side of the second light guide 75. The imaging lens 77 collects light from the subject onto the incident surface of the second light guide 75. Light from the subject enters the second light guide 75 through the imaging lens 77, then propagates through the second light guide 75 and enters the camera 73.

  As the first light guide 74 and the second light guide 75, a bundle of many optical fibers can be used. By using an optical fiber, light can be transmitted far away. The camera 73 is provided in the apparatus main body 71. The camera 73 is an imaging unit that captures an image of a subject illuminated by light from the light source device 10. By making the light incident from the second light guide 75 enter the camera 73, the subject can be imaged by the camera 73. By using the light source device 10 of the first embodiment, the object can be illuminated with high efficiency. As a result, a bright image can be monitored using light supplied with high efficiency.

  FIG. 12 shows a schematic configuration of a projector 80 according to Embodiment 3 of the present invention. The projector 80 is a front projection type projector that views light by supplying light to the screen 89 and observing light reflected by the screen 89. The projector 80 includes a red (R) light source device 81R, a green (G) light source device 81G, and a blue (B) light source device 81B. Each of the color light source devices 81R, 81G, 81B has the same configuration as the light source device 10 (see FIG. 1) of the first embodiment. The projector 80 is an image display device that displays an image using light from each color light source device 81R, 81G, 81B.

  The light source device for R light 81R is a light source device that supplies R light. The diffusing element 82 shapes and enlarges the illumination area, and uniformizes the light amount distribution in the illumination area. As the diffusing element 82, for example, a computer generated hologram (CGH) which is a diffractive optical element can be used. The field lens 83 collimates the light from the R light source device 81R and makes it incident on the R light spatial light modulator 84R. The R light source device 81R, the diffusing element 82, and the field lens 83 constitute an illumination device that illuminates the R light spatial light modulator 84R. The R light spatial light modulator 84R is a spatial light modulator that modulates R light from the illumination device in accordance with an image signal, and is a transmissive liquid crystal display device. The R light modulated by the R light spatial light modulator 84R enters the cross dichroic prism 85 which is a color synthesis optical system.

  The G light source device 81G is a light source device that supplies G light. The light that has passed through the diffusing element 82 and the field lens 83 enters the G spatial light modulator 84G. The G light source device 81G, the diffusing element 82, and the field lens 83 constitute an illumination device that illuminates the G light spatial light modulator 84G. The G light spatial light modulator 84G is a spatial light modulator that modulates the G light from the illumination device according to an image signal, and is a transmissive liquid crystal display device. The G light modulated by the G light spatial light modulator 84G is incident on a different surface of the cross dichroic prism 85 from the surface on which the R light is incident.

  The light source device 81B for B light is a light source device that supplies B light. The light that has passed through the diffusing element 82 and the field lens 83 enters the B light spatial light modulator 84B. The light source device 81B for B light, the diffusing element 82, and the field lens 83 constitute an illumination device that illuminates the spatial light modulation device 84B for B light. The B light spatial light modulator 84B is a spatial light modulator that modulates the B light from the illumination device in accordance with an image signal, and is a transmissive liquid crystal display device. The B light modulated by the B light spatial light modulator 84B is incident on a surface of the cross dichroic prism 85 that is different from the surface on which the R light is incident and the surface on which the G light is incident. As the transmissive liquid crystal display device, for example, a high temperature polysilicon TFT liquid crystal panel (HTPS) can be used.

  The cross dichroic prism 85 has two dichroic films 86 and 87 arranged substantially orthogonal to each other. The first dichroic film 86 reflects R light and transmits G light and B light. The second dichroic film 87 reflects B light and transmits R light and G light. The cross dichroic prism 85 combines R light, G light, and B light incident from different directions and emits the light toward the projection lens 88. The projection lens 88 projects the light combined by the cross dichroic prism 85 toward the screen 89.

  By using each color light source device 81R, 81G, 81B having the same configuration as the light source device 10 described above, laser light can be emitted with high efficiency. As a result, a bright image can be displayed using light supplied with high efficiency. The projector 80 is not limited to the case where each of the light source device for R light 81R, the light source device for G light 81G, and the light source device for B light 81B has the same configuration as that of the light source device 10 of the above embodiment. For example, the R light source device 81 </ b> R may emit the fundamental wave light from the light source unit without using the SHG element.

  The projector is not limited to the case where a transmissive liquid crystal display device is used as the spatial light modulation device. As the spatial light modulator, a reflective liquid crystal display (Liquid Crystal On Silicon; LCOS), DMD (Digital Micromirror Device), GLV (Grating Light Valve), or the like may be used. The projector is not limited to a configuration including a spatial light modulator for each color light. The projector may be configured to modulate two or three or more color lights with one spatial light modulator. The projector is not limited to the case where the spatial light modulator is used. The projector may be a laser scanning projector that scans the laser light from the light source device by scanning means such as a galvanometer mirror and displays an image on the irradiated surface. The projector may be a slide projector that uses a slide having image information. The projector may be a so-called rear projector that supplies light to one surface of the screen and observes an image by observing light emitted from the other surface of the screen.

  The light source device of the present invention may be applied to a liquid crystal display that is an image display device. By combining the light source device of the present invention and the light guide plate, it can be used as an illumination device for illuminating the liquid crystal panel. Also in this case, a bright and high-quality image can be displayed. The light source device of the present invention is not limited to being applied to a monitor device or an image display device. The light source device of the present invention may be used, for example, in an optical system such as an exposure device for laser beam exposure or a laser processing device.

  As described above, the light source device according to the present invention is suitable for use in a monitor device or an image display device.

The figure which shows the perspective structure of the light source device which concerns on Example 1 of this invention. The figure which shows the structure which removed the optical prism from the light source device. The figure which shows the YZ cross-section structure of a light source device. The figure which shows a base material, a 1st fixing member, a 2nd fixing member, and a volume hologram. The figure explaining fixation of the volume hologram using a 1st fixing member etc. FIG. 6 is a diagram for explaining a first modification of the first embodiment. The figure which shows the cross-sectional structure of the peripheral part of a 1st through-hole and a 1st through-hole. FIG. 6 is a diagram illustrating a second modification of the first embodiment. FIG. 6 is a diagram for explaining a third modification of the first embodiment. FIG. 6 is a diagram illustrating a fourth modification of the first embodiment. The figure which shows schematic structure of the monitor apparatus which concerns on Example 2 of this invention. FIG. 6 is a diagram illustrating a schematic configuration of a projector according to a third embodiment of the invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Light source device, 11 Semiconductor element, 12 Submount, 13 Prism support part, 14 Optical prism, 15 Dichroic film | membrane, 16 SHG element, 17 SHG element support part, 18 Volume hologram, 20 Base material, 21 1st fixing member, 22 2nd fixing member, 23 level | step difference part, 25 2nd convex part, 26 1st recessed part, 27 1st convex part, 28 2nd recessed part, 31 1st fixing surface, 32 2nd fixing surface, 33 3rd fixing surface, 35 Bottom surface, 36 side surface, 37 side surface, 41, 42, 43 contact portion, 50 first fixing member, 51 first through hole, 52 second through hole, 53 upper surface, 54 side surface, 55 adhesive layer, 57 first screw portion, 58 2nd thread part, 61 1st structure, 62 2nd structure, 63 fitting part, 65 1st fixing member, 66 clearance gap, 67 bearing hole, 70 monitor apparatus, 71 apparatus main body, 2 light transmission unit, 73 camera, 74 first light guide, 75 second light guide, 76 diffuser plate, 77 imaging lens, 80 projector, 81RR light source device, 81G light source device, 81B light source Light source device, 82 diffusing element, 83 field lens, 84R R light spatial light modulator, 84G G light spatial light modulator, 84BB light spatial light modulator, 85 cross dichroic prism, 86 first dichroic film, 87 Second dichroic film, 88 projection lens, 89 screen

Claims (15)

A light source that emits light;
An external resonator that resonates the light emitted by the light source unit;
A first adjustment axis for adjusting a first axis rotation angle of the external resonator centered on the first axis, and the external resonator centered on a second axis that is an axis substantially orthogonal to the first axis An external resonator fixing portion for fixing the external resonator in a state in which the first axis rotation angle and the second axis rotation angle are adjusted. And a light source device. A base material on which the light source unit is disposed;
The external resonator fixing portion includes a first fixing member whose first axis rotation angle is adjusted with respect to the base material by the first adjustment shaft, and the first fixing member by the second adjustment shaft. The light source device according to claim 1, further comprising: a second fixing member in which the second shaft rotation angle is adjusted. A first bearing portion for supporting the first adjustment shaft;
The light source device according to claim 2, comprising at least one of a second bearing portion that receives and supports the second adjustment shaft. A first fixing surface provided on the base material and fixing the first fixing member;
A second fixing surface provided on the first fixing member and fixing the second fixing member;
The light source device according to claim 2, further comprising at least one of a third fixing surface provided on the second fixing member and fixing the external resonator. A first adhesive member for adhering the first fixing member to the first fixing surface;
A second adhesive member for adhering the second fixing member to the second fixing surface;
The light source device according to claim 4, comprising at least one of a third adhesive member that adheres the external resonator to the third fixed surface.   The first fixing member includes a first through hole that penetrates a surface of the first fixing member that faces the first fixing surface, and a surface opposite to the surface that faces the first fixing surface, The first fixing member has at least one of the second fixing surface and a second through-hole penetrating a surface opposite to the second fixing surface. The light source device described. A first screw portion for fixing the first fixing member to the first fixing surface;
The light source device according to any one of claims 4 to 6, further comprising at least one of a second screw portion that fixes the second fixing member to the second fixing surface. The second fixing member has a first structure and a second structure,
The light source device according to claim 2, wherein the first structure body and the second structure body sandwich the external resonator.   The said 2nd fixing surface is any one of the surface which opposes the said 1st structure among the said 1st fixing members, and the surface which opposes the said 2nd structure. Light source device.   10. The light source device according to claim 1, wherein each of the first axis and the second axis is substantially orthogonal to a light beam incident on the external resonator from the light source unit.   The light source device according to claim 1, wherein the external resonator includes a volume hologram that diffracts light from the light source unit. A method of manufacturing a light source device having an external resonator for resonating light from a light source unit,
A first axis rotation angle adjustment step of adjusting a first axis rotation angle of the external resonator around the first axis using a first adjustment axis;
A second axis rotation angle adjusting step of adjusting a second axis rotation angle of the external resonator around the second axis, which is an axis substantially orthogonal to the first axis, using a second adjustment axis;
An external resonator fixing step of fixing the external resonator in a state where the first axis rotation angle and the second axis rotation angle are adjusted.   An illumination device comprising the light source device according to any one of claims 1 to 11 and illuminating an object to be irradiated using light from the light source device. A lighting device according to claim 13;
An image pickup unit for picking up an image of a subject illuminated by the illumination device.   An image display device comprising the light source device according to claim 1, wherein an image is displayed using light from the light source device.

Images