Light emitting device, light source unit, light source device and fiber laser

Abstract

The light-emitting device includes, for example: a light-emitting element having a fast axis and a slow axis and emitting laser light; a housing that accommodates the light-emitting element and is provided with a window through which the laser light emitted from the light-emitting element passes; a first optical element that is arranged outside the housing and converges the laser light passing through the window in the fast axis direction; and a second optical element that collimates the laser light that has passed through the first optical element in the fast axis direction in a state in which the beam width in the fast axis direction is narrower than the beam width in the fast axis direction in the incident surface of the first optical element, and the second optical element is arranged at a position closer to the first optical element than the convergence point of the laser light in the fast axis direction of the first optical element.

Description

Technical Field

[0001] The present invention relates to a light emitting device, a light source unit, a light source device and a fiber laser. Background Art

[0002] In the past, the following light-emitting device is known, which includes a light-emitting element having a fast axis and a slow axis, a lens for collimating in the fast axis direction, and a lens for collimating in the slow axis direction, wherein light emitted from the light-emitting element is collimated in the fast axis direction and then collimated in the slow axis direction (for example, Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: U.S. Patent Application Publication No. 2018 / 0031850 Summary of the Invention

[0006] -Problems to be solved by the invention-

[0007] However, in a structure in which a light-emitting element is housed in an airtightly sealed housing and a lens for collimating the light in the fast-axis direction is arranged outside the housing, the light from the light-emitting element is collimated while expanding at a relatively large angle in the fast-axis direction, resulting in a problem such as an increase in the beam width in the fast-axis direction.

[0008] Therefore, one of the objects of the present invention is to obtain a light-emitting device, a light source unit, a light source device, and a fiber laser that can further reduce the beam diameter in a structure in which, for example, a light-emitting element is housed in a housing and a lens for collimating light emitted from the light-emitting element is arranged outside the housing.

[0009] -Methods for solving the problem-

[0010] The light-emitting device of the present invention, for example, includes: a light-emitting element having a fast axis and a slow axis and emitting laser light; a housing that accommodates the light-emitting element and is provided with a window through which the laser light emitted from the light-emitting element passes; a first optical element that is arranged outside the housing and converges the laser light passing through the window in the fast axis direction; and a second optical element that collimates the laser light that has passed through the first optical element in the fast axis direction in a state in which the beam width in the fast axis direction is narrower than the beam width in the fast axis direction in the incident surface of the first optical element, and the second optical element is arranged at a position closer to the first optical element than the convergence point of the laser light in the fast axis direction of the first optical element.

[0011] Alternatively, in the light-emitting device, the first optical element may be a convex lens at least in the fast axis direction, and the second optical element may be a concave lens at least in the fast axis direction.

[0012] In the light emitting device, the first optical element may be a lens having a plane-symmetrical shape with respect to a virtual center plane intersecting the fast axis direction of the laser light.

[0013] In the light emitting device, the first optical element may be a lens having an axisymmetric shape with respect to a central axis along the optical axis of the laser light.

[0014] The light emitting device may include a third optical element that collimates the laser light having passed through the first optical element in a slow axis direction.

[0015] In the light-emitting device, the third optical element may be located between the first optical element and the second optical element.

[0016] The light-emitting device may also include a base having a surface roughly along the optical axis direction of the laser, the first optical element and the second optical element are located on the surface, and at least one of the first optical element and the second optical element is fixed to a protrusion protruding from the surface via a joining portion.

[0017] In the light emitting device, at least one of the first optical element and the second optical element may be fixed to the protruding portion via the joining portions at a plurality of locations.

[0018] In the light emitting device, the joining portion may be interposed between at least one of the first optical element and the second optical element and the protruding portion in a direction along the optical axis.

[0019] In the light emitting device, the joining portion may be interposed between at least one of the first optical element and the second optical element and the protruding portion in a direction intersecting the direction along the optical axis.

[0020] In the light emitting device, the protrusion may be the light emitting element.

[0021] The light emitting device may include a shielding portion that shields leakage of the laser light toward the joining portion.

[0022] In the light emitting device, the shielding portion may include a reflecting portion that reflects the leaked light in a direction opposite to an incident direction of the leaked light.

[0023] In the light emitting device, the shielding portion may include an absorbing portion that absorbs energy of the leaked light.

[0024] In the light-emitting device, the first optical element may be fixed to the light-emitting element.

[0025] In the light emitting device, the housing may be hermetically sealed.

[0026] Furthermore, the light source unit of the present invention includes, for example: the light emitting device; and an optical component that guides light emitted from the light emitting device to an input portion of one optical fiber.

[0027] The light source unit may also include: a first subunit including the light emitting element that emits laser light toward a first direction, and the first optical element and the second optical element that transmit the laser light from the light emitting element toward the first direction; a second subunit including the light emitting element that is arranged away from the first subunit in the first direction and emits laser light in a direction opposite to the first direction, and the first optical element and the second optical element that transmit the laser light from the light emitting element in a direction opposite to the first direction; and a shielding portion that shields at least one of the leakage light of the laser light from the first subunit and the leakage light of the laser light from the second subunit.

[0028] In the light source unit, the shielding portion may be located between the first subunit and the second subunit.

[0029] Furthermore, the light source device of the present invention includes, for example, the light source unit described above.

[0030] Furthermore, the fiber laser of the present invention includes, for example: the light source device described above; and an optical amplification fiber that amplifies laser light emitted from the light source device.

[0031] -Effects of the Invention-

[0032] According to the present invention, in a structure in which a light emitting element is housed in a housing and a lens for collimating light emitted from the light emitting element is provided outside the housing, the beam diameter can be further reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is an illustrative and schematic side view of the light emitting device of the first embodiment.

[0034] Figure 2 It is an illustrative and schematic top view of the light emitting device according to the first embodiment.

[0035] Figure 3 It is an illustrative and schematic side view of a light emitting device according to a second embodiment.

[0036] Figure 4 It is an illustrative and schematic top view of a light emitting device according to a second embodiment.

[0037] Figure 5 It is an illustrative and schematic side view of a light emitting device according to a third embodiment.

[0038] Figure 6 It is an illustrative and schematic top view of a light emitting device according to a third embodiment.

[0039] Figure 7 1 is an illustrative and schematic plan view of a light source unit according to a fourth embodiment.

[0040] Figure 8 yes Figure 7 Sectional view VIII-VIII of FIG.

[0041] Figure 9 This is an illustrative and schematic plan view of a portion of the light source unit according to the fourth embodiment, and shows a mounting structure of the first optical element.

[0042] Figure 10 This is an illustrative and schematic plan view of a portion of the light source unit according to the fourth embodiment, and shows a mounting structure of the second optical element.

[0043] Figure 11 This is an illustrative and schematic plan view of a portion of the light source unit according to the fifth embodiment, and shows a mounting structure of the first optical element.

[0044] Figure 12 This is an illustrative and schematic rear view of a portion of the light source unit according to the fifth embodiment, and shows a mounting structure of the first optical element.

[0045] Figure 13 This is an illustrative and schematic rear view of a portion of the light source unit according to the sixth embodiment, and shows a mounting structure of a first optical element.

[0046] Figure 14 It is an illustrative and schematic top view of a portion of a light source unit according to a seventh embodiment.

[0047] Figure 15 It is an illustrative and schematic side view of a shielding portion included in the light source unit according to the seventh embodiment.

[0048] Figure 16 It is an illustrative and schematic side view (partial cross-sectional view) of a shielding portion included in a light source unit according to an eighth embodiment.

[0049] Figure 17It is an illustrative and schematic top view of a portion of a light source unit according to a ninth embodiment.

[0050] Figure 18 It is an illustrative and schematic side view of a shielding portion included in the light source unit according to the ninth embodiment.

[0051] Figure 19 It is an illustrative and schematic top view of a portion of a light source unit according to a tenth embodiment.

[0052] Figure 20 This is an exemplary structural diagram of a light source device according to the eleventh embodiment.

[0053] Figure 21 This is an exemplary structural diagram of a fiber laser according to a twelfth embodiment. DETAILED DESCRIPTION

[0054] The following discloses exemplary embodiments of the present invention. The structures of the embodiments shown below and the functions and results (effects) thereof are merely examples. The present invention can also be implemented using structures other than those disclosed in the following embodiments. In addition, according to the present invention, at least one of the various effects (including derivative effects) obtained by the structures can be obtained.

[0055] The multiple embodiments shown below possess the same structure.Thus, according to the structure of each embodiment, the same action and effect based on this same structure can be obtained.In addition, the following sometimes give the same symbol to these same structures, and omit repeated description.

[0056] In this specification, ordinal numbers are given for the convenience of distinguishing between components, parts, etc., and do not indicate priority or serial numbers.

[0057] In each drawing, the X direction is indicated by an arrow X, the Y direction is indicated by an arrow Y, and the Z direction is indicated by an arrow Z. The X direction, the Y direction, and the Z direction intersect with each other and are orthogonal to each other.

[0058] In addition, Figures 1 to 6 In FIG. 14 , the optical path of the laser light L is shown by a solid arrow.

[0059] [First embodiment]

[0060] Figure 1 1A is a side view showing a light emitting device 1A according to the first embodiment. Figure 2 It is a plan view showing the light emitting device 1A.

[0061] [Structure of Light Emitting Device]

[0062] like Figure 1 、 2As shown, the light emitting device 1A includes a light emitting module 10 , a first optical element 41A, a second optical element 42A, and a third optical element 43A.

[0063] The light emitting module 10 includes a light emitting unit 30 and a housing 20 that houses the light emitting unit 30 .

[0064] The housing 20 is a rectangular parallelepiped box and houses the light emitting unit 30. The housing 20 includes a wall member 21 and a window member 22. The wall member 21 is made of, for example, a metal material.

[0065] The housing 20 also includes a base 21a. The base 21a has a plate-like shape that intersects the Z direction. The base 21a is, for example, a portion (bottom wall) of the wall member 21. The base 21a is made of a metal material with high thermal conductivity, such as oxygen-free copper. Oxygen-free copper is an example of a copper-based material. Alternatively, the base 21a may be provided separately from the wall member 21.

[0066] An opening 21b is provided at the end of the wall member 21 in the X direction. A window member 22 is attached to the opening 21b, which transmits the laser light L. The window member 22 intersects and is perpendicular to the X direction. Laser light L emitted from the light-emitting unit 30 in the X direction passes through the window member 22 and is emitted out of the light-emitting device 1A. Laser light L is emitted from the light-emitting device 1A in the X direction. The window member 22 is an example of a window.

[0067] The boundaries between the multiple members (not shown) that make up the wall member 21 (housing 20) and the boundary between the wall member 21 and the window member 22 are sealed so that gas cannot pass through. In other words, the housing 20 is hermetically sealed. The window member 22 is also part of the wall member 21.

[0068] The light emitting unit 30 includes a base 31 and a light emitting element 32 .

[0069] The base 31 has a plate-like shape, for example, that intersects and is perpendicular to the Z direction. The base 31 can be made of an insulating material with relatively high thermal conductivity, such as aluminum nitride (AIN), ceramic, or glass. A metallization layer (not shown) is formed on the base 31 to serve as an electrode for supplying power to the light-emitting element 32.

[0070] like Figure 1 、 2 As shown, the base 31 is mounted on the top surface 21c of the base 21a. The light emitting element 32 is mounted on the top surface 31a of the base 31. That is, the light emitting element 32 is mounted on the base 21a via the base 31.

[0071] The light-emitting element 32 is, for example, a semiconductor laser element having a fast axis (FA) and a slow axis (SA). The light-emitting element 32 has an elongated shape extending in the X direction. The light-emitting element 32 emits laser light L in the X direction from an emission opening (not shown) provided at an end in the X direction. The light-emitting unit 30 is mounted such that the fast axis of the light-emitting element 32 is along the Z direction, and the slow axis is along the Y direction. The Z direction is an example of a fast axis, and the Y direction is an example of a slow axis.

[0072] [Structure and arrangement of each optical element]

[0073] Laser light L emitted from the light emitting element 32 is collimated in at least the Z and Y directions by the first optical element 41A, the second optical element 42A, and the third optical element 43A in sequence. The first optical element 41A, the second optical element 42A, and the third optical element 43A are all disposed outside the housing 20 .

[0074] In this embodiment, the first optical element 41A, the second optical element 42A, and the third optical element 43A are arranged in sequence in the X direction and are all lenses. Laser light L emitted from the light emitting element 32 passes through the first optical element 41A, the second optical element 42A, and the third optical element 43A in sequence. Furthermore, from the time the laser light is emitted from the light emitting element 32 until it passes through the first optical element 41A, the second optical element 42A, and the third optical element 43A, the optical axis of the laser light L is linear, with the fast axis of the laser light L oriented along the Z direction and the slow axis of the laser light L oriented along the Y direction.

[0075] The first optical element 41A is slightly separated from the window member 22 in the X direction, or is in contact with the window member 22 in the X direction.

[0076] The laser light L passing through the window member 22 is incident on the first optical element 41A. Figure 1 As shown, the first optical element 41A converges the laser light L at least in the Z direction. The first optical element 41A is a convex lens at least in the Z direction, in other words, is a convex lens at least in a cross section perpendicular to the Y direction.

[0077] In this embodiment, as an example, the first optical element 41A has a plane-symmetrical shape relative to a virtual center plane Vc1, which is a plane intersecting and orthogonal to the Z direction. The incident surface 41a and the exit surface 41b of the first optical element 41A have generatrixes along the Y direction and have cylindrical surfaces extending in the Y direction. The incident surface 41a is a convex surface that bulges in the direction opposite to the X direction. Furthermore, the exit surface 41b is a convex surface that bulges in the X direction. The exit surface 41b protrudes further than the incident surface 41a. The first optical element 41A is a cylindrical lens.

[0078] like Figure 1As shown, the beam width Wz of the laser light L from the first optical element 41A in the Z direction narrows as it travels in the X direction. The laser light L, which has been converged at least in the Z direction by the first optical element 41A, enters the second optical element 42A. The beam width is the width of the region in the laser beam profile where the light intensity exceeds a given value. The given value is, for example, 1 / e of the peak light intensity. 2 .

[0079] The second optical element 42A collimates the laser light L in the Z direction while maintaining a beam width Wz2 in the Z direction smaller than a beam width Wz1 in the Z direction at the incident surface 41a of the first optical element 41A. The second optical element 42A is a concave lens at least in the Z direction, or in other words, a concave lens at least in a cross section perpendicular to the Y direction. The second optical element 42A can also be referred to as a collimating lens.

[0080] In this embodiment, as an example, the second optical element 42A has a plane-symmetrical shape with respect to a virtual center plane Vc2, which is a plane intersecting and orthogonal to the Z direction. The incident surface 42a and the exit surface 42b of the second optical element 42A have a generatrix along the Y direction and a cylindrical surface extending in the Y direction. The incident surface 42a is a convex surface that convexly projects in the direction opposite to the X direction. Furthermore, the exit surface 42b is a concave surface that is concave in the X direction. When viewed from the Y direction, the center portion of the exit surface 42b in the Z direction is located further away from the X direction than the two Z-direction end portions.

[0081] The second optical element 42A is arranged closer to the first optical element 41A than the convergence point Pcz in the Z direction of the laser light L generated by the first optical element 41A.

[0082] like Figure 2 As shown, the Y-direction beam width Wy of the laser light L emitted from the light-emitting element 32 and passing through the first optical element 41A and the second optical element 42A expands as it travels in the X-direction. The laser light L, which has a thicker tip and has expanded in the Y-direction after passing through the second optical element 42A, enters the third optical element 43A. The third optical element 43A collimates the laser light L in the Y-direction. The third optical element 43A is a convex lens at least in the Y-direction, or in other words, a convex lens at least in a cross-section perpendicular to the Y-direction. The second optical element 42A can also be called a collimating lens.

[0083] In this embodiment, as an example, the third optical element 43A has a plane-symmetrical shape with respect to a virtual center plane Vc3, which is a plane intersecting and orthogonal to the Y direction. The incident surface 43a and the exit surface 43b of the third optical element 43A have generatrixes along the Z direction and cylindrical surfaces extending in the Z direction. The incident surface 43a is a plane orthogonal to the X direction. The exit surface 43b is a convex curved surface convex in the X direction.

[0084] As described above, in this embodiment, the first optical element 41A is disposed outside the housing 20 and converges the laser light L in the Z direction (fast axis direction) after passing through the window member 22 (window) provided in the housing 20. Furthermore, the second optical element 42A collimates the laser light L that has passed through the first optical element 41A in the Z direction while maintaining a beam width Wz2 in the Z direction smaller than the beam width Wz1 in the Z direction at the incident surface 41a of the first optical element 41A.

[0085] like Figure 1 As shown in FIG. 1 , the beam width of the laser light L emitted from the light emitting element 32 in the Z direction expands as it advances in the X direction. Therefore, assuming that the first optical element 41A is not provided, a collimating lens (not shown) for collimating in the Z direction is provided instead of the first optical element 41A. In this case, as shown in FIG. Figure 1 As shown by the two-dot chain line in FIG, collimated laser light Lv with a wider beam width Wz1 can be obtained. In contrast, in this embodiment, the laser light L focused in the Z direction by the first optical element 41A is collimated by the second optical element 42A while the beam width Wz2 in the Z direction is narrower than the beam width Wz1 in the Z direction at the incident surface 41a of the first optical element 41A. Therefore, according to this embodiment, the beam width Wzc in the Z direction of the collimated laser light L can be further reduced.

[0086] Furthermore, in the present embodiment, the second optical element 42A is arranged closer to the first optical element 41A than the convergence point Pcz in the Z direction of the laser light L generated by the first optical element 41A.

[0087] If the second optical element 42A is positioned farther from the first optical element 41A than the convergence point Pcz, the convergence point Pcz may appear on the optical path of the laser light L between the first and second optical elements 41A, 42A. In this case, problems such as dust accumulation at the convergence point Pcz, where the energy density is high, may occur. To address this issue, in this embodiment, the second optical element 42A is positioned closer to the first optical element 41A than the convergence point Pcz. Therefore, the second optical element 42A collimates the laser light L before it reaches the convergence point Pcz. In other words, according to this embodiment, the convergence point Pcz is not present on the optical path of the laser light L, thus preventing problems caused by the convergence point Pcz.

[0088] In the present embodiment, the first optical element 41A is a convex lens at least in the Z direction, and the second optical element 42A is a concave lens at least in the Z direction.

[0089] According to the above-described configuration, the first optical element 41A and the second optical element 42A can be realized with a relatively simple configuration.

[0090] In addition, in the present embodiment, the first optical element 41A is a lens having a plane-symmetrical shape with respect to a virtual center plane Vc1 intersecting the Z direction.

[0091] According to the above-described configuration, the first optical element 41A can be realized with a relatively simple configuration.

[0092] Furthermore, in this embodiment, the light emitting device 1A includes a third optical element 43A that collimates the laser light L having passed through the first optical element 41A in the Y direction (slow axis direction).

[0093] According to the above-described configuration, the laser light L can be collimated also in the Y direction.

[0094] [Second embodiment]

[0095] Figure 3 is a side view showing a light emitting device 1B according to a second embodiment. Figure 4 It is a plan view showing the light emitting device 1B.

[0096] If Figure 3 and Figure 1 to compare and Figure 4 and Figure 2A comparison clearly shows that the position of the third optical element 43B in this embodiment is different from the position of the third optical element 43A in the first embodiment. Specifically, in the first embodiment, the third optical element 43A is located on the opposite side of the first optical element 41A relative to the second optical element 42A. In contrast, in this embodiment, the third optical element 43B is located closer to the first optical element 41A relative to the second optical element 42A, that is, between the first optical element 41A and the second optical element 42A.

[0097] In this embodiment, as in the first embodiment described above, as an example, the third optical element 43B has a plane-symmetrical shape with respect to a virtual center plane Vc3, which is a plane intersecting and orthogonal in the Y direction. The incident surface 43a and the exit surface 43b of the third optical element 43B have generatrixes along the Z direction and cylindrical surfaces extending in the Z direction. The incident surface 43a is a plane orthogonal to the X direction. The exit surface 43b is a convex curved surface convex in the X direction.

[0098] In addition, the structure and arrangement of the first optical element 41A and the second optical element 42A in this embodiment are the same as those in the above-mentioned first embodiment.

[0099] As described above, in this embodiment, the third optical element 43B is located between the first optical element 41A and the second optical element 42A. Figure 3 As shown, in this embodiment, since the third optical element 43B is located between the first optical element 41A and the second optical element 42A, the laser light L can be collimated in the Y direction with a narrower beam width Wy. Therefore, according to this embodiment, the beam width Wyc of the collimated laser light L in the Y direction can be further reduced.

[0100] [Third embodiment]

[0101] Figure 5 1C is a side view showing a light emitting device according to a third embodiment. Figure 6 It is a plan view showing the light emitting device 1C.

[0102] If Figure 6 and Figure 2 to compare and Figure 5 and Figure 1A comparison clearly shows that the structure of the first optical element 41C in this embodiment differs from the structure of the first optical element 41A in the first embodiment. Specifically, in the first embodiment, the first optical element 41A is a lens having a plane-symmetric shape with respect to a virtual center plane Vc1, which is a plane intersecting and orthogonal to the Z direction. In contrast, in this embodiment, the first optical element 41C is a lens having an axisymmetric shape with respect to the central axis Ax along the optical axis.

[0103] The first optical element 41C is configured as a rotating body that rotates about a central axis Ax. The first optical element 41C is arranged so that the central axis Ax lies along the X direction and overlaps with the optical axis of the laser light L. The incident surface 41a and the exit surface 41b of the first optical element 41C each comprise a rotational surface that rotates about the central axis Ax extending in the X direction. The exit surface 41b is a convexly curved surface that protrudes in the X direction. The exit surface 41b protrudes further than the incident surface 41a.

[0104] Furthermore, in the present embodiment, the second optical element 42A is also arranged closer to the first optical element 41C than the convergence point Pcz in the Z direction of the laser light L generated by the first optical element 41C.

[0105] In addition, if Figure 6 As shown, although the convergence point Pcy of the laser light L in the Y direction appears between the first optical element 41C and the second optical element 42A, the energy density at the convergence point Pcy is not that high, so problems such as dust accumulation do not occur.

[0106] As described above, in the present embodiment, the first optical element 41C is a lens having an axisymmetric shape with respect to the central axis Ax along the optical axis of the laser light L.

[0107] According to this embodiment, the laser light L is also converged in a direction between the Z direction and the Y direction, thereby achieving effects such as reducing aberration of the laser light L. In addition, according to this embodiment, the first optical element 41C can be realized with a relatively simple structure.

[0108] [Fourth embodiment]

[0109] [Structure of light source unit]

[0110] Figure 7 is a plan view of a light source unit 100A (100) according to a fourth embodiment including a plurality of light emitting devices 1C according to the third embodiment. Figure 8 yes Figure 7 In addition, in Figure 8In FIG. 1 , the filter 102 , the reflective mirror 103 and the condenser lenses 104 and 105 are shown as a side view.

[0111] As an example, a light-emitting device 1C according to the third embodiment is mounted on a light source unit 100A. The light source unit 100A includes a base 101, multiple light-emitting devices 1C, multiple reflectors 103, condenser lenses 104 and 105, an optical filter 102, a housing base 106, and an optical fiber 107. The optical filter 102, reflector 103, and condenser lenses 104 and 105 are examples of optical components. Each light-emitting device 1C includes a light-emitting module 10, a first optical element 41C, a second optical element 42A, and a third optical element 43A.

[0112] The reflector 103 reflects light from the light emitting device 1C and traveling in the X direction toward the Y direction. The reflector 103 is an example of a deflecting member. The light reflected by the reflector 103 is condensed by condensing lenses 104 and 105 .

[0113] Here, if Figure 7 As shown, the subunits 100a including the light emitting device 1C (ie, the light emitting module 10, the first optical element 41C, the second optical element 42A, and the third optical element 43A) and the reflector 103 are arranged at substantially equal intervals in the Y direction. Figure 8 As shown in FIG. 1 , the plurality of subunits 100a are arranged to be staggered in the Z direction. The closer to the focusing lens 104, the shorter the distance in the Z direction from the bottom surface 101a of the base 101 of the subunit 100a. Figure 8 As shown, the surface 101b of the base 101 is provided with steps that deviate in the opposite direction of the Z direction as it moves toward the Y direction. Each step intersects and is orthogonal to the Z direction, and extends generally in the X and Y directions. The subunit 100a is mounted on each step of the surface 101b.

[0114] In the above-described configuration, light from each subunit 100a (each reflector 103) is arranged at equal intervals in the Z direction on the incident surface of the condenser lens 104. The light from each subunit 100a passes through the condenser lens 104, the filter 102, and the condenser lens 105 and is input to the input portion 107a of the optical fiber 107. The optical fiber 107 is supported by the optical fiber support portion 106a provided on the housing base 106.

[0115] In addition, the light emitting device 1C of the light source unit 100A can be replaced with the light emitting devices 1A and 1B of other embodiments.

[0116] Figure 9 41C is a top view showing the mounting structure of the first optical element 41C. Figure 9As shown, the first optical element 41C is fixed to the housing 20 of the light-emitting module 10 via the joint 50. With this structure, the housing 20 can be used to implement a relatively simple mounting structure for the first optical element 41C. The light-emitting module 10, including the housing 20, is mounted on the surface 101b and protrudes from the surface 101b in the Z direction. The light-emitting module 10 is an example of a protruding portion. The joint 50 can also be referred to as a fixing portion. The Z direction is an example of a direction intersecting the surface 101b.

[0117] The bonding portion 50 is, for example, an adhesive made of a synthetic resin material, or may be an electromagnetic wave curable adhesive or a thermosetting adhesive.

[0118] The joining portion 50 is interposed between the corner 21f between the side surfaces 21d on both sides in the Y direction and the front surface 21e in the X direction of the housing 20 and the peripheral edge of the first optical element 41C separated from the optical path of the laser beam, and joins the corner 21f and the peripheral edge.

[0119] The housing 20 and the first optical element 41C are bonded together via bonding portions 50 at a plurality of locations. Figure 9 The two joints 50 shown are spaced apart from each other in the Y direction. Figure 9 There is also a joint portion 50 (not shown) at a position where at least one of the two joint portions 50 shown is separated in the opposite direction of the Z direction, and the housing 20 and the first optical element 41C are joined by three or four joint portions 50. Figure 9 At least one of the two joining portions 50 shown extends to a certain extent in the opposite direction of the Z direction. In this case, the housing 20 and the first optical element 41C are joined by the two joining portions 50. Therefore, the housing 20 and the first optical element 41C can be joined by two or more joining portions 50.

[0120] Assuming that the first optical element 41C is cantilevered only by the joint 50 between the first optical element 41C and the surface 101b of the base 101, the optical axis of the laser light emitted from the first optical element 41C may deviate from the X direction in the Z direction or in the opposite direction of the Z direction due to a slight tilt (tilt) of the first optical element 41C with respect to the Z direction. In this case, the light from each subunit 100a (each reflector 103) enters the condenser lens 104 from the desired position in the Z direction to a position deviating from the Z direction, and the convergence of the laser light in the Z direction may be reduced.

[0121] In this regard, in the present embodiment, the first optical element 41C is joined to the housing 20 of the light-emitting module 10 via the joining portion 50. With this structure, since the housing 20 can support the first optical element 41C, it is possible to suppress tilting of the first optical element 41C with respect to the Z direction, thereby suppressing tilting of the laser light in the Z direction and reducing the convergence of the spatially coupled laser light in the Z direction.

[0122] Furthermore, as described above, in this embodiment, the first optical element 41C and the housing 20 are joined via a plurality of joining portions 50 spaced apart in the Z direction. This structure further suppresses tilting of the first optical element 41C with respect to the Z direction, further suppressing tilting of the laser light in the Z direction and a reduction in the convergence of the laser light. The base 101 is an example of a base, and the surface 101b is an example of a first surface.

[0123] Furthermore, in this embodiment, the joint 50 is interposed between the first optical element 41C and the housing 20 in the direction (X direction) along the central axis Ax (optical axis). With this structure, even if the joint 50 contracts or expands, the first optical element 41C can easily move parallel to the housing 20 in the X direction. In other words, the first optical element 41C is less likely to tilt.

[0124] Furthermore, in the present embodiment, a plurality of joints 50 are arranged so as to sandwich the central axis Ax. The fact that a plurality of joints 50 are arranged so as to sandwich the central axis Ax means that when viewed in the direction of the central axis Ax (the X direction), the plurality of joints 50 are arranged on opposite sides of each other with a virtual straight line (a virtual plane, not shown) passing through the central axis Ax sandwiched therebetween. According to the above-mentioned structure, even in the event that the joint 50 shrinks or expands, etc., the first optical element 41C becomes easy to move parallel to the X direction. In other words, the first optical element 41C becomes difficult to tilt. Furthermore, in the present embodiment, the plurality of joints 50 can be arranged at two or more locations that rotate around the central axis Ax when viewed in the X direction. According to the above-mentioned structure, even in the event that the joint 50 shrinks or expands, etc., the first optical element 41C becomes easy to move relative to the housing 20. In other words, the first optical element 41C becomes difficult to tilt.

[0125] Alternatively, the joint 50 may be expanded to a desired area along a virtual plane intersecting the X-direction, such as the YZ plane. In this case, even if the joint 50 were to shrink or expand, the larger the area, the easier it would be for the first optical element 41C to translate relative to the housing 20. In other words, the first optical element 41C would be less likely to tilt.

[0126] Figure 10 4 is a top view showing the mounting structure of the second optical element 42A. Figure 10 As shown, the second optical element 42A is attached to a post 101c protruding from the surface 101b in the Z direction via a joint 50. As an example, the post 101c has a quadrangular prism shape, but may also have other shapes such as a cylinder. The post 101c is an example of a protrusion. The post 101c is arranged on both sides of the second optical element 42A in the Y direction.

[0127] In addition, in this embodiment, Figure 10 There is another joining portion 50 (not shown) at a position spaced apart in the opposite direction of the illustrated joining portion 50 in the Z direction, and the terminal 101 c and the second optical element 42A are joined by the two joining portions 50 .

[0128] The terminal 101c may be attached to the surface 101b of the base 101 via a bonding material such as an adhesive or solder, may be soldered to the surface 101b of the base 101, may be attached to the surface 101b of the base 101 via a fixing tool such as a screw, or may be integrally formed with the base 101. The adhesive may be an electromagnetic wave curing adhesive or a thermosetting adhesive.

[0129] With the above-described structure, the terminal 101c can support the second optical element 42A, thereby suppressing tilt of the second optical element 42A with respect to the Z direction, thereby suppressing tilt of the laser light in the Z direction and reducing the convergence of the spatially coupled laser light in the Z direction. Furthermore, the third optical element 43A can also be supported by a terminal (not shown) similar to the terminal 101c.

[0130] [Fifth embodiment]

[0131] Figure 11 This is a top view of a portion of the light source unit 100B (100) according to the fifth embodiment, and is a diagram showing the mounting structure of the first optical element 41C. Figure 12 This is a rear view of the mounting structure of the first optical element 41C and the terminal 101c, that is, the first optical element 41C, as viewed in the X direction. Figure 11 、 12 Regarding the mounting structure of the first optical element 41C shown, the light source unit 100B has the same structure as the light source unit 100A of the fourth embodiment.

[0132] like Figure 11 、 12As shown in FIG. 1 , in this embodiment, the first optical element 41C is joined to a terminal post 101c protruding from the surface 101b in the Z direction via a plurality of joining portions 50. The terminal posts 101c are arranged on both sides of the first optical element 41C in the Y direction. In each terminal post 101c, two joining portions 50 are arranged spaced apart in the Z direction. The number of joining portions 50 in each terminal post 101c is not limited to two, but may be three. In addition, as Figure 12 As shown, the two joint portions 50 are arranged at the upper end and the lower end of the terminal 101 c , but the present invention is not limited thereto and the two joint portions 50 may be arranged at positions away from the upper end and the lower end of the terminal 101 c .

[0133] Furthermore, the first optical element 41C has an extension 41d extending radially outward from the optical axis at its center in the X direction (optical axis direction). The joint 50 is interposed between the end surface 41d1 of the extension 41d, which faces the opposite direction in the X direction, and the terminal 101c. This structure prevents the joint 50 from interfering with the optical path of the laser beam.

[0134] According to this embodiment, the first optical element 41C can also be supported by the terminal post 101c, thereby suppressing the tilt of the first optical element 41C relative to the Z direction, suppressing the tilt of the laser in the Z direction, and suppressing the reduction in the convergence of the spatially coupled laser in the Z direction.

[0135] [Sixth embodiment]

[0136] Figure 13 This is a rear view of the first optical element 41C and the terminal 101c of the sixth embodiment, that is, the mounting structure of the first optical element 41C, as viewed in the X direction. Figure 13 Regarding the mounting structure of the first optical element 41C shown, the light source unit 100C ( 100 ) has the same structure as the light source unit 100A of the fourth embodiment.

[0137] like Figure 13 As shown, in the present embodiment, the first optical element 41C and the terminal 101c are joined by a joint 50 extending in the Z direction. As in the present embodiment, the first optical element 41C and the terminal 101c (protrusion) are joined by a joint 50 extending in the Z direction. Thus, even in a structure that does not have a plurality of joints 50, the inclination of the first optical element 41C relative to the Z direction can be suppressed, and the inclination of the laser in the Z direction and the reduction in the convergence of the laser in the Z direction that has been spatially coupled can be suppressed. The length of the joint 50 in the Z direction can be any length that can suppress the inclination of the first optical element 41C, and is preferably more than 1 / 4 of the length of the first optical element 41C in the Z direction, and more preferably more than 1 / 3. In addition, the direction in which the joint 50 extends is not limited to the Z direction.

[0138] Furthermore, in this embodiment, the joint 50 is interposed between the first optical element 41C and the terminal 101c in the Y direction intersecting the central axis Ax. With this structure, even if the joint 50 contracts or expands, the first optical element 41C easily moves parallel to the terminal 101c in the Y direction. In other words, the second optical element 42A is less likely to tilt.

[0139] [Seventh embodiment]

[0140] Figure 14 This is a schematic structural diagram of a light source unit 100D (100) according to the seventh embodiment, and is a plan view of the interior of the light source unit 100D as viewed in the direction opposite to the Z direction.

[0141] like Figure 14 As shown, the light source unit 100D includes a base 101 , an optical fiber 107 fixed to the base 101 , a plurality of subunits 100 a each including a light emitting device 1C and a reflector 103 , and a light combining section 108 for combining laser beams from the subunits 100 a .

[0142] The optical fiber 107 is an output optical fiber, and is fixed to the base 101 via an optical fiber support portion 106 a that supports an end portion (not shown).

[0143] The optical fiber support portion 106a may be integrally formed with the base 101 as a part of the base 101, or the optical fiber support portion 106a may be a member separate from the base 101 and attached to the base 101 via a fixing tool such as a screw.

[0144] The base 101 also includes a portion corresponding to the housing base 106 in the fourth embodiment. The base 101 is made of a material with high thermal conductivity, such as copper or aluminum. Furthermore, the base 101 is covered by a housing (not shown). The optical fiber 107, subunit 100a, optical combiner 108, and optical fiber support 106a are housed in a sealed housing formed between the base 101 and the housing.

[0145] On the surface 101b of the base 101, similarly to the fourth embodiment, a step is provided so that the position of the subunit 100a deviates in the opposite direction of the Z direction as it moves toward the Y direction (see Figure 8In each of arrays A1 and A2, where a plurality of subunits 100a are arranged at predetermined intervals (e.g., fixed intervals) in the Y direction, the subunits 100a are positioned at each height difference. Therefore, the Z-direction positions of the subunits 100a included in array A1 deviate in the opposite direction of the Z direction as they move in the Y direction, and the Z-direction positions of the subunits 100a included in array A2 also deviate in the opposite direction of the Z direction as they move in the Y direction.

[0146] The laser beams output from the light emitting modules 10 of the plurality of subunits 100a are combined by the optical combiner 108. The optical combiner 108 includes optical components such as a combiner 108a, a reflector 108b, and a half-wave plate 108c.

[0147] Reflector 108b directs laser light from subunit 100a of array A1 through half-wavelength plate 108c toward combiner 108a. Half-wavelength plate 108c rotates the polarization plane of light from array A1. Laser light from subunit 100a of array A2 is directly input to combiner 108a.

[0148] The combiner 108a combines the light from the two arrays A1 and A2 and outputs the combined light toward the condenser lens 104. The combiner 108a can also be called a polarization combining element.

[0149] Furthermore, a refrigerant passage 109 is provided on the base 101 for cooling the subunit 100a (light-emitting module 10), the optical fiber support 106a, the focusing lenses 104 and 105, the combiner 108a, and the like. A refrigerant, such as a cooling liquid, flows through the refrigerant passage 109. The refrigerant passage 109 flows near, for example, directly below or near, the mounting surfaces of the components of the base 101. The inner surface of the refrigerant passage 109 and the refrigerant within the refrigerant passage 109 (not shown) are thermally connected to the components or locations to be cooled, namely, the subunit 100a (light-emitting module 10), the optical fiber support 106a, the focusing lenses 104 and 105, the combiner 108a, and the like. Heat is exchanged between the refrigerant and the components or locations via the base 101, thereby cooling the components. In addition, as an example, the inlet 109 a and the outlet 109 b of the coolant passage 109 are provided at the ends of the base 101 in the opposite direction in the Y direction, but may be provided at other positions.

[0150] like Figure 14As shown, in subunit 100a1 (100a) of array A1, laser light directed in the X1 direction is reflected in the Y direction by reflector 103. In subunit 100a2 (100a) of array A2, laser light directed in the X2 direction, which is opposite to the X1 direction, is reflected in the Y direction by reflector 103. Subunit 100a1 is an example of a first subunit, and subunit 100a2 is an example of a second subunit. Furthermore, the X1 direction is an example of a first direction, and the X2 direction is an example of a direction opposite to the first direction.

[0151] In this way, if laser light is traveling in opposing directions in subunit 100a1 of array A1 and subunit 100a2 of array A2, leakage light from the laser light traveling in a direction closer to the other array within subunit 100a of one of arrays A1 and A2 may interfere with the laser light within subunit 100a of the other array. Furthermore, as in the fourth to sixth embodiments described above, if optical components such as first optical element 41C, second optical element 42A, and third optical element 43A are connected to base 101 via a joint 50, there is a risk that leakage light will be directed toward this joint 50, potentially damaging it. Leakage light can arise from, for example, laser light that is unintentionally reflected or transmitted through the optical components.

[0152] Therefore, in this embodiment, a shielding portion 101d1 is provided between the array A1 and the array A2 to shield light leakage.

[0153] Figure 15 This is a side view of the shielding portion 101d1. The shielding portion 101d1 protrudes from the surface 101b in the Z direction. The position of the top of the shielding portion 101d1 in the Z direction, that is, the height from the surface 101b, is set to a height sufficient to block the leakage light L1 indicated by the dashed arrow. For example, the position of the top of the shielding portion 101d1 in the Z direction is at least the same as the position of the tops of the first optical element 41C, the second optical element 42A, and the third optical element 43A included in the subunit 100a in the Z direction, or is located further in front of the tops in the Z direction.

[0154] The shielding portion 101d1 may be attached to the surface 101b of the base 101 via a bonding material such as an adhesive or solder, may be welded to the surface 101b of the base 101, may be attached to the surface 101b of the base 101 via a fixing tool such as a screw, or may be integrally formed with the base 101. The adhesive may be an electromagnetic wave curable adhesive or a thermosetting adhesive, and an adhesive with relatively high thermal conductivity is preferred.

[0155] Furthermore, in this embodiment, the shielding portion 101d1 has reflective surfaces 101da at both ends in the X1 direction and the X2 direction. The reflective surfaces 101da reflect the leaked light L1 in a direction opposite to the incident direction of the leaked light L1. Specifically, the reflective surface 101da, on which the leaked light L1 traveling in the X2 direction is incident, reflects the leaked light L1 in a direction away from the X1 direction, or in other words, in a direction oblique to the X1 direction. Furthermore, the reflective surface 101da, on which the leaked light L1 traveling in the X1 direction is incident, reflects the leaked light L1 in a direction away from the X2 direction, or in other words, in a direction oblique to the X2 direction. In other words, the reflective surface 101da distorts the leaked light L1 in either the X1 or X2 direction. This prevents the reflected light of the leaked light L1 from interfering with the laser light transmitted within the subunit 100a. Furthermore, the reflecting surface 101da is tilted so as to face one of the X1 and X2 directions as it faces the Z direction, but the tilt direction is not limited thereto. Furthermore, the reflecting surface 101da may be, for example, a curved surface. Furthermore, if it is a curved surface, the reflecting surface 101da may be spherical or cylindrical.

[0156] [Eighth Embodiment]

[0157] Figure 16 This is a side view (partial cross-sectional view) of the shielding portion 101d2 included in the light source unit 100E (100) of the eighth embodiment. Figure 15 The shielding portion 101d1 shown is provided Figure 16 The light source unit 100E has the same structure as the light source unit 100D of the seventh embodiment except for the shielding portion 101d2 shown.

[0158] In this embodiment, the reflective surface 101da of the shielding portion 101d2 is coated with a coating, such as black paint, that converts laser energy into heat. In this case, the reflective surface 101da functions as an absorption surface that absorbs the laser energy. The reflective surface 101da is an example of an absorption surface. This structure further reduces the intensity of the light reflected from the reflective surface 101da, thereby further minimizing the adverse effects of the reflected light on other parts within the light source unit 100D.

[0159] In addition, if Figure 16 As shown, a refrigerant passage 109 through which refrigerant C flows is provided in the base 101 so as to overlap with the shielding portion 101d2 in the Z direction. The refrigerant passage 109 is provided so that a portion of the section from the inlet 109a to the outlet 109b of the refrigerant passage 109 passes through a position overlapping with the shielding portion 101d2 in the Z direction. In this section, the refrigerant passage 109 extends, for example, in the Y direction along the shielding portion 101d2.

[0160] The shielding portion 101d2 and the base 101 are made of a material with high thermal conductivity, such as a copper-based material or an aluminum-based material, and the shielding portion 101d2 is thermally connected to the inner surface of the refrigerant passage 109 and the refrigerant C. Thus, according to this embodiment, heat is exchanged between the refrigerant C and the shielding portion 101d2 via the shielding portion 101d2 and the base 101, and the shielding portion 101d2 that has generated heat based on the energy of the leakage light L1 is cooled, thereby suppressing a temperature increase in the shielding portion 101d2 and its surroundings.

[0161] [Ninth embodiment]

[0162] Figure 17 This is a top view of a subunit 100a1 (100a) included in a light source unit 100F (100) of the ninth embodiment. Figure 14 The subunit 100a shown is provided with Figure 17 The light source unit 100F has the same structure as the light source unit 100D of the seventh embodiment except for the subunit 100a shown. Figure 17 The subunit 100a1 of array A1 is shown, but the subunit 100a2 of array A2 also has and Figure 17 The same structure, that is, with Figure 17 The structure is in a mirror image relationship.

[0163] like Figure 17 As shown, the second optical element 42A is bonded to the connecting post 101c via the bonding portion 50. The connecting post 101c is provided on both sides of the second optical element 42A in the Y direction, but may be provided on only one side.

[0164] Furthermore, a shielding portion 101d3 is provided at a position spaced apart in the X1 direction from the joint 50. This configuration prevents leakage light L1 from the subunit 100a of the other of the arrays A1 and A2 from irradiating the joint 50 included in the subunit 100a of one of the arrays A1 and A2, thereby damaging the joint 50. This embodiment allows the shielding portion 101d3 to be implemented with a more compact structure.

[0165] Figure 18 is a side view of the shielding portion 101d3. Figure 18As shown, in this embodiment, shielding portion 101d3 also has a reflective surface 101da similar to that of the seventh embodiment. The direction of reflection of leakage light L1 by reflective surface 101da is the same as that of the seventh embodiment. This prevents the reflected light of leakage light L1 from reflective surface 101da from interfering with the laser light propagating within subunit 100a. Furthermore, shielding portion 101d3 can also have the same structure as that of the eighth embodiment and function as an absorber.

[0166] [Tenth embodiment]

[0167] Figure 19 This is a top view of the subunit 100a included in the light source unit 100G (100) of the tenth embodiment. Figure 14 The subunit 100a shown is provided with Figure 19 The light source unit 100G has the same structure as the light source unit 100D of the seventh embodiment except for the subunit 100a shown. Figure 19 The subunit 100a1 of array A1 is shown, but the subunit 100a2 of array A2 also has and Figure 17 The same structure, i.e. with Figure 17 The structure is in a mirror image relationship.

[0168] like Figure 19 As shown, the second optical element 42A is joined to the shielding portion 101d3 via the joint 50. In addition, the joint 50 is provided on the opposite side of the light leakage relative to the shielding portion 101d3. Therefore, in this embodiment, the shielding portion 101d3 also shields the light leakage L1 toward the joint 50. That is, the shielding portion 101d3 can be said to be a component that functionally integrates the terminal 101c and the shielding portion 101d3 in the structure of the ninth embodiment. Even according to this embodiment, the shielding portion 101d3 can suppress the phenomenon that the light leakage L1 from the sub-unit 100a of the other array among the arrays A1 and A2 is irradiated to the joint 50 included in the sub-unit 100a of one array among the arrays A1 and A2, thereby damaging the joint 50. According to this embodiment, a structure that can suppress the light leakage L1 from irradiating the joint 50 and suppressing the tilt of the second optical element 42A can be realized with a simpler structure.

[0169] [Eleventh embodiment]

[0170] [Light source device, fiber laser structure]

[0171] Figure 20This is a structural diagram of a light source device 110 according to an eleventh embodiment, in which any of the light source units 100 described in the fourth to tenth embodiments is installed. The light source device 110 includes a plurality of light source units 100 as excitation light sources. Light (laser) emitted from the plurality of light source units 100 propagates toward the combiner 90, which serves as an optical coupling unit, via an optical fiber 107. The output ends of the optical fibers 107 are respectively coupled to the plurality of input ports of the multi-input, multi-output combiner 90. In addition, the light source device 110 is not limited to a structure having a plurality of light source units 100; it is sufficient as long as it has at least one light source unit 100.

[0172] [Twelfth embodiment]

[0173] Figure 21 It is installed Figure 20 The fiber laser 200 is a structural diagram of the light source device 110. The fiber laser 200 has Figure 20 The light source device 110 and the coupler 90 are shown, along with a rare-earth-doped optical fiber 130 and an output-side optical fiber 140. High-reflection FBRs 120 and 121 (fiber brag gratings) are provided at the input and output ends of the rare-earth-doped optical fiber 130, respectively.

[0174] The output end of combiner 90 is connected to the input end of rare-earth-doped optical fiber 130, and the output end of rare-earth-doped optical fiber 130 is connected to the input end of output-side optical fiber 140. Alternatively, the input portion for causing the laser light outputted from the plurality of light source units 100 to enter the rare-earth-doped optical fiber 130 may employ another structure, instead of combiner 90. For example, the optical fibers 107 of the output portions of the plurality of light source units 100 may be arranged in a row, and the laser light outputted from the plurality of optical fibers 107 may be incident upon the input end of the rare-earth-doped optical fiber 130 using an optical system including a lens or the like. Rare-earth-doped optical fiber 130 is an example of an optical amplification optical fiber.

[0175] According to the light source unit 100 , the light source device 110 , and the fiber laser 200 described above, by including the light emitting device 1C or the light emitting devices 1A and 1B, advantages such as further narrowing of the beam width or optical diameter can be achieved.

[0176] The above examples illustrate embodiments of the present invention, but the above embodiments are merely examples and are not intended to limit the scope of the invention. The above embodiments can be implemented in various other ways and can be omitted, replaced, combined, or modified without departing from the main purpose of the invention. In addition, the specifications (structure, type, direction, model, size, length, width, thickness, height, number, configuration, position, material, etc.) of various structures and shapes can be appropriately changed and implemented.

[0177] For example, the first optical element, the second optical element, and the third optical element are not limited to the structures disclosed in the embodiments, and may be other optical elements capable of reflecting, refracting, or diffracting light, such as mirrors, prisms, or diffractive optical elements. Furthermore, the diffractive optical element may be, for example, a structure in which multiple diffraction gratings having different periods are composited and integrated.

[0178] Furthermore, the optical axis of the light path from the light emitting element to the third optical element does not need to be linear, and may be curved as appropriate.

[0179] The arrangement of the subunits, light emitting modules, optical elements, light combining unit, optical components, protrusions, shielding units, etc. in the light source is not limited to the above-described embodiment. Furthermore, the direction of leakage light is not limited to the above-described direction.

[0180] -Industrial Applicability-

[0181] The present invention is applicable to a light emitting device, a light source unit, a light source device, and a fiber laser.

[0182] -Explanation of Symbols-

[0183] 1A, 1B, 1C...light-emitting device

[0184] 10...Light-emitting module (protrusion)

[0185] 11...Window components

[0186] 20...housing

[0187] 21...Wall components

[0188] 21a...base

[0189] 21b...Opening

[0190] 21c...top

[0191] 21d...side

[0192] 21e...front

[0193] 21f..corner

[0194] 22...Window components

[0195] 30...Light-emitting unit

[0196] 31...Abutment

[0197] 31a...top surface

[0198] 32...Light-emitting element

[0199] 41A, 41C...first optical element

[0200] 41a...Incident surface

[0201] 41b...Exit surface

[0202] 41d...Extension

[0203] 41d1...end face

[0204] 42A...Second optical element

[0205] 42a...Incident surface

[0206] 42b...Exit surface

[0207] 43A, 43B...third optical element

[0208] 43a...Incident surface

[0209] 43b...Exit surface

[0210] 50...Joint

[0211] 90...combiner

[0212] 100, 100A~100G...Light source unit

[0213] 100a...subunit

[0214] 100a1...subunit (first subunit)

[0215] 100a2...subunit (second subunit)

[0216] 101...base

[0217] 101a... bottom

[0218] 101b...Surface

[0219] 101c...Binding post (protrusion)

[0220] 101d1, 101d2, 101d3... shielding part

[0221] 101da...Reflective surface (absorption surface)

[0222] 102...Filter

[0223] 103...Reflector

[0224] 104, 105...condenser lens

[0225] 106...Housing base

[0226] 106a...Optical fiber support portion

[0227] 107...Fiber optic

[0228] 107a...Input

[0229] 108...Photosynthesis Department

[0230] 108a...combiner

[0231] 108b...reflector

[0232] 108c...1 / 2 wavelength plate

[0233] 109...Refrigerant passage

[0234] 109a...Entrance

[0235] Exit 109b...

[0236] 110...Light source device

[0237] 120, 121...High reflective FBR

[0238] 130...Rare earth added optical fiber

[0239] 140...Output side optical fiber

[0240] 200...Fiber laser

[0241] Ax...Center axis

[0242] A1, A2... array

[0243] C...Refrigerant

[0244] L...Laser

[0245] Lv...Laser

[0246] L1...light leakage

[0247] Pcy...Convergence Point

[0248] Pcz...Convergence point

[0249] Vc1, Vc2, Vc3...virtual center plane

[0250] Wz, Wz1, Wz2... beam width

[0251] Wyc...(collimated) beam width

[0252] Wzc...(collimated) beam width

[0253] X...direction

[0254] X1...direction (first direction)

[0255] X2...direction (opposite direction to the first direction)

[0256] Y...direction

[0257] Z...direction.

Claims

1. A light-emitting device comprising: A light emitting element having a fast axis and a slow axis and emitting laser light; a housing for housing the light emitting element and provided with a window through which the laser light emitted from the light emitting element passes; a first optical element disposed outside the housing and configured as an optical element having an incident surface and an exit surface for incident laser light from only one of the light-emitting elements, wherein the laser light having a beam width in the fast axis direction expanding as it passes through the window is incident on the incident surface, and the laser light having a beam width in the fast axis direction narrowing as it passes from the exit surface is emitted; a second optical element for collimating the laser light having passed through the first optical element in the fast axis direction in a state where the beam width in the fast axis direction is narrower than the beam width in the fast axis direction at the incident surface of the first optical element, the second optical element being arranged closer to the first optical element than to a convergence point of the laser light in the fast axis direction of the first optical element; as well as The third optical element collimates, in a slow axis direction, the laser light whose beam width in the slow axis direction is expanded as it passes through the first optical element.

2. The light emitting device according to claim 1, wherein The first optical element is a convex lens at least in the fast axis direction, The second optical element is a concave lens at least in the fast axis direction.

3. The light emitting device according to claim 1 or 2, wherein: The first optical element is a lens having a plane-symmetrical shape with respect to a virtual center plane intersecting the fast axis direction of the laser light.

4. The light emitting device according to claim 1 or 2, wherein: The first optical element is a lens having an axisymmetric shape with respect to a central axis along the optical axis of the laser light. The light emitting device according to claim 1 , wherein: The third optical element is arranged between the first optical element and the second optical element.

6. The light emitting device according to claim 1 or 2, wherein: The light emitting device comprises: a base having a surface substantially along the optical axis direction of the laser light; The first optical element and the second optical element are located on the surface, At least one of the first optical element and the second optical element is fixed to a protrusion protruding from the surface via a bonding portion.

7. The light emitting device according to claim 6, wherein: At least one of the first optical element and the second optical element is fixed to the protruding portion via the joining portions at a plurality of locations.

8. The light emitting device according to claim 6, wherein The joining portion is interposed between at least one of the first optical element and the second optical element and the protruding portion in a direction along the optical axis.

9. The light emitting device according to claim 6, wherein: The joining portion is interposed between at least one of the first optical element and the second optical element and the protruding portion in a direction intersecting the optical axis.

10. The light emitting device according to claim 6, wherein The protrusion is the light emitting element.

11. The light emitting device according to claim 6, wherein The light emitting device includes a shielding portion that shields leakage of the laser light toward the joining portion.

12. The light emitting device according to claim 11, wherein The shielding portion includes a reflecting portion that reflects the leaked light in a direction opposite to an incident direction of the leaked light.

13. The light emitting device according to claim 11 or 12, wherein: The shielding portion includes an absorbing portion that absorbs energy of the leaked light.

14. The light emitting device according to claim 1 or 2, wherein: The first optical element is fixed to the light emitting element.

15. The light emitting device according to claim 1 or 2, wherein: The housing is hermetically sealed.

16. A light source unit comprising: The light-emitting device according to any one of claims 1 to 15; and The optical component guides the light emitted from the light emitting device to the input portion of an optical fiber.

17. The light source unit according to claim 16, wherein The light source unit comprises: A first subunit includes the light emitting element emitting laser light in a first direction, and the first optical element and the second optical element transmitting the laser light from the light emitting element in the first direction; a second subunit including the light-emitting element disposed away from the first subunit in the first direction and emitting laser light in a direction opposite to the first direction, and the first and second optical elements transmitting the laser light from the light-emitting element in a direction opposite to the first direction; as well as The shielding portion shields at least one of leakage light of the laser beam from the first subunit and leakage light of the laser beam from the second subunit.

18. The light source unit according to claim 17, wherein The shielding portion is located between the first subunit and the second subunit.

19. A light source device comprising: The light source unit according to any one of claims 16 to 18.

20. A fiber laser comprising: The light source device according to claim 19; and The optical amplifying optical fiber amplifies the laser light emitted from the light source device.

Images