Light source device, projector and machining device

Abstract

To provide a light source device, a projector, and a machining device that are capable of reducing chromatic aberration.SOLUTION: A light source device 1 comprises first, second, and third optical units 10(R), 10(G), and 10(B) each that emit a laser beam having a different wavelength from each other. The optical unit includes: a plurality of LD packages 21 each emitting a laser beam; a collimator 3 disposed in an optical path of the laser beams; a condensing lens 5 that is disposed on a downstream side in an optical axis direction of the LD packages relative to the collimator 3 and condenses each of the laser beams; a light guiding body 6 that is disposed on the downstream side in the optical axis direction relative to the condensing lens 5 and guides each of the laser beams condensed by the condensing lens 5; and a reduction optical system 4 that is disposed between the collimator 3 and the condensing lens 5 and reduces a beam diameter of the laser beams passing through the collimator 3 in a FAST axis direction α1.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] A beam-combining optical system is known that inputs each laser beam emitted from a plurality of semiconductor laser light sources into an optical fiber and combines them into one (see, for example, Patent Document 1). The beam-combining optical system described in Patent Document 1 is composed of a plurality of semiconductor laser light sources arranged in a matrix, a plurality of collimator lenses that convert the laser beams emitted from each semiconductor laser light source into parallel beams, a first focusing lens (cylindrical lens) that focuses the laser beams that have passed through the collimator lens only in one of a plane including the SLOW axis direction and a plane including the FAST axis direction, a second focusing lens (anamorphic lens) that focuses the laser beams that have passed through the first focusing lens in both of the two planes together with the first focusing lens, and an optical fiber into which each laser beam that has passed through the second focusing lens is input. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-163947 A Summary of the Invention [Problem to be solved by the invention]

[0004] For example, when attempting to project a color image onto a screen using the multiplexing optical system described in Patent Document 1, three multiplexing optical systems are required that respectively irradiate red, green, and blue laser beams with different wavelengths. However, in each multiplexing optical system, the focusing position of the laser beam with respect to the optical fiber may shift depending on the color of the laser beam, i.e., chromatic aberration may occur. As a result, the color image on the screen may be partially blurred.

[0005] An object of the present invention is to provide a light source device, a projector, and a machining device that can reduce chromatic aberration. [Means for solving the problem]

[0006] An aspect of the present invention is a light source device having a first light emitting section and a second light emitting section that emit laser beams having different wavelengths, The first light emitting portion and the second light emitting portion each have A plurality of light emitting elements that emit laser light; a collimator disposed in an optical path of the laser light; a condenser lens disposed downstream of the light emitting element in the optical axis direction with respect to the collimator, the condenser lens condensing each laser beam; a light guide disposed downstream of the light emitting element in the optical axis direction with respect to the condensing lens, the light guide guiding each laser light condensed by the condensing lens; The light source device has a reduction optical system that is disposed between the collimator and the condenser lens and reduces the beam diameter of the laser light passing through the collimator in the fast axis direction of the light emitting element.

[0007] An aspect of the present invention relates to a projector including the above light source device. An aspect of the present invention relates to a machining apparatus including the above-mentioned light source device. Effect of the Invention

[0008] According to the present invention, the chromatic aberration occurring between laser beams having different wavelengths can be cancelled (reduced) by the reduction optical system, and the focusing position of the laser beam with respect to the light guide can be positioned on the incident surface of the light guide, regardless of the wavelength. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic configuration diagram showing a first embodiment of a light source device of the present invention. [Diagram 2]2 is a schematic configuration diagram of one optical unit included in the light source device shown in FIG. [Diagram 3] 3 is a vertical sectional view of a light source included in the optical unit shown in FIG. 2. [Figure 4] 4 is a view of the light source in FIG. 3 as viewed from the direction of arrow A. [Diagram 5] FIG. 4 is a schematic configuration diagram showing a second embodiment of a light source device of the present invention. [Figure 6] FIG. 11 is a schematic configuration diagram showing a third embodiment of a light source device of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a light source device, a projector, and a machining device of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings. First Embodiment A first embodiment of the light source device, projector, and machining device of the present invention will be described with reference to Figs. 1 to 4. The configuration diagram of Fig. 1 shows the arrangement of each part of the light source device in a plan view parallel to the FAST axis direction α1 of the laser light. The upper configuration diagram of Fig. 2 shows the arrangement of each part of the light source device in a plan view parallel to the FAST axis direction α1 of the laser light, and the lower configuration diagram of Fig. 2 shows the arrangement of each part of the light source device in a plan view parallel to the SLOW axis direction α2 of the laser light. In addition, for convenience of explanation, the left side in Fig. 1 will be referred to as "upstream side (or left side) of the light emitting element in the optical axis direction" and the right side will be referred to as "downstream side (or right side) of the light emitting element in the optical axis direction". In addition, the upstream side of the light emitting element in the optical axis direction may be simply referred to as "upstream side", and the downstream side of the light emitting element in the optical axis direction may be simply referred to as "downstream side".

[0011] The light source device 1 shown in Fig. 1 can be applied to a projector 100 that projects an image or the like onto a screen (not shown). The projector 100 includes the light source device 1. In this case, the light source device 1 is configured to irradiate red laser light LB(R), green laser light LB(G), and blue laser light LB(B) that have different wavelengths. Then, a color image can be projected by combining the laser light LB(R), laser light LB(G), and laser light LB(B).

[0012] Specifically, the light source device 1 has a first optical unit 10(R) as a first light-emitting section that emits laser light LB(R), a second optical unit 10(G) as a second light-emitting section that emits laser light LB(G), and a third optical unit 10(B) as a third light-emitting section that emits laser light LB(B).

[0013] The first optical unit 10(R), the second optical unit 10(G) and the third optical unit 10(B) have the same configuration except that they emit different colors of laser light and have different configurations of the reduction optical system 4, which will be described later, so the first optical unit 10(R) will be described as a representative example. Here, "the same configuration" refers to the same positional relationships of the optical components, etc.

[0014] 2, the first optical unit 10(R) includes, arranged in this order from the upstream side to the downstream side in the optical axis direction, a light source 2, a collimator (collimator lens) 3, a reduction optical system 4, a condenser lens 5, and a light guide 6. The configuration of each optical component will be described below.

[0015] The light source 2 has a plurality of LD packages 21. Since each LD package 21 has the same configuration, the configuration of one LD package 21 will be representatively described. As shown in FIG. 3, the LD package 21 includes a laser diode element (LD element) 22, a photodiode 23, and a package 24.

[0016] The laser diode element 22 is a light-emitting element that emits red laser light (semiconductor laser) LB(R). The laser diode element 22 is composed of, for example, a laminate having an active layer (light-emitting layer) and an n-type cladding layer and a p-type cladding layer disposed via the active layer. Both end faces of the active layer are reflective surfaces. When a voltage is applied to the laser diode element 22 in the forward direction, electrons flow from the n-type cladding layer into the active layer, and holes flow from the p-type cladding layer into the active layer, and recombine in the active layer to emit light. Since the refractive index of each cladding layer is lower than that of the active layer, light travels back and forth between the both end faces in the active layer while being amplified. Then, stimulated emission occurs, and the light is irradiated as laser light LB(R).

[0017] The laser light LB(R) emitted by the laser diode element 22 (active layer) is not a completely straight light, but spreads due to diffraction as it travels. The laser diode element 22, which is a laminate, is formed so that the width direction is larger than the thickness direction. As a result, as shown in Fig. 4, the laser light LB(R) spreads in an elliptical shape, and the intensity distribution (far-field pattern) of the laser light LB(R) is such that the beam diameter in the FAST axis direction α1 of the laser light LB(R) is larger than the beam diameter in the SLOW axis direction α2.

[0018] The package 24 collectively houses the laser diode element 22 and the photodiode 23. The package 24 is a so-called CAN-type package, and has a base 241, a cap 242, and a cover glass 243. The base 241 has a disk shape, and includes a disk-shaped portion 244 on which the photodiode 23 is supported, and a support portion 245 formed to protrude from the disk-shaped portion 244 and on which the laser diode element 22 is supported. The disk-shaped portion 244 serves as a flange portion of the package 24 whose outer diameter is expanded to the maximum. When the LD package 21 is fixed to a predetermined position in the light source device 1, the LD package 21 can be stably fixed by the disk-shaped portion 244.

[0019] A cap 242 is fixed to the base 241. The cap 242 is a member that covers the laser diode element 22 and the photodiode 23 supported by the base 241. Furthermore, the cap 242 is formed with a through hole 246 through which the laser light LB(R) passes. The constituent material of the base 241 and the cap 242 is not particularly limited, and may be, for example, a metal material such as aluminum. The cover glass 243 is a glass plate that covers the through-hole 246 from the inside of the cap 242. The laser light LB(R) can pass through the cover glass 243. Note that the package 24 may omit the cover glass 243.

[0020] The LD packages 21 configured as above are arranged in a matrix with multiple rows along the FAST axis direction α1 and multiple columns along the SLOW axis direction α2 of the laser light LB(R). As shown in Fig. 2, in this embodiment, the number of LD packages 21 arranged in the FAST axis direction α1 is three, and the number of LD packages 21 arranged in the SLOW axis direction α2 is also three, but the number arranged in each direction is not limited to this. In addition, the number of LD packages 21 arranged in the FAST axis direction α1 and the number of LD packages 21 arranged in the SLOW axis direction α2 are not limited to be the same, and may be different.

[0021] A collimator 3 is disposed in the optical path of the laser light LB(R), that is, on the optical axis of the laser diode element 22, at a distance from the light source 2. The collimator 3 is composed of a plurality of circular lenses (plano-convex lenses) 31. Each lens 31 has an incident surface 311 on which the laser light LB(R) is incident, and an exit surface 312 from which the laser light LB(R) is exited. The incident surface 311 is configured as a flat surface. The exit surface 312 is configured as a curved convex surface. The effective diameter of the lens 31 is preferably larger than the outer diameter of the disk-shaped portion 244.

[0022] Each lens 31 is disposed facing the laser diode element 22. Each lens 31 is disposed at a position where the optical axis of the laser diode element 22 passes through the center of the lens 31. This allows the laser light LB(R) emitted from each laser diode element 22 to be collimated in both the FAST axis direction α1 and the SLOW axis direction α2. The collimator 3 may be composed of a combination lens.

[0023] A condenser lens 5 is disposed on the optical path of the laser light LB(R) downstream of the collimator 3. The collimator 3 and the condenser lens 5 are spaced apart from each other, and a reduction optical system 4 is disposed between the collimator 3 and the condenser lens 5. The condenser lens 5 is a lens that condenses each laser beam LB(R) toward the light guide 6. The condenser lens 5 has an incident surface 51 on which the laser beam LB(R) is incident, and an exit surface 52 from which the laser beam LB(R) exits. The incident surface 51 is configured as a curved convex surface. The exit surface 52 is configured as a flat surface.

[0024] A light guide 6 is disposed on the optical path of the laser light LB(R) downstream of the focusing lens 5. The light guide 6 is long and has an upstream end face that serves as an incident surface 61 and a downstream end face that serves as an exit surface 62. A plurality of laser lights LB(R) focused by the focusing lens 5 are incident collectively on the incident surface 61. The laser lights LB(R) pass through the light guide 6 and are guided to the exit surface 62, from which they can be emitted. The light guide 6 is not particularly limited, and for example, an optical fiber, an optical waveguide, or the like can be used. In the first optical unit 10(R), the second optical unit 10(G) and the third optical unit 10(B), the distance between the light source 2 and the incident surface 61 of the light guide 6 is equal.

[0025] As described above, when a color image is to be projected on a screen using the multiplexing optical system described in Patent Document 1, for example, the projection device is equipped with three multiplexing optical systems that irradiate red, green, and blue laser beams with different wavelengths. In this case, between each multiplexing optical system, a phenomenon occurs in which the focusing position on the optical fiber shifts in the optical axis direction depending on the color of the laser beam, that is, chromatic aberration occurs. As a result, the output of each optical fiber varies, and the color image on the screen may become, for example, partially blurred.

[0026] Therefore, the light source device 1 is configured to eliminate such problems. The configuration and operation of this device will be described below. 1, in the light source device 1, the first optical unit 10(R), the second optical unit 10(G), and the third optical unit 10(B) each include a reduction optical system 4. Hereinafter, the reduction optical system 4 included in the first optical unit 10(R) will be referred to as the "reduction optical system 4(R)," the reduction optical system 4 included in the second optical unit 10(G) will be referred to as the "reduction optical system 4(G)," and the reduction optical system 4 included in the third optical unit 10(B) will be referred to as the "reduction optical system 4(B)."

[0027] In the first optical unit 10(R), the reduction optical system 4(R) is disposed between the collimator 3 and the condenser lens 5. In the second optical unit 10(G), the reduction optical system 4(G) is disposed between the collimator 3 and the condenser lens 5, and similarly, in the third optical unit 10(B), the reduction optical system 4(B) is disposed between the collimator 3 and the condenser lens 5.

[0028] The reduction optical system 4(R), the reduction optical system 4(G) and the reduction optical system 4(B) have the same configuration except that the reduction optical system 4(G) and the reduction optical system 4(B) each have a moving support mechanism 7, so the reduction optical system 4(R) will be described as a representative example.

[0029] As described above, the intensity distribution of the laser light LB(R) is larger in the FAST axis direction α1 than in the SLOW axis direction α2 (see FIG. 4). That is, the beam diameter (beam width) of the laser light LB(R) is larger in the FAST axis direction α1 than in the SLOW axis direction α2. The reduction optical system 4(R) is configured to reduce the larger beam diameter, i.e., the beam diameter in the FAST axis direction α1.

[0030] As shown in FIG. 2, before and after the reduction optical system 4(R), the beam diameter of the laser light LB(R) transmitted through the collimator 3 is reduced to α1 in the FAST axis direction, but is kept constant in α2 in the SLOW axis direction. Note that the beam diameter in each direction is 1 / e 2 The measurement can be taken between two points where

[0031] That is, in the FAST axis direction α1, the beam diameter Wα1-1 of the laser light LB(R) before passing through the reduction optical system 4(R) becomes a beam diameter Wα1-2 after the laser light LB(R) passes through the reduction optical system 4(R), and the beam diameter Wα1-2 is smaller than the beam diameter Wα1-1. On the other hand, in the SLOW axis direction α2, the beam diameter Wα2-1 of the laser light LB(R) before passing through the reduction optical system 4(R) is equal to the beam diameter Wα2-2 of the laser light LB(R) after passing through the reduction optical system 4(R).

[0032] The reduction optical system 4(R) includes a first cylindrical lens 41, a second cylindrical lens 42, a third cylindrical lens 43, and a fourth cylindrical lens 44, each having a power in the FAST axis direction α1. The first cylindrical lens 41, the second cylindrical lens 42, the third cylindrical lens 43, and the fourth cylindrical lens 44 are arranged in order from the upstream side to the downstream side.

[0033] The first cylindrical lens 41 has an incident surface 411 on which the laser light LB(R) is incident, and an exit surface 412 from which the laser light LB(R) is exited. The incident surface 411 has a convex surface 413 formed so that the protruding height changes continuously along the FAST axis direction α1. On the other hand, the exit surface 412 is configured as a flat surface. Due to such incident surface 411 and exit surface 412, the first cylindrical lens 41 becomes a cylindrical lens having power in the FAST axis direction α1.

[0034] The second cylindrical lens 42 has an incident surface 421 on which the laser light LB(R) is incident, and an exit surface 422 from which the laser light LB(R) is exited. The incident surface 421 has a convex surface 423 formed so that the protruding height changes continuously along the FAST axis direction α1. On the other hand, the exit surface 422 is configured as a flat surface. Due to such incident surface 421 and exit surface 422, the second cylindrical lens 42 becomes a cylindrical lens having power in the FAST axis direction α1.

[0035] The third cylindrical lens 43 has an incident surface 431 on which the laser light LB(R) is incident, and an exit surface 432 from which the laser light LB(R) is exited. The incident surface 431 has a concave surface 433 formed so that the depth changes continuously along the FAST axis direction α1. On the other hand, the exit surface 432 is configured as a flat surface. Due to such incident surface 431 and exit surface 432, the third cylindrical lens 43 becomes a cylindrical lens having power in the FAST axis direction α1.

[0036] The fourth cylindrical lens 44 has an incident surface 441 on which the laser light LB(R) is incident, and an exit surface 442 from which the laser light LB(R) is exited. The incident surface 441 is configured as a flat surface. On the other hand, the exit surface 442 has a concave surface 443 formed so that the depth changes continuously along the FAST axis direction α1. Due to such incident surface 441 and exit surface 442, the fourth cylindrical lens 44 becomes a cylindrical lens having power in the FAST axis direction α1.

[0037] The first cylindrical lens 41 located at the most upstream side and the fourth cylindrical lens 44 located at the most downstream side constitute one set of reduction optical systems 4(R). The second cylindrical lens 42 and the third cylindrical lens 43 located between the first cylindrical lens 41 and the fourth cylindrical lens 44 constitute one set of reduction optical systems 4(R). In this way, the reduction optical system 4(R) is composed of two sets of reduction optical systems 4(R). As a result, the beam diameter in the FAST axis direction α1 is reduced as the laser light LB(R) advances.

[0038] As described above, the reduction optical system 4(G) and the reduction optical system 4(B) each have a movement support mechanism 7. As shown in Fig. 1, each movement support mechanism 7 supports the second cylindrical lens 42 to the fourth cylindrical lens 44 among the first cylindrical lens 41 to the fourth cylindrical lens 44 so that they can move along the optical axis direction. This allows the positions of the second cylindrical lens 42 to the fourth cylindrical lens 44 to be adjusted (finely adjusted).

[0039] Each of the movement support mechanisms 7 has three actuators 71 that are actuated by energization. Of the three actuators 71, one actuator 71 is responsible for moving the second cylindrical lens 42, the other actuator 71 is responsible for moving the third cylindrical lens 43, and the remaining actuator 71 is responsible for moving the fourth cylindrical lens 44. This makes it possible to adjust the positions of the second cylindrical lens 42 to the fourth cylindrical lens 44 independently of one another.

[0040] The configuration of the actuator 71 is not particularly limited, and may be, for example, a configuration including a motor 72, a ball screw 73, and a linear guide 74, with the motor 72 and the linear guide 74 connected via the ball screw 73. This allows the positions of the second cylindrical lens 42 to the fourth cylindrical lens 44 to be adjusted with high precision.

[0041] The focusing position of the laser beam LB(R) with respect to the light guide 6 can be positioned on the incident surface 61 of the light guide 6 by the reduction optical system 4(R).

[0042] Furthermore, if the distance between the first cylindrical lens 41 to the fourth cylindrical lens 44 in the reduction optical system 4(G) is the same as the distance between the first cylindrical lens 41 to the fourth cylindrical lens 44 in the reduction optical system 4(R), due to the chromatic aberration described above, the focusing position of the laser light LB(G) with respect to the light guide 6 will be located either upstream or downstream of the incident surface 61 of the light guide 6.

[0043] Similarly, even if the distance between the first cylindrical lens 41 to the fourth cylindrical lens 44 in the reduction optical system 4(B) is the same as the distance between the first cylindrical lens 41 to the fourth cylindrical lens 44 in the reduction optical system 4(R), due to the chromatic aberration described above, the focusing position of the laser light LB(B) with respect to the light guide 6 will be located either upstream or downstream of the incident surface 61 of the light guide 6.

[0044] Therefore, in the reduction optical system 4(G), the positions of the second cylindrical lens 42 to the fourth cylindrical lens 44 are adjusted so as to cancel (reduce) the chromatic aberration. As a result, the focusing position of the laser light LB(G) with respect to the light guiding body 6 can be positioned on the incident surface 61 of the light guiding body 6, similar to the focusing position of the laser light LB(R) with respect to the light guiding body 6.

[0045] Also, in the reduction optical system 4(B), the positions of the second cylindrical lens 42 to the fourth cylindrical lens 44 are adjusted so as to cancel (reduce) chromatic aberration. This allows the focusing position of the laser light LB(B) on the light guiding body 6 to be positioned on the incident surface 61 of the light guiding body 6, similar to the focusing position of the laser light LB(R) on the light guiding body 6.

[0046] With the above-mentioned configuration, the output of each light guide 6 becomes equal, and the color image on the screen becomes a clear image. In addition, each reduction optical system 4 can reduce spherical aberration. And, due to the synergistic effect of the reduction in spherical aberration and the reduction in chromatic aberration, it is possible to further prevent the decrease in the coupling efficiency for each light guide 6.

[0047] <Second embodiment> Hereinafter, a second embodiment of the light source device, projector, and machining device of the present invention will be described with reference to FIG. 5. The differences from the previously described embodiment will be mainly described, and descriptions of similar points will be omitted. This embodiment is similar to the first embodiment except that the configuration of the reduction optical system is different.

[0048] 5, in this embodiment, the reduction optical system 4 includes a first cylindrical lens 45 having power in the FAST axis direction α1, a second cylindrical lens 46, and a third cylindrical lens 47. The first cylindrical lens 45, the second cylindrical lens 46, and the third cylindrical lens 47 are arranged in order from the upstream side to the downstream side.

[0049] The first cylindrical lens 45 has an incident surface 451 on which the laser light LB(R) is incident, and an exit surface 452 from which the laser light LB(R) is exited. The incident surface 451 has a convex surface 453 formed so that the protruding height changes continuously along the FAST axis direction α1. The exit surface 452 has a concave surface 454 formed so that the depth changes continuously along the FAST axis direction α1. Due to such incident surface 451 and exit surface 452, the first cylindrical lens 45 becomes a cylindrical lens having power in the FAST axis direction α1.

[0050] The second cylindrical lens 46 has an incident surface 461 on which the laser light LB(R) is incident, and an exit surface 462 from which the laser light LB(R) is exited. The incident surface 461 has a concave surface 463 formed so that the depth changes continuously along the FAST axis direction α1. On the other hand, the exit surface 462 also has a concave surface 464 formed so that the depth changes continuously along the FAST axis direction α1. With such incident surface 461 and exit surface 462, the second cylindrical lens 46 becomes a cylindrical lens having power in the FAST axis direction α1.

[0051] The third cylindrical lens 47 has an incident surface 471 on which the laser light LB(R) is incident, and an exit surface 472 from which the laser light LB(R) is exited. The incident surface 471 is configured as a flat surface. On the other hand, the exit surface 472 has a concave surface 473 formed so that the depth changes continuously along the FAST axis direction α1. Due to such incident surface 471 and exit surface 472, the third cylindrical lens 47 becomes a cylindrical lens having power in the FAST axis direction α1.

[0052] The first cylindrical lens 45 and the second cylindrical lens 46 constitute one set of reduction optical systems 4. The first cylindrical lens 45 and the third cylindrical lens 47 constitute one set of reduction optical systems 4. In this way, the reduction optical system 4 is made up of two sets of reduction optical systems 4. This makes it possible to reduce the beam diameter in the FAST axis direction α1 toward the downstream side.

[0053] As in the first embodiment, at least one of the first cylindrical lens 45, the second cylindrical lens 46, and the third cylindrical lens 47 is supported so as to be movable. In this case, for example, the second cylindrical lens 46 and the third cylindrical lens 47 may be made movable.

[0054] <Third embodiment> Hereinafter, a third embodiment of the light source device, projector, and machining device of the present invention will be described with reference to FIG. 6. The differences from the previously described embodiments will be mainly described, and descriptions of similar points will be omitted. This embodiment is similar to the first embodiment, except that the application mode of the light source device is different.

[0055] 6, the light source device 1 can be applied to a machining apparatus 200 that performs laser processing. The machining apparatus 200 includes the light source device 1. In this case, the light source device 1 includes two third optical units 10(B) that respectively irradiate blue laser light LB (B1) and laser light LB (B2) having different wavelengths from each other, for example.

[0056] Of the two third optical units 10(B), one third optical unit 10(B) emits a laser beam LB(B1). The other third optical unit 10(B) emits a laser beam LB(B2) having a wavelength different from that of the laser beam LB(B1). By multiplexing the laser beam LB(B1) and the laser beam LB(B1), for example, laser processing can be performed by the multiplexed beam.

[0057] Although the light source device, projector, and machining device of the present invention have been described above with reference to the illustrated embodiments, the present invention is not limited to these, and each component of the light source device, projector, and machining device can be replaced with any component that can achieve the same function. Also, any component can be added.

[0058] Furthermore, the light source device, projector, and machining device of the present invention may be a combination of any two or more configurations (features) of the above-described embodiments. In addition, the reduction optical system 4 has four cylindrical lenses in the first embodiment and three cylindrical lenses in the second embodiment, but the number of cylindrical lenses arranged is not particularly limited and can be two or five or more.

[0059] Furthermore, the reduction optical system 4(G) and the reduction optical system 4(B) each have a movement support mechanism 7, but the reduction optical system 4(R) may also have a movement support mechanism 7. In addition, in the first embodiment, the movable support mechanism 7 is configured to movably support the second cylindrical lens 42 to the fourth cylindrical lens 44 among the first cylindrical lens 41 to the fourth cylindrical lens 44, but is not limited to this and may be configured, for example, to movably support all of the first cylindrical lens 41 to the fourth cylindrical lens 44.

[0060] [Aspects] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0061] (Item 1) A light source device according to one aspect of the present invention comprises: A light source device having a first light emitting section and a second light emitting section that emit laser beams having different wavelengths, The first light emitting portion and the second light emitting portion each have A plurality of light emitting elements that emit laser light; a collimator disposed in an optical path of the laser light; a condenser lens disposed downstream of the light emitting element in the optical axis direction with respect to the collimator, the condenser lens condensing each laser beam; a light guide disposed downstream of the light emitting element in the optical axis direction with respect to the condensing lens, the light guide guiding each laser light condensed by the condensing lens; The laser beam is focused onto the light emitting element by a reduction optical system disposed between the collimator and the condenser lens, the reduction optical system reducing a beam diameter of the laser beam passing through the collimator in a fast axis direction of the light emitting element.

[0062] According to the light source device described in paragraph 1, chromatic aberration occurring between laser beams having different wavelengths can be offset (reduced) by the reduction optical system.

[0063] (2) In the light source device according to the first aspect, The reduction optical system has a plurality of cylindrical lenses having power in the direction of the fast axis of the light emitting element.

[0064] According to the light source device described in paragraph 2, the beam diameter of the laser light can be reduced in the FAST axis direction with a simple configuration using a cylindrical lens.

[0065] (Item 3) In the light source device according to item 2, The reduction optical system of at least one of the first light emitting section and the second light emitting section has a moving support mechanism that supports at least one cylindrical lens of the plurality of cylindrical lenses so that the cylindrical lens is movable along the optical axis direction.

[0066] According to the light source device described in the third aspect, the position of the cylindrical lens can be adjusted (finely adjusted).

[0067] (4) In the light source device according to the third aspect, The movement support mechanism has an actuator that is activated by energization.

[0068] According to the light source device described in the fourth aspect, the position of the cylindrical lens can be adjusted (finely adjusted) with high precision.

[0069] (Item 5) In the light source device according to any one of items 1 to 4, The reduction optical system is made up of a plurality of sets of reduction optical systems.

[0070] According to the light source device described in paragraph 5, the beam diameter in the FAST axis direction is reduced just enough as the laser light advances.

[0071] (Item 6) In the light source device according to item 5, Each of the reduction optical systems has, in order from the upstream side in the optical axis direction, a first cylindrical lens, a second cylindrical lens, a third cylindrical lens, and a fourth cylindrical lens, with the first cylindrical lens and the fourth cylindrical lens forming one set of reduction optical systems, and the second cylindrical lens and the third cylindrical lens forming another set of reduction optical systems.

[0072] According to the light source device described in paragraph 6, the beam diameter in the FAST axis direction is reduced just enough as the laser light advances.

[0073] (Item 7) In the light source device according to item 6, the first cylindrical lens has a convex entrance surface and a flat exit surface; the second cylindrical lens has a convex entrance surface and a flat exit surface, the third cylindrical lens has an entrance surface having a concave surface and an exit surface formed of a flat surface; The fourth cylindrical lens has an entrance surface formed of a flat surface and an exit surface having a concave surface.

[0074] According to the light source device described in paragraph 7, each cylindrical lens has just the right amount of power in the FAST axis direction.

[0075] (Item 8) In the light source device according to item 5, The reduction optical system has, in order from the upstream side in the optical axis direction, a first cylindrical lens, a second cylindrical lens, and a third cylindrical lens, and the first cylindrical lens and the second cylindrical lens form one set of reduction optical systems, and the first cylindrical lens and the third cylindrical lens form another set of reduction optical systems.

[0076] According to the light source device described in paragraph 8, the beam diameter in the FAST axis direction is reduced just enough as the laser light advances.

[0077] (Item 9) In the light source device according to item 8, the first cylindrical lens has an entrance surface having a convex surface and an exit surface having a concave surface; the second cylindrical lens has a concave entrance surface and a concave exit surface, The third cylindrical lens has an entrance surface formed of a flat surface and an exit surface having a concave surface.

[0078] According to the light source device described in paragraph 9, each cylindrical lens has just the right amount of power in the FAST axis direction.

[0079] (Item 10) A projector according to one aspect comprises: The light source device according to any one of items 1 to 9 is provided.

[0080] According to the projector described in paragraph 10, chromatic aberration occurring between laser beams having different wavelengths can be offset (reduced) by the reduction optical system of the light source device.

[0081] (Item 11) A machining apparatus according to one aspect comprises: The light source device according to any one of items 1 to 9 is provided.

[0082] According to the machining device described in item 11, chromatic aberration occurring between laser beams having different wavelengths can be offset (reduced) by the reduction optical system of the light source device. [Explanation of symbols]

[0083] 1 Light source device 10(R) First optical unit 10(G) Second optical unit 10(B) Third optical unit 2 light source 21 LD Package 22 Laser diode element (LD element) 23 Photodiode 24 Packages 241 Base 242 Cap 243 Coverslip 244 Disc-shaped part 245 Support part 246 Through hole 3 Collimator (collimator lens) 31 Lens (plano-convex lens) 311 Incidence plane 312 Exit surface 4 Reduction optical system 4(R) Reduction optical system 4(G) Reduction optical system 4(B) Reduction optical system 41 First cylindrical lens 411 Entrance plane 412 Exit surface 413 Convex 42 2nd cylindrical lens 421 Entrance plane 422 Exit surface 423 Convex 43 3rd cylindrical lens 431 Entrance plane 432 Exit surface 433 Concave 44 4th cylindrical lens 441 Entrance plane 442 Exit surface 443 Concave 45 1st cylindrical lens 451 Entrance plane 452 Exit surface 453 Convex 454 Concave 46 2nd cylindrical lens 461 Entrance plane 462 Exit surface 463 Concave 464 Concave 47 3rd cylindrical lens 471 Entrance plane 472 Exit surface 473 Concave 5 Condenser lens 51 Incidence plane 52 Exit surface 6 Light guide 61 Entrance plane 62 Exit surface 7 Moving support mechanism 71 Actuator 72 Motor 73 Ball screw 74 Linear Guide 100 Projectors 200 Machining equipment LB(R) Laser light LB(G) Laser light LB(B) Laser light LB(B1) Laser light LB(B2) Laser light Wα1-1 Beam diameter Wα1-2 Beam diameter Wα2-1 Beam diameter Wα2-2 Beam diameter α1 FAST axial direction α2 SLOW axis direction

Claims

1. A light source device having a first light emitting section and a second light emitting section that emit laser beams having different wavelengths, Each of the first light emitting unit and the second light emitting unit includes a plurality of light emitting elements that emit laser light; a collimator disposed in an optical path of the laser light; a condenser lens disposed downstream of the light emitting element in the optical axis direction with respect to the collimator, the condenser lens condensing each laser beam; a light guide disposed downstream of the light emitting element in the optical axis direction with respect to the condensing lens, the light guide guiding each laser light condensed by the condensing lens; a reduction optical system that is disposed between the collimator and the condenser lens and that is composed of a plurality of cylindrical lenses that reduce a beam diameter of the laser light passing through the collimator in a FAST axis direction of the light-emitting element, and the reduction optical system of at least one of the first light-emitting unit and the second light-emitting unit has a moving support mechanism that supports at least one of the plurality of cylindrical lenses so as to be movable along an optical axis direction; A light source device characterized in that, using the movable support mechanism, the cylindrical lens is positioned so as to cancel out chromatic aberration between the concentrated laser beams emitted from the first light-emitting portion and the second light-emitting portion.

2. 2. The light source device according to claim 1, wherein the movement support mechanism includes an actuator that is activated by energization.

3. 3. The light source device according to claim 1, wherein the reduction optical system is composed of a plurality of reduction optical systems.

4. The light source device of claim 3, wherein the reduction optical system has, in order from the upstream side in the optical axis direction, a first cylindrical lens, a second cylindrical lens, a third cylindrical lens, and a fourth cylindrical lens, the first cylindrical lens and the fourth cylindrical lens forming one set of reduction optical systems, and the second cylindrical lens and the third cylindrical lens forming another set of reduction optical systems.

5. the first cylindrical lens has an entrance surface having a convex surface and an exit surface configured as a flat surface, the second cylindrical lens has an entrance surface having a convex surface and an exit surface configured as a flat surface, the third cylindrical lens has an entrance surface having a concave surface and an exit surface configured as a flat surface, The light source device according to claim 4 , wherein the fourth cylindrical lens has an entrance surface that is a flat surface and an exit surface that is a concave surface.

6. the reduction optical system has, in order from the upstream side in the optical axis direction, a first cylindrical lens, a second cylindrical lens, and a third cylindrical lens, the first cylindrical lens and the second cylindrical lens constituting one set of reduction optical systems, and the first cylindrical lens and the third cylindrical lens constituting another set of reduction optical systems. The light source device according to claim 3 .

7. the first cylindrical lens has an entrance surface having a convex surface and an exit surface having a concave surface; the second cylindrical lens has a concave entrance surface and a concave exit surface, The light source device according to claim 6 , wherein the third cylindrical lens has an entrance surface formed of a flat surface and an exit surface having a concave surface.

8. A projector comprising the light source device according to any one of claims 1 to 7.

9. A machining apparatus comprising the light source device according to any one of claims 1 to 7.

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