JP2018085252A - Light source device, illumination device, and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source device having a large allowable error of mounting positions of luminous elements.SOLUTION: A light source device comprises: a light-emitting section comprising a first luminous element and a second luminous element arrayed in a first direction; a first collimation optical system to which first light emitted from the first luminous element is made incident; and a second collimation optical system to which second light emitted from the second luminous element is made incident. The first light and the second light are individually emitted from the light-emitting section in a third direction and a fourth direction inclined from a second direction vertical to the first direction. An angle between a principal ray of the first light and the second direction and an angle between a principal ray of the second light and the second direction are individually decreased by the first collimation optical system and the second collimation optical system.SELECTED DRAWING: Figure 4

Description

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

  For example, a light source device using a laser element has been proposed as a light source device used for a projector. In the following Patent Document 1, a phosphor layer containing a phosphor, an excitation light source having a plurality of laser diodes that emit excitation light for exciting the phosphor, a collimating lens array having a plurality of collimating lenses, A light source device including a lens and a dichroic mirror is disclosed.

  In the above light source device, the plurality of laser diodes are provided on one plane, and the collimating lens array is provided in parallel with the plane. Each laser diode emits laser light perpendicular to its plane. The focal length of the collimating lens is set equal to the distance between the laser diode and the collimating lens. Laser light emitted from one laser diode is collimated by a corresponding collimator lens, and is irradiated onto a predetermined region of the phosphor layer by a condenser lens. Fluorescent light emitted from the predetermined region is collimated by a condensing lens and reflected toward a subsequent optical system by a dichroic mirror.

JP 2012-108486 A

  In the light source device of Patent Document 1, when the relative relationship between the optical axis of the laser diode and the optical axis of the collimator lens is deviated from a predetermined relationship, the irradiation region of the laser light on the phosphor layer is changed from the predetermined region. It will shift. In this case, the region where the fluorescent light is emitted from the phosphor layer is also shifted from the predetermined region. Since the fluorescent light emitted from outside the predetermined region is not condensed in an appropriate state by the condenser lens, there arises a problem that the utilization efficiency of the fluorescent light in the subsequent optical system is low.

  One aspect of the present invention is made to solve the above-described problem, and provides a light source device that has a larger tolerance than the conventional one with respect to the relative relationship between the optical axis of a light emitting element and a collimating lens. Is one of the purposes. An object of one embodiment of the present invention is to provide an illumination device including the light source device. One aspect of the present invention is to provide a projector including the light source device described above.

  In order to achieve the above object, a light source device according to an aspect of the present invention includes a light emitting unit including a first light emitting element and a second light emitting element arranged in a first direction, and the first light emitting device. A first collimating optical system on which the first light emitted from the light emitting element is incident; and a second collimating optical system on which the second light emitted from the second light emitting element is incident. The light emitting unit emits the first light from the light emitting unit in a third direction inclined from a second direction perpendicular to the first direction, and the second light is inclined fourth from the second direction. The light emitting unit is configured to emit in the direction. In the first collimating optical system, an angle formed between the principal ray of the first light emitted from the first collimating optical system and the second direction is not incident on the first collimating optical system. It arrange | positions so that it may become smaller than the angle which the principal ray of the said 1st light and the said 2nd direction make. The second collimating optical system is configured so that an angle formed between the principal ray of the second light emitted from the second collimating optical system and the second direction is not incident on the second collimating optical system. It arrange | positions so that it may become smaller than the angle which the principal ray of the said 2nd light and the said 2nd direction make.

  In this specification, a plane (virtual plane) that includes the first light-emitting element and the second light-emitting element and is perpendicular to the second direction is referred to as a light-emitting element array surface. A plane (virtual surface) including the first collimating optical system and the second collimating optical system and perpendicular to the second direction is referred to as an arrangement surface of the collimating optical system. A plurality of collimating optical systems including the first collimating optical system and the second collimating optical system may be collectively referred to as a collimating optical system.

  In the following description, it is assumed that the arrangement surface of the collimating optical system is parallel to the arrangement surface of the light emitting elements, and the distance between the arrangement surface of the light emitting elements and the arrangement surface of the collimating optical system is fixed. Since the interval is fixed, the larger the angle formed between the third direction and the second direction, the longer the distance between one light emitting element and the corresponding collimating optical system, and a longer collimating optical system with a focal length. Can be used. The longer the focal length, the smaller the influence of the relative relationship between the optical axis of the light emitting element and the optical axis of the collimating optical system. Therefore, in the light source device according to one aspect of the present invention, the allowable error with respect to the relative relationship between the optical axis of the light emitting element and the corresponding collimating optical system is larger than the conventional one.

  In the light source device of one aspect of the present invention, the first collimating optical system has at least one first lens surface, and the second collimating optical system has at least one second lens surface. An incident angle of the principal ray of the first light with respect to the first lens surface is greater than 0 ° and less than 90 °, and the principal ray of the second light with respect to the second lens surface is The incident angle may be larger than 0 ° and smaller than 90 °.

  According to this configuration, the tolerance for the relative relationship between the optical axis of the light emitting element and the collimating optical system to which the light emitting element corresponds is larger than in the past.

  In the light source device of one aspect of the present invention, when viewed from a direction perpendicular to the second direction and the third direction, the second direction is located between the third direction and the fourth direction. It may be.

  This light source device emits a light beam having a highly symmetrical intensity distribution around the second direction while having a larger tolerance than in the past. Therefore, the light source device having the above configuration is suitable for an optical system that requires a highly symmetrical intensity distribution.

  In the light source device according to one aspect of the present invention, the light emitting unit further includes a third light emitting element, and the third light emitted from the third light emitting element is tilted from the second direction. The second light-emitting element is configured to emit in five directions, and when viewed from a direction perpendicular to the second direction and the third direction, the second light-emitting element includes the first light-emitting element and the third light-emitting element. The fourth direction is located between the second direction and the fifth direction, and the chief ray of the third light and the second light when emitted from the light emitting unit The angle formed by the direction may be larger than the angle formed by the principal ray of the second light and the second direction when emitted from the light emitting unit.

  According to this configuration, the allowable error at the outer periphery of the light emitting unit is larger than the allowable error at the center of the light emitting unit. Therefore, the influence of the relative relationship as the entire light emitting unit is smaller. Further, the intervals between the principal rays emitted from the collimating optical system can be made equal to each other.

  In the light source device according to one aspect of the present invention, the third direction may be parallel to the fourth direction.

  In this light source device, the first light and the second light arranged at substantially the same pitch as the pitch of the first light emitting element and the second light emitting element, as in the past, while having a larger tolerance than the conventional one. Is injected.

  In the light source device according to one aspect of the present invention, the light emitting unit further includes a first reflecting surface and a second reflecting surface, and the first light is emitted from the first light emitting element in the first direction. The first light emitted from the first light emitting element is reflected in the third direction by the first reflecting surface, and the second light is emitted from the first light emitting element. The second light emitted from the light emitting element substantially parallel to the first direction and the second light emitted from the second light emitting element is reflected by the second reflecting surface in the fourth direction. Also good.

  According to this configuration, the emission direction of the first light can be adjusted by the inclination angle of the first reflection surface, and the emission direction of the second light can be adjusted by the inclination angle of the second reflection surface. There is no need to provide an inclined surface on a support member (for example, a submount) on which the light emitting element is mounted. Thereby, the mounting structure of the light emitting element can be simplified, and the manufacture of the light source device can be facilitated. In addition, since the light emitting element is mounted so that light is emitted substantially parallel to the first direction, the side surface perpendicular to the light emitting surface of the light emitting element is arranged in parallel to the support surface of the support member. . Since the area of the side surface is larger than the area of the light emitting surface, the heat of the light emitting element can be efficiently transferred to the support member via the side surface of the light emitting element.

  An illumination device according to one aspect of the present invention includes the light source device according to one aspect of the present invention.

  Since the illumination device according to one aspect of the present invention includes the light source device according to one aspect of the present invention, the light use efficiency is excellent.

  The illumination device according to one aspect of the present invention may further include a phosphor layer on which at least a part of the first light and the second light is incident.

  According to this configuration, the color of the illumination light emitted from the illumination device can be adjusted.

  A projector according to one aspect of the present invention is modulated by the illumination device according to one aspect of the present invention, a light modulation device that modulates illumination light emitted from the illumination device according to image information, and the light modulation device. A projection optical system for projecting the light.

  Since the projector according to one aspect of the present invention includes the illumination device according to one aspect of the present invention, it is excellent in light use efficiency.

It is a schematic block diagram of the projector of 1st Embodiment. It is a schematic block diagram of the illuminating device of 1st Embodiment. It is a top view of the light source device of 1st Embodiment. It is sectional drawing which follows the IV-IV line of FIG. It is a figure which shows the positional relationship of the light emitting element and light source image in the conventional light source device. It is a figure which shows the positional relationship of the light emitting element and light source image in the light source device of this embodiment. It is a top view of the light source device of 2nd Embodiment. It is sectional drawing which follows the VIII-VIII line of FIG. It is sectional drawing which follows the IX-IX line of FIG. It is sectional drawing which looked at the light source device of 3rd Embodiment from the direction perpendicular | vertical to XZ plane. It is sectional drawing which looked at the light source device of 3rd Embodiment from the direction perpendicular | vertical to a YZ plane. It is a perspective view of the collimating optical system of the light source device of 3rd Embodiment. It is sectional drawing seen from the direction perpendicular | vertical to the light source device YZ plane of 4th Embodiment. It is sectional drawing which looked at the light source unit of 4th Embodiment from the direction perpendicular | vertical to XZ plane. It is sectional drawing which looked at the light source unit of 4th Embodiment from the direction perpendicular | vertical to a YZ plane.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In addition, in the drawings used in the following description, in order to make the features easy to understand, there are cases where the portions that become the features are enlarged for convenience, and the dimensional ratios of the respective components are the same as the actual ones. Not exclusively.

[First Embodiment]
The projector according to the first embodiment is an example of a projector using three transmissive liquid crystal light valves.
FIG. 1 is a schematic configuration diagram illustrating a projector according to the present embodiment. FIG. 2 is a schematic configuration diagram showing the illumination device of the present embodiment.

(projector)
As shown in FIG. 1, the projector 1 of this embodiment is a projection type image display device that displays a color image on a screen SCR. The projector 1 includes an illumination device 70, a uniform illumination optical system 40, a color separation optical system 3, a light modulation device 4R for red light, a light modulation device 4G for green light, and a light modulation device 4B for blue light. , A combining optical system 5 and a projection optical system 60 are provided.

  The illumination device 70 emits white illumination light WL toward the uniform illumination optical system 40. The illuminating device 70 includes a light source device of the present embodiment described later.

  The uniform illumination optical system 40 includes a homogenizer optical system 31, a polarization conversion element 32, and a superimposing optical system 33. The homogenizer optical system 31 includes a first multi-lens array 31a and a second multi-lens array 31b. The uniform illumination optical system 40 uniformizes the intensity distribution of the illumination light WL emitted from the illumination device 70 in the light modulation device 4R, the light modulation device 4G, and the light modulation device 4B, which are illuminated areas. The illumination light WL emitted from the uniform illumination optical system 40 enters the color separation optical system 3.

  The color separation optical system 3 separates the illumination light WL emitted from the illumination device 70 into red light LR, green light LG, and blue light LB. The color separation optical system 3 includes a first dichroic mirror 7a, a second dichroic mirror 7b, a first reflection mirror 8a, a second reflection mirror 8b, a third reflection mirror 8c, and a first A relay lens 9a and a second relay lens 9b are provided.

  The first dichroic mirror 7a separates the illumination light WL emitted from the illumination device 70 into red light LR and light including green light LG and blue light LB. The first dichroic mirror 7a transmits the red light LR and reflects the green light LG and the blue light LB. The second dichroic mirror 7b separates the light reflected by the first dichroic mirror 7a into green light LG and blue light LB. The second dichroic mirror 7b reflects the green light LG and transmits the blue light LB.

  The first reflection mirror 8a is disposed in the optical path of the red light LR. The first reflection mirror 8a reflects the red light LR transmitted through the first dichroic mirror 7a toward the light modulation device 4R. The second reflection mirror 8b and the third reflection mirror 8c are arranged in the optical path of the blue light LB. The second reflection mirror 8b and the third reflection mirror 8c guide the blue light LB transmitted through the second dichroic mirror 7b to the light modulation device 4B. The green light LG is reflected by the second dichroic mirror 7b and travels toward the light modulation device 4G.

  The first relay lens 9a and the second relay lens 9b are disposed on the light emission side of the second dichroic mirror 7b in the optical path of the blue light LB. The first relay lens 9a and the second relay lens 9b compensate for the optical loss of the blue light LB caused by the optical path length of the blue light LB being longer than the optical path lengths of the red light LR and the green light LG.

  The light modulation device 4R modulates the red light LR according to the image information, and forms image light corresponding to the red light LR. The light modulation device 4G modulates the green light LG according to the image information, and forms image light corresponding to the green light LG. The light modulation device 4B modulates the blue light LB according to the image information, and forms image light corresponding to the blue light LB. For example, a transmissive liquid crystal panel is used for the light modulation device 4R, the light modulation device 4G, and the light modulation device 4B. Further, polarizing plates (not shown) are arranged on the light incident side and the light emission side of the liquid crystal panel, respectively. The polarizing plate transmits linearly polarized light having a specific polarization direction.

  A field lens 10R is disposed on the light incident side of the light modulation device 4R. A field lens 10G is disposed on the light incident side of the light modulation device 4G. A field lens 10B is disposed on the light incident side of the light modulation device 4B. The field lens 10R collimates the red light LR incident on the light modulation device 4R. The field lens 10G collimates the green light LG incident on the light modulation device 4G. The field lens 10B collimates the blue light LB incident on the light modulation device 4B.

  The combining optical system 5 combines the image light corresponding to each of the red light LR, the green light LG, and the blue light LB, and emits the combined image light toward the projection optical system 60. For example, a cross dichroic prism is used for the combining optical system 5.

  The projection optical system 60 includes a projection lens group including a plurality of projection lenses. The projection optical system 60 enlarges and projects the image light combined by the combining optical system 5 toward the screen SCR. As a result, an enlarged color image is displayed on the screen SCR.

(Lighting device)
Hereinafter, the illumination device 70 will be described.
FIG. 2 is a schematic configuration diagram of the illumination device 70 of the present embodiment.
As shown in FIG. 2, the illumination device 70 includes a light source device 2, a homogenizer optical system 25, a first retardation plate 26a, a polarization beam splitter 27, a first pickup optical system 28, a ring-shaped device. A phosphor wheel (wavelength conversion element) 29 including a phosphor layer 47, a second retardation plate 26b, a second pickup optical system 41, and a rotary diffusing element 42 are provided. Hereinafter, the polarizing beam splitter is abbreviated as PBS.

  The light source device 2, the homogenizer optical system 25, the first phase difference plate 26a, the PBS 27, the second phase difference plate 26b, and the second pickup optical system 41 are disposed on the optical axis AX0. Yes. The first pickup optical system 28 is disposed on the optical axis AX1 orthogonal to the optical axis AX0.

  The homogenizer optical system 25 makes the intensity distribution of the light beam emitted from the light source device 2 uniform in the illuminated area. The homogenizer optical system 25 includes, for example, a first multi-lens array 25a and a second multi-lens array 25b. The first multi-lens array 25a includes a plurality of lenses 25am. The second multi-lens array 25b includes a plurality of lenses 25bm arranged corresponding to the plurality of lenses 25am.

  The first retardation plate 26a is constituted by, for example, a rotatable half-wave plate. Since the light emitted from the light source device 2 is linearly polarized light, by appropriately setting the rotation angle of the first phase difference plate 26a, the light incident on the first phase difference plate 26a is converted into S-polarized light with respect to the PBS 27. The light can be converted into light containing a component and a P-polarized light component at a predetermined ratio. By changing the rotation angle of the first retardation plate 26a, the ratio of the S-polarized component and the P-polarized component can be changed.

  The PBS 27 is disposed at an angle of 45 ° with respect to the optical axis AX0 and the optical axis AX1. The PBS 27 reflects the S-polarized component of the incident light and transmits the P-polarized component of the incident light. The S-polarized component is reflected by the PBS 27 and travels toward the phosphor wheel 29. The P-polarized light component passes through the PBS 27 and travels toward the rotary diffusing element 42.

  The S-polarized light beam BLs emitted from the PBS 27 is incident on the first pickup optical system 28. The first pickup optical system 28 collects the light beam BLs toward the phosphor layer 47 on the phosphor wheel 29. The first pickup optical system 28 includes a first pickup lens 28a and a second pickup lens 28b.

  The light emitted from the first pickup optical system 28 enters the phosphor layer 47 on the phosphor wheel 29. The phosphor wheel 29 is a reflection-type rotating fluorescent plate, and is provided between the phosphor layer 47 that emits fluorescent light, the rotating plate 49 that supports the phosphor layer 47, and the phosphor layer 47 and the rotating plate 49. A reflection film (not shown) for reflecting the fluorescent light, and a drive motor 50 for driving the rotating plate 49. Since the phosphor wheel 29 includes a reflective film, it emits fluorescent light toward the PBS 27. For example, a disc is used as the rotating plate 49, but the shape of the rotating plate 49 is not limited to a disc, and may be a flat plate.

  The phosphor layer 47 includes a plurality of phosphor particles that absorb the light beam BLs, convert it into yellow fluorescent light, and emit it. As the phosphor particles, for example, YAG (yttrium, aluminum, garnet) phosphors can be used. The plurality of phosphor particles may be composed of one type of particle, or may be composed of a plurality of types of particles having different formation materials.

  On the other hand, the P-polarized light beam BLp emitted from the PBS 27 is incident on the second retardation plate 26b. The second retardation plate 26b is a quarter wavelength plate. The light beam BLp is converted into circularly polarized light by passing through the second retardation plate 26b. The light beam BLp that has passed through the second phase difference plate 26 b is incident on the second pickup optical system 41. The second pickup optical system 41 condenses the light beam BLp toward the rotary diffusing element 42. The second pickup optical system 41 is composed of a first pickup lens 41a and a second pickup lens 41b.

  The rotary diffusion element 42 includes a diffuse reflection plate 52 and a drive motor 53 for rotating the diffusion reflection plate 52. The diffuse reflector 52 diffusely reflects the circularly polarized light beam BLp emitted from the second pickup optical system 41 toward the PBS 27. The diffusive reflector 52 preferably causes Lambertian reflection of the light beam BLp incident on the diffusive reflector 52. The rotation axis of the drive motor 53 is disposed substantially parallel to the optical axis AX0. Thereby, the diffuse reflection plate 52 can be rotated in a plane intersecting the optical axis of the light incident on the diffuse reflection plate 52. The diffuse reflection plate 52 is formed, for example, in a circular shape when viewed from the direction of the rotation axis, but the shape of the diffuse reflection plate 52 is not limited to a circular plate, and may be a flat plate.

  The circularly polarized light beam BLp reflected by the diffusive reflecting plate 52 and transmitted again through the second pickup optical system 41 is transmitted through the second retardation plate 26b again and becomes an S-polarized light beam.

  The yellow fluorescent light emitted from the phosphor layer 47 and the blue S-polarized light beam BLp emitted from the rotary diffusing element 42 are combined by the PBS 27 to become white illumination light WL. The illumination light WL is incident on the uniform illumination optical system 40 shown in FIG.

(Light source device)
FIG. 3 is a plan view of the light source device 2 of the present embodiment. 4 is a cross-sectional view taken along line IV-IV in FIG.
As shown in FIGS. 3 and 4, the light source device 2 includes a light emitting unit 21 and a collimating optical system 22. The light emitting unit 21 includes a substrate 210, a plurality of submounts 211, a plurality of light emitting elements 212, a frame 213, and a translucent member 214. The collimating optical system 22 includes a plurality of collimating lenses 220.

  An accommodation space S surrounded by the substrate 210, the frame 213, and the translucent member 214 is provided on the first surface 210 a side of the substrate 210. The plurality of light emitting elements 212 are housed in a sealed housing space S. That is, the light source device 2 of the present embodiment has a form in which a plurality of light emitting elements 212 are accommodated in one common package.

  In the following description, the arrangement direction of the plurality of submounts 211 is the X direction, the extending direction of each submount 211 is the Y direction, and the direction orthogonal to the X direction and the Y direction is the Z direction. The X direction in the present embodiment corresponds to the first direction in the claims. The Z direction of the present embodiment corresponds to the second direction of the claims.

The substrate 210 is a plate-like member having a first surface 210a and a second surface 210b opposite to the first surface 210a. The shape of the substrate 210 is a rectangular shape in plan view as viewed from the surface normal direction of the first surface 210a. A plurality of light emitting elements 212 are provided on the first surface 210 a of the substrate 210 via a plurality of submounts 211. On the second surface 210b of the substrate 210, a heat radiator (not shown) for releasing heat generated from the plurality of light emitting elements 212 is appropriately provided. Therefore, the substrate 210 is made of a metal material having a high thermal conductivity. As this kind of metal material, copper, aluminum and the like are preferably used, and copper is particularly preferably used.
Hereinafter, when simply referred to as “plan view”, it means a plan view when viewed from the surface normal direction of the first surface 210 a of the substrate 210.

  The plurality of submounts 211 are provided on the first surface 210a of the substrate 210 at a predetermined interval in the X direction. Each submount 211 is provided on the first surface 210 a of the substrate 210 so as to extend in the Y direction. Each submount 211 has a trapezoidal shape in the XZ cross section, and has an inclined surface 211c and a bottom surface 211b. The angle formed between the inclined surface 211c and the bottom surface 211b is larger than 0 ° and smaller than 90 °.

  As shown in FIG. 3, in the present embodiment, four light emitting elements 212 are provided on the inclined surface 211 c of one submount 211. However, one light emitting element 212 may be mounted on one submount 211. The number of light emitting elements 212 mounted on one submount 211 can be set as appropriate.

  The submount 211 is made of a ceramic material such as aluminum nitride or alumina. The submount 211 is interposed between the substrate 210 and the light emitting element 212 and relieves stress caused by a difference in linear expansion coefficient between the substrate 210 and the light emitting element 212. The submount 211 is joined to the substrate 210 by a joining material (not shown) such as silver solder or gold-tin solder.

The light emitting element 212 is configured by a solid light source such as a semiconductor laser or a light emitting diode. The light-emitting element 212 may be a light-emitting element having an arbitrary wavelength depending on the application of the light source device 2. In the present embodiment, as the light emitting element 212 that emits blue light having a wavelength of 430 nm to 490 nm for phosphor excitation, for example, a nitride-based semiconductor (In _X Al _Y Ga _1- XYN, 0 ≦ X ≦ 1, 0 An edge-emitting semiconductor laser constituted by ≦ Y ≦ 1, X + Y ≦ 1) is used. Further, in addition to the above general formula, a group III element partially substituted with a boron atom or a group V element partially substituted with a phosphorus atom or an arsenic atom may be included. .

  As shown in FIG. 3, the plurality of light emitting elements 212 includes, for example, (m × n) (m, n: a natural number of 2 or more) semiconductor lasers in a lattice shape of m rows and n columns in the X direction and the Y direction. It has the structure arranged in. In the present embodiment, as the plurality of light emitting elements 212, for example, 16 semiconductor lasers are arranged in a lattice pattern of 4 rows and 4 columns. Hereinafter, for convenience of explanation, among the four light emitting elements shown in FIG. 4, the leftmost light emitting element 212 is referred to as a first light emitting element 212A, and the right light emitting element 212 is referred to as a second light emitting element 212B. That is, the light emitting unit 21 includes a first light emitting element 212A and a second light emitting element 212B arranged in the X direction.

  An axis passing through the centers of the plurality of light emitting elements 212 arranged in a lattice and parallel to the Z direction is defined as an optical axis AX0. The plurality of light emitting elements 212 are provided in plane symmetry with respect to a plane FA including the optical axis AX0 and perpendicular to the X direction.

  The light emitting element 212 includes a light emitting surface 212d that emits light and a supported surface 212e. The area of the supported surface 212e is larger than the area of the light emitting surface 212d. The light emitting element 212 is fixed to the submount 211 so that the light emission surface 212d faces the opposite side of the first surface 210a of the substrate 210 and the supported surface 212e faces the inclined surface 211c of the submount 211. The light emitting element 211 is joined to the submount 211 by a joining material (not shown) such as silver solder or gold-tin solder.

  The light emitting unit 21 is configured to emit light emitted from each light emitting element 212 in a direction inclined from the Z direction by providing each light emitting element 212 on the inclined surface 211c of the submount 211. . In other words, the light emitted from the light emitting element 212 is emitted from the light emitting unit 21 at an angle larger than 0 ° and smaller than 90 ° with respect to a plane perpendicular to the first direction. Moreover, the light emission directions from the plurality of light emitting elements 212 are parallel to each other. That is, the light emitting unit 21 emits the first light emitted from the first light emitting element 212A in the first emission direction (third direction) inclined from the Z direction, and is emitted from the second light emitting element 212B. The second light is emitted in a second emission direction (fourth direction) inclined from the Z direction. The first injection direction is parallel to the second injection direction.

  The frame 213 is provided on the first surface 210 a side of the substrate 210 so as to surround the plurality of light emitting elements 212. The frame 213 has a rectangular annular shape in plan view. The frame 213 may be a member in which all four sides of the rectangle are integrated, or a part of the frame 213 may be formed by joining separate members. The frame 213 keeps the distance between the substrate 210 and the translucent member 214 constant and defines an accommodation space S in which the plurality of light emitting elements 212 are accommodated. For this reason, the frame 213 preferably has a predetermined rigidity. The frame 213 is bonded to the first surface 210a of the substrate 210 via a bonding material (not shown) such as silver solder or gold-tin solder.

  The frame 213 serves to relieve stress generated in the translucent member 214. Therefore, the frame 213 is preferably made of a material having a linear expansion coefficient between the linear expansion coefficient of the substrate 210 and the linear expansion coefficient of the translucent member 214. As the material of the frame 213, for example, a ceramic material such as alumina, silicon carbide, or silicon nitride is preferably used, and alumina is particularly preferably used.

  The translucent member 214 is a plate member having light transmissivity. The planar shape of the translucent member 214 is a rectangular shape. The translucent member 214 is provided on the frame 213 and transmits the light emitted from the light emitting element 212. Therefore, as a material for the light transmissive member 214, a light transmissive material having a high light transmittance is preferably used. As a specific example of the translucent member 214, for example, borosilicate glass such as BK7, optical glass including quartz glass, synthetic quartz glass, crystal, sapphire, and the like are used. The translucent member 214 is joined to the frame 213 via a joining material (not shown) such as a solder material or low-melting glass.

  By housing the light emitting element 212 in the housing space S, adhesion of foreign substances such as organic substances and moisture to the light emitting element 212 is reduced. The storage space S is preferably in a reduced pressure state. Alternatively, the storage space S may be filled with an inert gas such as nitrogen gas or dry air. Note that the reduced pressure state is a state of a space filled with a gas having a pressure lower than the atmospheric pressure. In the reduced pressure state, the gas filled in the accommodation space S is preferably an inert gas or dry air.

  Each of the plurality of collimating lenses 220 is provided corresponding to each of the plurality of light emitting elements 212. The light emitted from each light emitting element 212 is incident on each collimator lens 220 corresponding to the light emitting element 212. In the present embodiment, the collimating lens 220 is constituted by a plano-convex lens, and has one flat incident surface 220a and one lens surface 220b made of a convex surface. The collimating lens 220 is arranged in such a direction that light enters from the incident surface 220a and exits from the lens surface 220b.

  Each collimator lens 220 is provided such that the principal ray BL of the light emitted from the light emitting element 212 is deviated from the optical axis CX of the collimator lens 220. Further, the incident angle of the principal ray BL with respect to the lens surface 220b is larger than 0 ° and smaller than 90 °. Thereby, the principal ray BL is refracted by the lens surface 220b. In the present embodiment, the chief ray BL is emitted from the light source device 2 in a substantially Z direction. Hereinafter, for convenience of explanation, among the four collimating lenses 220 shown in FIG. 4, the collimating lens 220 corresponding to the first light emitting element 212A is referred to as a first collimating optical system 220A and corresponds to the second light emitting element 212B. The collimated lens 220 is referred to as a second collimating optical system 220B.

  That is, in the first collimating optical system 220A, the angle β1b formed between the principal ray BL of the first light emitted from the first collimating optical system 220A and the Z direction indicated by the straight line Lz is the first collimating optical system. It is arranged so as to be smaller than an angle β1a formed by the principal ray BL of the first light before entering 220A and the Z direction indicated by the straight line Lz. Further, in the second collimating optical system 220B, an angle β2b formed between the principal ray BL of the second light emitted from the second collimating optical system 220B and the Z direction is incident on the second collimating optical system 220B. It is arranged so as to be smaller than the angle β2a formed by the principal ray BL of the previous second light and the Z direction. The angle β1b and the angle β2b are preferably 0 °, but may not necessarily be 0 ° and may be set as appropriate. In the present embodiment, as shown in FIG. 4, the angle β1b and the angle β2b are 0 °.

  As described above, a plane that includes the first light-emitting element 212A and the second light-emitting element 212B and that is perpendicular to the second direction is referred to as a light-emitting element array surface F1. The light emitting surface 212d of the light emitting element 212 is included. The array plane F1 is parallel to the XY plane. Further, a plane that includes the first collimating optical system 220A and the second collimating optical system 220B and that is perpendicular to the second direction is referred to as an arrangement surface F2 of the collimating optical system. The principal point of the collimating lens 220 is included. The array surface F1 and the array surface F2 are parallel to each other.

Hereinafter, the operation and effect of the light source device 2 of the present embodiment will be described.
FIG. 5 is a schematic diagram showing the positional relationship between the light emitting element 1002 and the light source image 1005 in the conventional light source device 1001. For convenience, a pair of light emitting elements 1002 and a collimator lens 1003 are shown. Actually, like the light source device 2, the light source device 1001 is also 16 semiconductor lasers arranged in a 4 × 4 grid. It has. Similarly to the light source device 2, the light emitting element array surface F1a and the collimator optical system array surface F2a are defined. Note that the value of the interval La between the array surface F1a and the array surface F2a is equal to the value of the interval L between the array surface F1 and the array surface F2.

  FIG. 6 is a schematic diagram showing a positional relationship between the light emitting element 212 and the light source image 105 in the light source device 2 of the present embodiment. For convenience, a set of light emitting elements 212 and a collimating lens 220 are shown. In each of FIGS. 5 and 6, the collimating optical system and the first pickup among the elements arranged in the optical path between the light source image formed on the phosphor layer 47 and the light emitting element, for example, Illustration of elements other than the optical system is omitted. For convenience, the first pickup optical system is replaced with one condenser lens.

  As shown in FIG. 5, the light emitting element 1002 emits light in a direction perpendicular to the array surface F1a. Further, the positional relationship between the collimating lens 1003 and the light emitting element 1002 is designed so that the optical axis CXa of the collimating lens 1003 coincides with the principal ray BL of the light emitted from the light emitting element 1002.

  In the following description, it is assumed that the mounting position of the light emitting element 1002 has shifted from the predetermined position in the X direction. In this case, the light source image 1005 is also shifted from the predetermined position in the X direction. The shift amount (mounting error) of the light emitting element 1002 is x1, and the shift amount of the light source image 1005 is x2. Further, the distance from the light emitting surface 1002a of the light emitting element 1002 to the principal point CP1a of the collimating lens 1003, that is, the value of the interval La is L1. That is, the focal length of the collimating lens 1003 is L1. The distance from the principal point CP2 of the condenser lens 1004 to the light source image 1005 is L2.

Equation (1) is derived from the imaging formula.
x1: L1 = x2: L2 (1)
From the equation (1), the shift amount x2 of the light source image 1005 is expressed by the equation (2).
x2 = (L2 / L1) × x1 (2)

  On the other hand, as shown in FIG. 6, in the light source device 2 of the present embodiment, the light emitting element 212 emits light in a direction inclined by an angle β (0 ° <β <90 °) from the direction perpendicular to the array plane F1. Is injected.

  The positional relationship between the collimating lens 220 and the light emitting element 212 is designed such that the optical axis CX of the collimating lens 220 is shifted from the principal ray BL of the light emitted from the light emitting element 212 by a predetermined amount in a predetermined direction. Yes. The value of the distance L is L1, and the focal length of the collimating lens 220 is L3. Therefore, the focal length L3 of the collimating lens 220 is larger than the focal length L1 of the collimating lens 1003.

  When the mounting position of the light emitting element 212 is shifted from the predetermined position in the X direction, the light source image 105 is also shifted from the predetermined position in the X direction. The shift amount (mounting error) of the light emitting element 212 is x1, and the shift amount of the light source image 105 is x3. Further, the distance from the light emitting surface 212a of the light emitting element 212 to the principal point CP1 of the collimating lens 220 is L3, and the distance from the principal point CP2 of the condenser lens 104 to the light source image 105 is L2.

Equation (3) is derived from the imaging formula.
x1: L3 = x3: L2 (3)
From the equation (3), the shift amount x3 of the light source image 105 is represented by the equation (4).
x3 = (L2 / L3) × x1 (4)
Here, when the equation (4) is rewritten using L3 = L1 / cos β, the equation (5) is obtained.
x3 = (L2 / L1) × x1 × cosβ (5)
From the equations (2) and (5),
x3 = x2 × cosβ (5)

  As described above, according to the light source device 2 of the present embodiment, the light emission direction of the light source image accompanying the positional deviation of the light emitting element 212 is obtained by inclining the light emission direction from the light emitting unit 21 by the angle β from the second direction. The deviation amount can be set to cos β times the conventional deviation amount. In other words, in the light source device 2 of the present embodiment, even if the light emitting element 212 is misaligned, the amount of misalignment of the light source image accompanying the misalignment of the light emitting element 212 can be made smaller than in the past. As described above, the light source device 2 having a large tolerance for the relative relationship between the principal ray BL, that is, the optical axis of the light emitting element 212 and the optical axis CX of the collimating lens 220 corresponding to the light emitting element 212 can be provided. .

  Thereby, in the illuminating device 70 of this embodiment, since the light source image 105 is hard to shift | deviate from a predetermined position on the fluorescent substance layer 47, it cannot utilize in the latter stage optical system among the fluorescent light inject | emitted from the fluorescent substance layer 47. The generation of components is reduced compared to conventional lighting devices. Moreover, since the projector 1 of this embodiment is provided with said illuminating device 70, it is excellent in light utilization efficiency.

  Further, in the light source device 2 of the present embodiment, since the light emission directions from the plurality of light emitting elements 212 are parallel to each other, the pitch in the X direction of each principal ray BL in the subsequent stage of the collimating optical system 22 is the same as the prior art. Similarly, the pitch of the light emitting elements 212 in the X direction can be made substantially equal. If the angle between the principal ray BL and the Z direction in the subsequent stage of the collimating optical system 22 is set to 0 ° with respect to all the light emitting elements 212, an optical system having the same size as the conventional one is arranged in the subsequent stage of the collimating optical system 22. can do. On the other hand, the angle formed between the principal ray BL and the Z direction in the rear stage of the collimating optical system 22 is set to 0 within a range in which the light emitted from each light emitting element 212 cannot be applied to the collimating lens 220 not corresponding to the light emitting element 212. If it is set to a value larger than 0 °, the pitch on the XZ plane of each principal ray BL in the subsequent stage of the collimating optical system 22 is shorter than the pitch in the X direction of the light emitting element 212. It can arrange | position in the back | latter stage of 22.

[Second Embodiment]
Hereinafter, a second embodiment of the present invention will be described with reference to FIGS.
The configuration of the projector and the illumination device of the second embodiment is the same as that of the first embodiment, and the configuration of the light source device 12 is different from that of the light source device 2 of the first embodiment. Therefore, descriptions of the projector and the lighting device are omitted, and only the light source device 12 is described.
FIG. 7 is a plan view of the light source device 12 of the present embodiment. FIG. 8 is a cross-sectional view perpendicular to the Y direction of the light source device 12 of the present embodiment, and is a cross-sectional view taken along the line VIII-VIII in FIG. 9 is a cross-sectional view perpendicular to the X direction of the light source device 12 of the present embodiment, and is a cross-sectional view taken along the line IX-IX in FIG.
7-9, the same code | symbol is attached | subjected to the same component as drawing used in 1st Embodiment, and description is abbreviate | omitted.

  As shown in FIGS. 7 to 9, the light source device 12 includes a light emitting unit 23 and a collimating optical system 35. The light emitting unit 23 includes a substrate 210, a plurality of submounts 215, a plurality of light emitting elements 212, and a plurality of prisms 216. The collimating optical system 35 includes a first cylindrical lens array 35A and a second cylindrical lens array 35B. As shown in FIG. 8, in the light source device 12, the light emitting element 212 is provided such that the supported surface 212 e is in contact with the upper surface 215 a of the submount 215, and emits light in the −X direction or the + X direction.

  In FIG. 8, the two light emitting elements 212 on the left side of the optical axis AX0 parallel to the Z direction and the two light emitting elements 212 on the right side of the optical axis AX0 have light emission directions opposite to each other. That is, the two left light emitting elements 212 are arranged such that the light emission surface 212d faces the −X direction, and emits light in the −X direction. The two right light emitting elements 212 are arranged such that the light emission surface 212d faces the + X direction, and emits light in the + X direction.

  As shown in FIG. 7, also in the present embodiment, as in the first embodiment, the plurality of light emitting elements 212 are arranged in a lattice pattern in the X direction and the Y direction. The plurality of light emitting elements 212 are provided in plane symmetry with respect to a plane FA including the optical axis AX0 and perpendicular to the X direction.

  The prism 216 is provided on the optical path of the light emitted from the light emitting element 212 corresponding to the prism 216. The prism 216 has a triangular cross-section cut along a plane (XZ plane) parallel to the light emission direction of the light emitting element 212 and perpendicular to the first surface 210a of the substrate 210. The prism 216 includes an incident surface 216 a on which light emitted from each light emitting element 212 is incident, and a reflective surface 216 c that reflects the light in a direction intersecting the first surface 210 a of the substrate 210.

  The reflection surface 216c is inclined with respect to the first surface 210a of the substrate 210, and an angle (inclination angle α) formed between the reflection surface 216c and the first surface 210a is larger than 0 ° and smaller than 45 °. By setting the inclination angle α of the reflection surface 216c in this way, the light incident on the prism 216 from the light emitting element 212 is emitted from the light emitting unit 23 in a direction inclined from the Z direction.

  In the case of the present embodiment, in FIG. 8, the two light emitting elements 212 on the left side and the two light emitting elements 212 on the right side have opposite inclination directions with respect to the Z direction of the principal ray BL emitted from the light emitting unit 23. That is, when the angle viewed clockwise from the Z direction is defined as a positive angle when viewed from the Y direction, the inclination angle of the principal ray BL emitted from the light emitting unit 23 is determined in the two right light emitting elements 212. Is positive (+ θ), and in the two light emitting elements 212 on the left side, the inclination angle of the principal ray BL emitted from the light emitting unit 23 is negative (−θ).

  In the present embodiment, the prism 216 is joined to the surface of the translucent member 214 on the accommodation space S side. However, the prism 216 is not necessarily bonded to the translucent member 214.

  As shown in FIGS. 7 and 9, one common prism 216 is provided corresponding to the four light emitting elements 212 arranged in the Y direction. Therefore, each light emitted from the four light emitting elements 212 arranged in the Y direction is reflected by the reflecting surface 216c of one prism 216. However, only one light emitting element 212 may correspond to one prism 216. The number of light emitting elements 212 corresponding to one prism 216 can be set as appropriate.

  Hereinafter, for convenience of explanation, among the four light emitting elements 212 shown in FIG. 8, the second light emitting element 212 from the left is referred to as a first light emitting element 212A, and the light emitting element 212 on the right is the second light emitting element. This is referred to as 212B. The prism 216 corresponding to the first light emitting element 212A is referred to as a first prism 216A, and the prism 216 corresponding to the second light emitting element 212B is referred to as a second prism 216B. The reflecting surface of the first prism 216A is referred to as a first reflecting surface 216cA, and the reflecting surface of the second prism 216B is referred to as a second reflecting surface 216cB. That is, the light emitting unit 23 includes a first light emitting element 212A and a second light emitting element 212B arranged in the X direction. The first light is emitted from the first light emitting element 212A substantially in parallel with the −X direction, and reflected by the first reflecting surface 216cA in the first emission direction (third direction). The second light is emitted from the second light emitting element 212B substantially parallel to the + X direction, and reflected by the second reflecting surface 216cB in the second emission direction (fourth direction).

  The light emitted from the light emitting unit 23 passes through the first cylindrical lens array 35A and the second cylindrical lens array 35B in this order. The first cylindrical lens array 35A includes a plurality of first cylindrical lenses 351. The second cylindrical lens array 35B includes a plurality of second cylindrical lenses 352.

  The first cylindrical lens 351 has one flat incident surface 351a and one lens surface 351b made of a convex surface. The second cylindrical lens 352 has a flat incident surface 352a and a convex lens surface 352b. The first cylindrical lens 351 has a refractive power in the XZ plane and does not have a refractive power in the YZ plane. The second cylindrical lens 352 has a refractive power in the YZ plane and does not have a refractive power in the XZ plane.

  Similar to the first embodiment, an array surface F1 of the light emitting elements is defined. The array plane F1 is parallel to the XY plane. The direction of the generatrix of the first cylindrical lens 351 and the direction of the generatrix of the second cylindrical lens 352 are orthogonal to each other and parallel to the array plane F1.

  The first cylindrical lens 351 is provided to be inclined with respect to the array surface F1 so that the principal ray BL emitted from the light emitting unit 23 is incident perpendicularly to the incident surface 351a. The first cylindrical lens 351 is provided so that the principal ray BL does not pass through the top of the first cylindrical lens 351. As a result, the principal ray BL emitted from the light emitting unit 23 is refracted by the lens surface 351b of the first cylindrical lens 351. In the present embodiment, the chief ray BL is emitted substantially in the Z direction.

  As indicated by the rightmost light emitting element 212 in FIG. 8, the light emitted from the light emitting element 212 in the X direction has a beam shape in which the divergence angle in the XZ plane is larger than the divergence angle in the XY plane. Therefore, it is desirable that the light emitted from the light emitting element 212 is collimated in the XZ plane by the first cylindrical lens 351 located on the side close to the light emitting element.

  On the other hand, as shown in FIG. 9, when viewed from the X direction, the second cylindrical lens 352 is configured so that the principal ray BL transmitted through the first cylindrical lens 351 is perpendicularly incident on the incident surface 352a. The incident surface 352a is provided so as to be parallel to the array surface F1. The second cylindrical lens 352 is provided so that the chief ray BL passes through the top of the second cylindrical lens 352. As a result, the principal ray BL transmitted through the first cylindrical lens 351 travels straight without being refracted by the second cylindrical lens 352.

  Hereinafter, for convenience of explanation, as shown in FIG. 7, an intersection corresponding to the first light emitting element 212 </ b> A among the intersections of the first cylindrical lens 351 and the second cylindrical lens 352 when viewed from the Z direction. This part is referred to as a first collimating optical system 35AA. In other words, the first collimating optical system 35AA includes a portion corresponding to the first light emitting element 212A in the first cylindrical lens 351 and a portion corresponding to the first light emitting element 212A in the second cylindrical lens 352. And a pair. Similarly, the intersection corresponding to the second light emitting element 212B among the intersections of the first cylindrical lens 351 and the second cylindrical lens 352 is referred to as a second collimating optical system 35BB.

  In the present embodiment, the first collimating optical system 35AA has an angle formed between the principal ray BL of the first light emitted from the first collimating optical system 35AA and the Z direction in the first collimating optical system 35AA. It is arranged so as to be smaller than the angle formed between the principal ray BL of the first light before entering and the Z direction. The second collimating optical system 35BB has a second angle before the angle formed between the principal ray BL of the second light emitted from the second collimating optical system 35BB and the Z direction is incident on the second collimating optical system 35BB. Are arranged so as to be smaller than the angle formed between the principal ray BL of the light and the Z direction. Further, when viewed from a direction perpendicular to the Z direction (second direction) and the first injection direction (third direction), the Z direction is between the first injection direction and the second injection direction (fourth direction). positioned.

  Also in this embodiment, the light emission direction from the light emitting unit 23 is inclined by the angle + θ or −θ with respect to the second direction, so that the optical axis of the light emitting element 212 and the collimating optical system corresponding to the light emitting element 212 are obtained. The same effect as that of the first embodiment in which the light source device 12 having a larger tolerance than the conventional light source device can be provided. Specifically, the allowable error with respect to the relative relationship between the light emitting element 212 and the prism 216 in the Z direction is larger than the conventional one.

  Further, in the light source device 12 of the present embodiment, the principal ray BL of the light emitted from the light emitting element 212 in the −X direction or the + X direction is reflected by the prism 216, so that the light is emitted from the light emitting unit 23. The direction can be adjusted by the inclination angle of the reflecting surface 216c of the prism 216. Therefore, for example, it is not necessary to provide an inclined surface on the submount as in the first embodiment. Thereby, the structure of the submount 215 can be simplified, and manufacture of the light source device 12 becomes easy.

  In the light source device 12 of the present embodiment, since the light emitting element 212 is provided on the upper surface 215a of the submount 215, the height (size in the Z direction) of the submount 215 is larger than that of the submount 211 of the first embodiment. Can also be lowered. Therefore, the heat of the light emitting element 212 is easily transferred to the substrate 210 via the submount 215, and the heat dissipation of the light emitting element 212 can be improved as compared with the first embodiment. Accordingly, the light emission efficiency of the light emitting element 212 can be increased.

  Further, in the light source device 12 of the present embodiment, the first light emitting element 212A and the second light emitting element 212B have the opposite tilt directions with respect to the Z direction of the principal ray BL emitted from the light emitting unit 23. The light beam after exiting the optical system 35 has a highly symmetrical intensity distribution around the optical axis AX0. Therefore, the light source device 12 is suitable for an optical system that requires a highly symmetrical intensity distribution. Examples of optical systems that require a highly symmetrical intensity distribution include the following.

  For example, when a plurality of lights (excitation light) are superimposed on the phosphor layer 47 as in this embodiment, the bias distribution of the excitation light intensity can be reduced, and the illuminance distribution on the phosphor layer 47 is averaged. be able to. As a result, the luminous efficiency of the phosphor layer 47 can be increased.

  Alternatively, when a plurality of lights are superimposed on the diffuse reflector 52, the illuminance distribution on the diffuse reflector 52 can be averaged. As a result, an object to be illuminated such as a light modulation device can be illuminated uniformly. Alternatively, when the light source device 12 is used as an illuminating device that directly illuminates an object to be illuminated, such as a light modulation device, unevenness in intensity distribution can be reduced, so that illuminance unevenness, color unevenness, and the like can be reduced.

[Third Embodiment]
Hereinafter, a third embodiment of the present invention will be described with reference to FIGS.
The configuration of the projector and the illumination device of the third embodiment is the same as that of the first embodiment, and the configuration of the light source device 62 is different from that of the light source device 2 of the first embodiment. Therefore, descriptions of the projector and the lighting device are omitted, and only the light source device 62 is described.
FIG. 10 is a cross-sectional view perpendicular to the Y direction of the light source device 62 of the present embodiment. 11 is a cross-sectional view perpendicular to the X direction of the light source device 62 of the present embodiment, and is a cross-sectional view taken along the line XI-XI in FIG. FIG. 12 is a perspective view showing a collimating optical system in the light source device 62 of the present embodiment.
10-12, the same code | symbol is attached | subjected to the same component as drawing used in 1st Embodiment, and description is abbreviate | omitted.

  As shown in FIGS. 10 to 12, in the light source device 62 of the present embodiment, the configuration of the light emitting unit 23 is the same as that of the light emitting unit 23 of the second embodiment, and the configuration of the collimating optical system 63 is the same as that of the second embodiment. Different from the collimating optical system 35.

  The collimating optical system 63 includes a first cylindrical lens array 63A and a second cylindrical lens array 63B. The first cylindrical lens array 63A includes a plurality of first cylindrical lenses 631. The second cylindrical lens array 63B includes a plurality of second cylindrical lenses 632.

  The first cylindrical lens 631 has a flat incident surface 631a and a convex lens surface 631b. The second cylindrical lens 632 has one flat incident surface 632a and one lens surface 632b made of a convex surface. The first cylindrical lens 631 has refractive power in the XZ plane and does not have refractive power in the YZ plane. The second cylindrical lens 632 has a refractive power in the YZ plane and does not have a refractive power in the XZ plane.

  Similar to the second embodiment, an array surface F1 of the light emitting elements is defined. The array plane F1 is parallel to the XY plane. The direction of the generatrix of the first cylindrical lens 631 and the direction of the generatrix of the second cylindrical lens 632 are orthogonal to each other. The generatrix of the first cylindrical lens 631 is parallel to the array plane F1, but the generatrix of the second cylindrical lens 632 is inclined with respect to the array plane F1.

  The first cylindrical lens 631 is provided to be inclined with respect to the arrangement surface F1 so that the principal ray BL emitted from the light emitting unit 23 is incident on the incidence surface 631a perpendicularly. The first cylindrical lens 631 is provided so that the principal ray BL passes through the top of the first cylindrical lens 631. Thereby, the chief ray BL emitted from the light emitting unit 23 goes straight without being refracted by the first cylindrical lens 631.

  On the other hand, as shown in FIGS. 10 and 12, the second cylindrical lens 632 is formed such that the incident surface 632a and the generatrix of the second cylindrical lens 632 are non-parallel when viewed from the Y direction. . As shown in FIG. 11, when viewed from the X direction, the principal ray BL transmitted through the first cylindrical lens 631 enters perpendicularly to the incident surface 632 a and passes through the top of the second cylindrical lens 632. . When viewed from the Y direction, the second cylindrical lens 632 is configured such that the principal ray BL emitted from the first cylindrical lens 631 is incident on the incident surface 632a at an incident angle other than 0 °. Are provided in a state inclined from the arrangement surface F1. As a result, the principal ray BL is refracted at each of the incident surface 632a and the lens surface 632b on the XZ plane, and is emitted substantially in the Z direction. As described above, in the present embodiment, the principal ray BL emitted from the light emitting unit 23 is refracted by the second cylindrical lens 632.

  Also in the present embodiment, the light emission direction from the light emitting unit 23 is inclined by the angle + θ or −θ with respect to the second direction, so that the relative relationship between the optical axis of the light emitting element 212 and the collimating optical system 63 is increased. The same effect as the first and second embodiments that the light source device 62 having a larger allowable error than the conventional one can be provided.

  Also in the present embodiment, the configuration of the submount 215 can be simplified by using the prism 216, and the luminous efficiency of the light emitting element 212 can be improved by increasing the heat dissipation of the light emitting element 212. The same effects as in the second embodiment, such as being suitable for an optical system that requires distribution, can be obtained.

[Fourth Embodiment]
Hereinafter, a fourth embodiment of the present invention will be described with reference to FIGS.
The configuration of the projector and the illumination device of the fourth embodiment is the same as that of the first embodiment, and the configuration of the light source device 72 is different from that of the light source device 2 of the first embodiment. Therefore, descriptions of the projector and the lighting device are omitted, and only the light source device 72 is described.
13 to 15, the same reference numerals are given to the same components as those used in the first embodiment, and the description thereof will be omitted.

FIG. 13 is a plan view of the light source device 72 of the present embodiment. In FIG. 13, the illustration of the light emitting unit 76 is simplified.
The light source device 72 includes a first light source unit 73 that emits a plurality of lights, a second light source unit 74 that emits a plurality of lights, and a light combining unit 75. The light combining unit 75 combines the plurality of lights emitted from the first light source unit 73 and the plurality of lights emitted from the second light source unit 74. The first light source unit 73 is provided on the optical axis AX0, and emits a plurality of lights in a direction (Z direction) parallel to the optical axis AX0. The second light source unit 74 is provided on the optical axis AX2 orthogonal to the optical axis AX0, and emits a plurality of lights in a direction parallel to the optical axis AX2 (Y direction). The light source device 72 emits the light combined by the light combining unit 75 in the Z direction.
In FIG. 13, the first light source unit 73 and the second light source unit 74 are shown in a simplified manner. Detailed configurations of these light source units will be described in detail below with reference to FIGS. 14 and 15.

  Since the first light source unit 73 and the second light source unit 74 have the same configuration, the configuration of these light source units will be described below by using the first light source unit 73 as a representative. Each of the first light source unit 73 and the second light source unit 74 corresponds to the light source device of the first to third embodiments.

  The first light source unit 73 includes a light emitting unit 76 and a collimating optical system 77.

14 is a cross-sectional view perpendicular to the Y direction of the first light source unit 73, and is a cross-sectional view taken along line XIV-XIV in FIG.
As shown in FIG. 14, the submount 761 has a rectangular shape in the XZ section. Each light emitting element 212 is provided on the upper side surface 761c of each submount 761 corresponding to each light emitting element 212.

15 is a cross-sectional view perpendicular to the X direction of the first light source unit 73, and is a cross-sectional view taken along the line XV-XV in FIG.
As shown in FIG. 15, four light emitting elements 212 are mounted on one submount 761. However, only one light emitting element 212 may be mounted on one submount 761. The number of light emitting elements 212 mounted on one submount 761 can be set as appropriate. The light emitting unit 76 is configured to emit the principal ray BL of the light emitted from each light emitting element 212 in a direction inclined from the Z direction on the YZ plane.

  In the case of the present embodiment, as shown in FIG. 15, when viewed from the direction perpendicular to the YZ plane, the two light emitting elements 212 on the left side and the two light emitting elements 212 on the right side are inclined with respect to the Z direction. Is the opposite.

  Hereinafter, for convenience of explanation, among the four light emitting elements 212 shown in FIG. 15, the second light emitting element 212 from the right is referred to as a first light emitting element 212A, and the second light emitting element 212 from the left is a second light emitting element. This is referred to as an element 212B, and the leftmost light emitting element 212 is referred to as a third light emitting element 212C.

  When viewed from a direction perpendicular to the Z direction and the first emission direction (third direction), the second light emitting element 212B is located between the first light emitting element 212A and the third light emitting element 212C. The light emitting unit 76 emits the principal ray BL of the third light emitted from the third light emitting element 212C in a third emission direction (fifth direction) inclined from the Z direction (second direction). It is configured. The second injection direction (fourth direction) is located between the Z direction and the third injection direction.

Here, an angle formed between the principal ray BL and the Z direction in the optical path between the light emitting unit 76 and the collimating optical system 77 is referred to as an inclination angle of the principal ray BL.
The inclination angle of the principal ray BL of the light emitted from the rightmost light emitting element 212 is θa, the inclination angle of the light emitted from the first light emitting element 212A is θb, and the inclination of the light emitted from the second light emitting element 212B. The angle is θc, and the inclination angle of the light emitted from the third light emitting element 212C is θd. When viewed from the X direction, if clockwise is defined as a positive angle with respect to the Z direction, θa and θb are positive and θc and θd are negative in this embodiment. Further, | θa | = | θd |, | θb | = | θc |, θa> θb. That is, with the plane FA including the optical axis AX0 as a symmetry plane, the tilt angle of the principal ray BL increases as the distance between the symmetry plane and the light emitting element 212 increases.

  The collimating optical system 77 includes a first cylindrical lens array 77A and a second cylindrical lens array 77B. The first cylindrical lens array 77A includes a plurality of first cylindrical lenses 771. The second cylindrical lens array 77B includes a plurality of second cylindrical lenses 772.

  The first cylindrical lens 771 has a flat incident surface 771a and a convex lens surface 771b. The second cylindrical lens 772 has a flat incident surface 772a and a convex lens surface 772b. The first cylindrical lens 771 has refractive power in the XZ plane and does not have refractive power in the YZ plane. The second cylindrical lens 772 has a refractive power in the YZ plane and does not have a refractive power in the XZ plane.

  Similar to the second embodiment, an array surface F1 of the light emitting elements is defined. The array plane F1 is parallel to the XY plane. The direction of the generatrix of the first cylindrical lens 771 and the direction of the generatrix of the second cylindrical lens 772 are orthogonal to each other. The generatrix of the first cylindrical lens 771 is inclined with respect to the array plane F1, but the generatrix of the second cylindrical lens 772 is parallel to the array plane F1.

  The first cylindrical lens 771 is provided so as to be inclined with respect to the array surface F1 so that the principal ray BL emitted from the light emitting unit 76 enters perpendicularly to the incident surface 771a. Further, the first cylindrical lens 771 is provided so that the principal ray BL passes through the top of the first cylindrical lens 771. Accordingly, the principal ray BL emitted from the light emitting unit 76 goes straight without being refracted by the first cylindrical lens 771.

  On the other hand, the second cylindrical lens 772 is provided such that the incident surface 772a is inclined with respect to the arrangement surface F1 so that the principal ray BL emitted from the first cylindrical lens 771 enters perpendicularly to the incident surface 772a. It has been. Of the four second cylindrical lenses 772 shown in FIG. 14, the inclination angle of the incident surface 772a of the two outer cylindrical lenses 772 with respect to the array plane F1 is the two inner second cylindrical lenses. It is larger than the inclination angle of the incident surface 772a of 772 with respect to the arrangement surface F1. Further, the width W1 of the two outer second cylindrical lenses 772 is larger than the width W2 of the two inner second cylindrical lenses 772.

  Of the four first cylindrical lenses 771, the focal lengths of the two outer first cylindrical lenses 771 are longer than the focal lengths of the two inner first cylindrical lenses 771. Further, out of the four second cylindrical lenses 772, the focal lengths of the outer two second cylindrical lenses 772 are longer than the focal lengths of the inner two second cylindrical lenses 772.

  Further, the second cylindrical lens 772 is provided so that the principal ray BL emitted from the first cylindrical lens 771 does not pass through the top of the second cylindrical lens 772. Thus, the principal ray BL emitted from the first cylindrical lens 771 is refracted by the lens surface 772b of the second cylindrical lens 772. In the present embodiment, the chief ray BL is emitted substantially in the Z direction.

  As illustrated in FIG. 13, the light combining unit 75 is configured by a plate provided on the optical path of the plurality of lights emitted from the first light source unit 73 and the plurality of lights emitted from the second light source unit 74. It is configured. The light combining unit 75 is disposed such that the surface normal direction of the light combining unit 75 forms an angle of 45 ° with respect to the optical axis AX0 and the optical axis AX2.

  The light combining unit 75 includes a plurality of reflection regions 75R and a plurality of light transmission regions 75T. As seen from the surface normal direction of the light combining unit 75, the reflection regions 75R and the light transmission regions 75T are alternately arranged. The photosynthetic unit 75 can be manufactured by punching a metal plate having a reflective film formed on one surface, for example. The light transmission region 75T transmits a plurality of lights emitted from the first light source unit 73 in the Z direction, and the reflection region 75R reflects the plurality of lights emitted from the second light source unit 74 in the Z direction. . In this way, the light combining unit 75 generates combined light and emits it in the Z direction.

  Also in the present embodiment, since the light emission direction from the light emitting unit 76 is inclined with respect to the optical axis AX0, the same effect as in the first embodiment can be obtained.

  In the case where the light emission directions from the respective light emitting elements 212 are distributed, it is conceivable that the respective light emitting elements 212 are mounted on the side surfaces 761c of the submount 761 in different directions as in the present embodiment. In this case, since there is no member that regulates the inclination angle of the light emitting element 212, an error in the inclination angle of the light emitting element 212 tends to increase. However, according to the configuration of the present embodiment, the tolerance for mounting the light emitting element 212 can be increased.

  The width W31 of the light transmission region 75T when the light combining unit 75 is viewed from the direction parallel to the optical axis AX0 is desirably equal to or greater than the width D31 in the Y direction of the light to be transmitted through the light transmission region 75T. Further, it is desirable that the width W32 of the reflection region 75R when the light combining unit 75 is viewed from the direction parallel to the optical axis AX2 is equal to or larger than the width D32 of the light to be reflected by the reflection region 75R in the Z direction. The reason is as follows. When the width D32 is larger than the width W32, part of the light that should be reflected by the reflection region 75R is transmitted through the light transmission region 75T and does not advance in the direction of emission of the combined light flux. When the width D31 is larger than the width W31, part of the light that should be transmitted through the light transmission region 75T is reflected by the reflection region 75R and does not advance in the direction of emission of the combined light flux. As a result, light loss occurs. However, in order to reduce the light loss, it is necessary to increase the arrangement pitch of the light emitting elements 212 in the first light source unit 73 and the second light source unit 74. This causes a problem that the respective light source units 73 and 74 are enlarged.

  To solve the above problem, in the light source device 72 of the present embodiment, as shown in FIG. 13, a light emitting unit that emits light in a direction inclined with respect to the optical axis AX0 when viewed from the direction perpendicular to the YZ plane. By combining 76 and the collimating optical system 77, the pitch of the plurality of light beams can be made larger than the arrangement pitch of the light emitting elements 212. The same applies to the second light source unit 74. Therefore, even when the pitch between the light emitting elements 212 of the light source units 73 and 74 is small, it is possible to reduce the loss of light when the combined beam 75 is generated by the light combining unit 75. Thereby, the light source device 72 including the small light source units 73 and 74 and having a small light loss can be realized.

  In each of the light source units 73 and 74, as the distance between the surface FA including the optical axis AX0 and the light emitting element 212 is larger, the inclination angle of the principal ray BL when emitted from the light emitting unit 76 is larger. The mounting tolerance in the light emitting element 212 far from the surface is larger than the mounting tolerance in the light emitting element 212 near the surface FA. Therefore, the influence of the relative relationship between the optical axis of the light emitting element 212 and the optical axis of the collimating optical system 77 as the entire light emitting unit 76 is smaller. Further, the intervals between the principal rays BL emitted from the collimating optical system 77 can be made equal to each other.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in the fourth embodiment, the emission direction of the light emitting element is tilted in the YZ plane and the principal ray of light is incident on a position shifted from the central axis of the second cylindrical lens. A first cylindrical lens in which the flat incident surface and the generatrix of the lens surface when viewed from the surface normal direction of the YZ plane are not parallel may be used. In the above embodiment, an example in which the emission direction of the light emitting element is tilted in either the XZ plane or the YZ plane has been described. However, the emission direction of the light emitting element may be tilted in both the XZ plane and the YZ plane. Moreover, in the said embodiment, although the plano-convex lens was used as a lens which comprises a collimating optical system, you may use a biconvex lens.

  In the above-described embodiment, | θa | = | θd | and | θb | = | θc |, but are not limited thereto. For example, | θa | may not be equal to | θd |. With the plane FA including the optical axis AX0 as a symmetry plane, the greater the distance between the symmetry plane and the light emitting element 212, the greater the inclination angle of the principal ray BL.

  The light source device of each of the above embodiments includes a light emitting unit in which a plurality of light emitting elements are two-dimensionally arranged. However, the light source device may include a light emitting unit in which a plurality of light emitting elements are arranged one-dimensionally. .

  In each of the above-described embodiments, the case where an error occurs in the mounting position of the light emitting element has been described. However, the present invention is also effective when an error occurs in the mounting position of the collimating optical system.

In addition, the shape, number, arrangement, material, and the like of various components of the light source device and the projector are not limited to the above-described embodiment, and can be changed as appropriate.
Moreover, although the example which mounted the illuminating device by this invention in the projector was shown in the said embodiment, it is not restricted to this. The light source device according to the present invention can also be applied to lighting fixtures, automobile headlights, and the like.

  DESCRIPTION OF SYMBOLS 1 ... Projector, 2 ... Light source device, 4R, 4G, 4B ... Light modulation device, 12, 62, 72 ... Light source device, 21, 23, 76 ... Light emission part, 35AA ... 1st collimating optical system, 35BB ... 2nd Collimating optical system, 60 ... projection optical system, 212A ... first light emitting element, 212B ... second light emitting element, 212C ... third light emitting element, 216cA ... first reflecting surface, 216cB ... second reflecting surface .

Claims (9)

A light emitting unit comprising a first light emitting element and a second light emitting element arranged in a first direction;
A first collimating optical system on which the first light emitted from the first light emitting element is incident;
A second collimating optical system on which the second light emitted from the second light emitting element is incident,
The light emitting unit emits the first light from the light emitting unit in a third direction inclined from a second direction perpendicular to the first direction, and the second light is inclined fourth from the second direction. It is configured to be emitted from the light emitting unit in the direction,
In the first collimating optical system, an angle formed between the principal ray of the first light emitted from the first collimating optical system and the second direction is not incident on the first collimating optical system. Arranged so as to be smaller than an angle formed between the principal ray of the first light and the second direction;
The second collimating optical system is configured so that an angle formed between the principal ray of the second light emitted from the second collimating optical system and the second direction is not incident on the second collimating optical system. A light source device disposed so as to be smaller than an angle formed between a principal ray of the second light and the second direction. The first collimating optical system has at least one first lens surface;
The second collimating optical system has at least one second lens surface;
The incident angle of the principal ray of the first light with respect to the first lens surface is larger than 0 ° and smaller than 90 °,
2. The light source device according to claim 1, wherein an incident angle of a principal ray of the second light with respect to the second lens surface is greater than 0 ° and smaller than 90 °.   The second direction is located between the third direction and the fourth direction when viewed from a direction perpendicular to the second direction and the third direction. The light source device described. The light emitting unit further includes a third light emitting element, and is configured to emit the third light emitted from the third light emitting element in a fifth direction inclined from the second direction,
When viewed from a direction perpendicular to the second direction and the third direction, the second light emitting element is located between the first light emitting element and the third light emitting element, and the fourth direction. Is located between the second direction and the fifth direction,
The angle formed between the principal ray of the third light and the second direction when emitted from the light emitting unit is the principal ray of the second light and the second direction when emitted from the light emitting unit. The light source device according to claim 2, wherein the light source device is larger than an angle between the light source device and the light source device.   The light source device according to claim 1, wherein the third direction is parallel to the fourth direction. The light emitting unit further includes a first reflecting surface and a second reflecting surface,
The first light is emitted from the first light emitting element substantially parallel to the first direction,
The first light emitted from the first light emitting element is reflected in the third direction by the first reflecting surface;
The second light is emitted from the second light emitting element substantially parallel to the first direction,
6. The light source according to claim 1, wherein the second light emitted from the second light emitting element is reflected in the fourth direction by the second reflecting surface. 7. apparatus.   The illuminating device provided with the light source device as described in any one of Claim 1- Claim 6.   The lighting device according to claim 7, further comprising a phosphor layer on which at least a part of the first light and the second light is incident. A lighting device comprising the light source device according to claim 7 or 8,
A light modulation device that modulates illumination light emitted from the illumination device according to image information;
And a projection optical system that projects the light modulated by the light modulation device.

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