Housing for optical device, optical device, laser welding device, and laser welding method

Abstract

To provide a housing of an optical device which is new and improved so that a problem caused by laser welding further hardly occurs when manufacturing the housing of an optical device by, for example, laser-welding a plurality of members, and provide the optical device, a laser welder and a laser welding method.SOLUTION: A housing of an optical device comprises: a plate-shaped first member having a first outer surface and a first end edge; a plate-shaped second member having a second outer surface and a second end edge extending along the first end edge; and a linear weld part which is obtained by welding a portion between the first outer surface and the second outer surface out of a boundary portion between the first end edge and the second end edge. The weld part extends from a clearance between the first outer surface and the second outer surface in a second direction intersecting with a first direction along the first outer surface and the first end edge, and the boundary portion includes an opposing zone which extends in a third direction intersecting with the first direction and the second direction as an opposing zone in which the first end edge and the second end edge face each other with an interval between the weld part and an accommodation chamber or contact with each other.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a housing for an optical device, an optical device, a laser welding device, and a laser welding method. [Background technology]

[0002] Conventionally, optical devices in which optical components are housed in a box-shaped housing are known (for example, see Patent Document 1). In Patent Document 1, the housing is made by joining a plurality of members together. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-131585 Summary of the Invention [Problem to be solved by the invention]

[0004] In this type of optical device, if spatter occurs when multiple components are laser welded together to create a housing, there is a risk that the spatter will fly to other parts of the housing, damaging its appearance, or that the spatter will enter the housing and affect the optical components.

[0005] Therefore, one of the objects of the present invention is to provide an improved and new optical device housing, optical device, laser welding apparatus, and laser welding method that are less likely to cause problems due to laser welding, for example, when manufacturing an optical device housing by laser welding multiple components. [Means for solving the problem]

[0006] The housing of the optical device of the present invention is, for example, a housing of an optical device that forms an accommodating chamber for an optical component, and comprises a plate-shaped first member having a first outer surface that forms the outer surface of the housing and a first edge, a plate-shaped second member having a second outer surface that forms the outer surface of the housing and a second edge extending along the first edge, and a linear weld formed by welding a portion of the boundary portion between the first edge and the second edge between the first outer surface and the second outer surface, the weld extending from between the first outer surface and the second outer surface in a second direction that intersects with a first direction along the first outer surface and the first edge, and the boundary portion includes an opposing section extending in a third direction that intersects with the first direction and the second direction, between the weld and the accommodating chamber, where the first edge and the second edge face or are in contact with each other with a gap between them.

[0007] In the housing for the optical device, the boundary portion may include an intermediate chamber in which the distance between the first edge and the second edge in a cross section intersecting with the first direction is greater than in other portions.

[0008] In the housing of the optical device, the maximum value of the distance may be 0.2 mm or more in a cross section intersecting with the first direction.

[0009] In the housing for the optical device, the boundary portion may include, as the opposing section, a plurality of opposing sections that are arranged in series between the welded portion and the accommodating chamber and extend in different directions from each other.

[0010] In the housing for the optical device, the first edge and the second edge may be in contact with each other in at least a part of the opposing section.

[0011] In the housing of the optical device, the boundary portion may include, as the opposing section, an opposing section extending approximately along the thickness direction of one of the first member and the second member for a length equal to or greater than half the thickness of the one member.

[0012] In the housing for the optical device, the deviation between the first outer surface and the second outer surface in the second direction may be 0.1 mm or less.

[0013] In the housing of the optical device, the welded portion may be provided circumferentially.

[0014] In the housing of the optical device, the chamber may be hermetically sealed at the welded portion.

[0015] In the housing of the optical device, the first member may be a member constituting a lid of the housing that closes an opening in a peripheral wall of the housing, the second member may be a member constituting the peripheral wall, the first edge may be a peripheral edge of the lid, and the second edge may be a peripheral edge of the peripheral wall that extends along the first edge.

[0016] Moreover, the optical device of the present invention includes, for example, a housing of the optical device and an optical component accommodated in the accommodation chamber.

[0017] The laser welding apparatus of the present invention is, for example, a housing for an optical device that constitutes an accommodating chamber for an optical component, and includes a plate-like first member having a first outer surface that becomes the outer surface of the housing and a first edge, and a plate-like second member having a second outer surface that becomes the outer surface of the housing and a second edge extending along the first edge, wherein a boundary portion between the first edge and the second edge includes a first opposing section that extends from between the first outer surface and the second outer surface in a second direction that intersects with a first direction along the first outer surface and the first edge, and a first opposing section that is interposed between the first opposing section and the accommodating chamber, and wherein the first edge and the second edge face each other with a gap therebetween or are in close contact with each other. a housing configured to include a second opposing section extending at least partially in a third direction intersecting the first direction and the second direction, and a laser welding device configured to irradiate a laser beam onto the housing to weld the first edge and the second edge, the laser welding device comprising a laser oscillator and an optical head that emits laser beam from the laser oscillator, the laser beam including at least one main beam and at least one sub-beam having a power density lower than that of the main beam, and a linear weld that is adjacent to the first outer surface and the second outer surface is formed by irradiating and sweeping the laser beam toward the first opposing section.

[0018] The laser welding apparatus may include a beam shaper that shapes the laser beam.

[0019] The laser welding method of the present invention may also be applied to, for example, a housing of an optical device that constitutes an accommodation chamber for an optical component, the housing comprising: a plate-like first member having a first outer surface that becomes the outer surface of the housing and a first edge; and a plate-like second member having a second outer surface that becomes the outer surface of the housing and a second edge extending along the first edge, wherein a boundary portion between the first edge and the second edge includes a first opposing section that extends from between the first outer surface and the second outer surface in a second direction intersecting with a first direction along the first outer surface and the first edge; A laser welding method for welding the first edge and the second edge by irradiating laser light to the housing, the housing being configured to include a second opposing section that faces or abuts the second edge with a gap and extends in a third direction that at least partially intersects the first direction and the second direction, wherein the laser light includes at least one main beam and at least one sub-beam having a lower power density than the main beam, and the laser light is irradiated and swept toward the first opposing section to form a linear weld adjacent to the first outer surface and the second outer surface. [Effects of the Invention]

[0020] The present invention provides a new and improved optical device housing, optical device, laser welding apparatus, and laser welding method. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is an exemplary schematic side view (partial cross-sectional view) showing the internal configuration of the optical device of the first embodiment. [Figure 2] FIG. 2 is an enlarged view of part II in FIG. [Figure 3] FIG. 3 is an exemplary schematic cross-sectional view of a welding structure formed on a housing of an optical device according to a first modified example of the first embodiment, taken at the same position as in FIG. [Figure 4] FIG. 4 is an exemplary schematic cross-sectional view of a welding structure formed on a housing of an optical device according to a second modified example of the first embodiment, taken at the same position as in FIG. [Figure 5] FIG. 5 is an exemplary schematic cross-sectional view of a welding structure formed on a housing of an optical device according to a third modified example of the first embodiment, taken at the same position as in FIG. [Figure 6] FIG. 6 is an exemplary schematic cross-sectional view of a welding structure formed on a housing of an optical device according to a fourth modified example of the first embodiment, taken at the same position as in FIG. [Figure 7] FIG. 7 is an exemplary schematic configuration diagram of a laser welding device according to the second embodiment. [Figure 8] FIG. 8 is an explanatory diagram showing the concept of the principle of the diffractive optical element included in the laser welding device of the second embodiment. [Figure 9] FIG. 9 is a schematic diagram showing an example of a beam (spot) on the surface of an object of the laser welding device of the second embodiment. [Figure 10] FIG. 10 is a schematic diagram showing another example of a beam (spot) on the surface of an object of the laser welding apparatus according to the second embodiment. [Figure 11] FIG. 11 is a schematic diagram showing yet another example of a beam (spot) on the surface of an object of the laser welding apparatus according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] Exemplary embodiments and modifications of the present invention are disclosed below. The configurations of the embodiments and modifications shown below, as well as the actions and results (effects) brought about by these configurations, are merely examples. The present invention can also be realized by configurations other than those disclosed in the following embodiments and modifications. Furthermore, according to the present invention, it is possible to obtain at least one of the various effects (including derivative effects) obtained by the configurations.

[0023] The following embodiments and modifications have similar configurations. The configurations of each embodiment and modification provide similar actions and effects based on the similar configurations. In the following, similar configurations are given similar reference numerals, and redundant descriptions may be omitted.

[0024] In this specification, ordinal numbers are given for convenience to distinguish between parts, portions, directions, etc., and do not indicate priority or order.

[0025] In each drawing, the X direction is represented by an arrow X, the Y direction is represented by an arrow Y, and the Z direction is represented by an arrow Z. The X direction, Y direction, and Z direction intersect with each other and are perpendicular to each other.

[0026] [First embodiment] Fig. 1 is a side view showing the internal configuration of an optical device 1 according to a first embodiment. As shown in Fig. 1, the optical device 1 includes a housing 10 and components housed within the housing 10, such as a temperature control device 20, a light-emitting element 41, a lens 42, a carrier 43, an optical isolator 51, a beam splitter 52, and a light-receiving element 53. The light-receiving element 53 is, for example, a photodiode.

[0027] Housing 10 has walls including a top wall 11, a bottom wall 12, two side walls 13, and two side walls 14. Housing 10 has, for example, a rectangular parallelepiped, box-like shape. Inside housing 10, a storage chamber R is formed that is surrounded by top wall 11, bottom wall 12, two side walls 13, and two side walls 14.

[0028] The bottom wall 12 extends in a direction intersecting the Z direction. In this embodiment, the bottom wall 12 extends in the X direction and the Y direction and is perpendicular to the Z direction.

[0029] In the accommodation chamber R, optical components are attached to the bottom wall 12 via a temperature control device 20. The optical components may be attached to the temperature control device 20 via a base plate made of ceramic such as aluminum oxide (Al2O3) or aluminum nitride (AlN). The bottom wall 12 may also be referred to as a support portion or a support wall.

[0030] The top wall 11 extends in a direction intersecting the Z direction. In this embodiment, the top wall 11 extends in the X direction and the Y direction and is perpendicular to the Z direction.

[0031] The side walls 13 each extend in a direction intersecting the X direction. In this embodiment, the side walls 13 extend in the Y direction and the Z direction and are perpendicular to the X direction. The side walls 13 are located at the ends of the housing 10 in the X direction (longitudinal direction).

[0032] An optical window 15 is provided in one of the side walls 13 .

[0033] Furthermore, a feedthrough 16 is provided in the other side wall 13 on which the optical window 15 is not provided, penetrating the side wall 13 in the thickness direction (X direction). It can be said that the feedthrough 16 also constitutes a part of the housing 10. The feedthrough 16 may have a portion penetrating the side wall 14.

[0034] The side walls 14 extend in a direction intersecting the Y direction. In this embodiment, the side walls 14 extend in the X and Z directions and are perpendicular to the Y direction. The side walls 14 are located at the ends of the housing 10 in the width direction. The side walls 13 and 14 may also be referred to as peripheral walls.

[0035] Top wall 11 may be made of a metal material such as Kovar, FeNi, or aluminum. A plating layer of Ni, NiAu, NiPtAu, NiPdAu, or the like may be provided on the surface of top wall 11. Furthermore, a brazing layer of silver, AuSn, or the like may be provided on the surfaces of top wall 11 that are to be joined to side walls 13 and 14.

[0036] The side walls 13, 14 may be made of a metal material such as Kovar. The surfaces of the side walls 13, 14 may be provided with a plating layer of Ni, NiAu, NiPtAu, NiPdAu, or the like. The surfaces of the side walls 13, 14 that bond with the top wall 11 may be provided with a brazing material layer of silver, AuSn, or the like. Alternatively, only the portions of the side walls 13, 14 that include the surfaces that bond with the top wall 11 may be made of a metal material, with the remaining portions being made of a ceramic such as aluminum oxide or aluminum nitride. The plating layer or brazing material layer is not essential for the top wall 11 and the side walls 13, 14.

[0037] The bottom wall 12 may be made of a metallic material such as a Cu-tungsten alloy or a CuMo alloy.

[0038] The feedthrough 16 may also be made of a ceramic, such as aluminum oxide or aluminum nitride.

[0039] The temperature adjustment device 20 has an upper substrate 21U, a lower substrate 21L, and a plurality of thermoelectric elements 22. The upper substrate 21U and the lower substrate 21L are arranged along the bottom wall 12. The thermoelectric elements 22 are respectively interposed between the upper substrate 21U and the lower substrate 21L.

[0040] The upper substrate 21U extends across the Z direction and has an upper surface 20a and a lower surface 21b behind the upper surface 20a. The upper substrate 21U may be made of an insulating material with high thermal conductivity, such as ceramic. Optical components such as the light-emitting element 41, lens 42, optical isolator 51, beam splitter 52, and light-receiving element 53 are mounted on the upper surface 20a directly or indirectly via other components such as a base plate. The upper substrate 21U may also be referred to as a first substrate or a mounting substrate, and the upper surface 20a may also be referred to as a mounting surface.

[0041] The lower substrate 21L extends intersecting the Z direction and has an upper surface 21a and a lower surface 20b behind the upper surface 21a. The lower substrate 21L may be made of an insulating material with high thermal conductivity, such as ceramic. The lower substrate 21L is attached to the bottom wall 12 of the housing 10 while being thermally connected to the bottom wall 12. The lower substrate 21L may also be referred to as a second substrate or a mounting substrate, and the lower surface 20b may also be referred to as a contact surface or a mounting surface.

[0042] The thermoelectric element 22 is an example of a semiconductor element, and can be made of a P-type semiconductor or an N-type semiconductor, such as a bismuth telluride-based semiconductor.

[0043] Wiring patterns (not shown) are provided on the lower surface 21b of the upper substrate 21U and the upper surface 21a of the lower substrate 21L. The thermoelectric elements 22 are respectively interposed between these two wiring patterns. The wiring patterns can be made of a highly conductive metal material, such as a copper-based metal.

[0044] The plurality of thermoelectric elements 22 are connected in series via a wiring pattern to form a PN junction. The plurality of thermoelectric elements 22 generate or absorb heat in response to a supply of power from outside the temperature adjustment device 20 via the wiring pattern. The heat generation and absorption in the thermoelectric elements 22 are switched depending on the direction of the current flowing through the plurality of thermoelectric elements 22. The wiring pattern may also be referred to as a conductor or a conductor layer.

[0045] In this way, the temperature adjustment device 20 functions as a base for the optical components and adjusts the temperature of the optical components by heating or cooling them. The temperature adjustment device 20 may also be called a Peltier module or a thermoelectric module.

[0046] The light-emitting element 41, which is an optical functional element, is, for example, a semiconductor laser element, and in this case, the optical device 1 is a wavelength-tunable laser module. Alternatively, the optical element may be an optical modulator element and the optical device may be an optical modulator module, or the optical element may be a photodiode and the optical device may be an optical receiver module, or an integrated coherent-transmitter-receiver optical subassembly (IC-TROSA) in which a semiconductor laser element, a photodiode element, and an optical modulator element are integrated. The light-emitting element 41 is mounted on the upper surface 20a of the temperature control device 20 via a carrier 43. The carrier 43 is made of an insulating material with a linear expansion coefficient close to that of the light-emitting element 41 or an insulating material with high thermal conductivity, and transmits heat generated by the light-emitting element 41 to the temperature control device 20. The carrier 43 may also be called a submount.

[0047] The light emitting element 41 outputs a laser beam toward the lens 42. The wavelength of the laser beam is, for example, 900 nm or more and 1650 nm or less, which is a suitable wavelength for optical communication. The temperature of the light emitting element 41 rises while the laser beam is being output, and the light emitting element 41 functions as a heating element. The light emitting element 41 is, for example, a semiconductor laser element.

[0048] The lens 42 is attached to a carrier 43. The lens 42 acts on the laser light from the light emitting element 41 by using a refractive index to collimate the laser light. The laser light output from the lens 42 is input to an optical isolator 51.

[0049] The optical isolator 51 has a magnet 51a and an optical element section 51b including a magneto-optical element and a polarizing plate. The optical isolator 51 polarizes the laser light from the optical element section 51b and exerts a magneto-optical effect on the laser light from the optical element section 51b. The laser light output from the optical isolator 51 is input to the beam splitter 52. The optical isolator 51 prevents the light from the beam splitter 52 from passing toward the light-emitting element 41.

[0050] The beam splitter 52 outputs the laser light from the optical isolator 51 to the outside of the optical device 1 , and also splits the laser light from the optical isolator 51 into light beams and inputs them to a light receiving element 53 .

[0051] The housing 10 is hermetically sealed, which prevents air and water from acting on optical components housed within the housing 10, such as the light-emitting element 41, lens 42, optical isolator 51, beam splitter 52, and light-receiving element 53. The optical device 1 is configured so that an inert gas, such as nitrogen gas, filled into the housing 10 during manufacturing does not leak out of the housing 10.

[0052] A flexible printed wiring board 30 is also connected to the optical device 1. In this embodiment, the flexible printed wiring board 30 is fixed to the feedthrough 16. The flexible printed wiring board 30 may be fixed to the feedthrough 16 or the housing 10 using a fastener (not shown) such as a screw or an adhesive.

[0053] Driving power and control signals are supplied from a host device (not shown) to the light emitting element 41 and the temperature adjustment device 20 via the conductors in the flexible printed wiring board 30. In addition, a detection signal is sent from a sensor (not shown) in the accommodation chamber R to the host device via the conductors in the flexible printed wiring board 30.

[0054] Figure 2 is an enlarged view of part II in Figure 1. Figure 2 shows a cross section of a welding structure 60A (60) formed on the housing 10, welding the top wall 11 and the side wall 13 together. Note that a welding structure 60A similar to that shown in Figure 2 is also provided between the top wall 11 and the side wall 14.

[0055] As shown in FIG. 2 , in this embodiment, the peripheral edge 11b of the top wall 11 and the edge 13b of the side wall 13 are joined via a weld 61. The weld 61 is formed by irradiating the laser beam L to form a molten pool, which is then cooled and solidified. That is, the top wall 11 and the side wall 13 are laser welded together. The top wall 11 is a member that forms a lid of the housing 10 and closes the openings of the side walls 13 and 14, and is an example of a first member. The side walls 13 and 14 are members that form the peripheral walls of the housing 10, and are an example of a second member. The peripheral edge 11b is an example of a first edge. The edge 13b is a linear edge that extends along the peripheral edge 11b, and is an example of a second edge.

[0056] Edge 13b, together with the edges of other side walls 13 and 14, forms a peripheral edge along peripheral edge 11b. Furthermore, welded structure 60 is not limited to being formed between side wall 13 and top wall 11, but may be formed, for example, at corner A between side wall 13 and bottom wall 12 shown in FIG. 1 or at a corner (not shown) between side wall 14 and bottom wall 12, or at a butt joint (not shown) between two members aligned in the extension direction.

[0057] As shown in Fig. 2, the welded portion 61 is located between the outer surface 11s of the top wall 11 and the outer surface 13s of the side wall 13. The outer surfaces 11s and 13s both extend across the Z direction, in other words, they extend in the X and Y directions. As an example, the outer surfaces 11s and 13s are substantially flush with each other, with a deviation in the Z direction set to 0.1 mm or less. The outer surface 11s is an example of a first outer surface, and the outer surface 13s is an example of a second outer surface.

[0058] In this embodiment, the boundary portion B between the peripheral edge 11b and the end edge 13b extends between the outer surface 11s and the outer surface 13s and between the storage chamber R. The boundary portion B has two sections B1 and B2. Section B1 is adjacent to the outer surfaces 11s and 13s. Sections B1 and B2 are arranged in series, with section B2 being located closer to the storage chamber R than section B1. As can be seen from FIG. 2, the boundary portion B is bent in an L-shape in the cross section of FIG. 2. That is, the extension direction of section B1 and the extension direction of section B2 intersect with each other. Section B1 extends in the Z direction from between the outer surface 11s and the outer surface 13s toward the storage chamber R, and section B2 extends in the opposite direction to the X direction from the end of section B1 on the storage chamber R side toward the storage chamber R.

[0059] Welded portion 61 joins peripheral edge 11b and edge 13b in section B1. In Fig. 2, boundary portion B of welded portion 61 before welded portion 61 is formed is shown by a two-dot chain line.

[0060] Here, Fig. 2 is a cross section intersecting with the Y direction. In other words, in the portion where the cross section of Fig. 2 is formed, peripheral edge 11b, edge 13b, outer surface 11s, outer surface 13s, boundary portion B, sections B1 and B2, and welded portion 61 extend in the Y direction intersecting with the plane of Fig. 2. That is, the Y direction is a direction along outer surfaces 11s and 13s and along peripheral edge 11b and edge 13b. The Y direction is an example of a first direction.

[0061] The laser light L is irradiated in the Z direction toward section B1 of boundary portion B. That is, the irradiation direction I of the laser light L is the Z direction. Therefore, the welded portion 61 extends in the irradiation direction I from between the outer surface 11s and the outer surface 13s in the portion where the cross section of FIG. 2 is formed. The irradiation direction I is an example of a second direction. The irradiation direction I may also be referred to as the depth direction of the welded portion 61.

[0062] In the welding process, laser light L irradiated from laser welding apparatus 100 (see FIG. 7) is swept in the Y direction while irradiated at least in the region where the cross section of FIG. 2 is formed, causing welded portion 61 to extend in the Y direction. In this embodiment, peripheral edge 11b, end edge 13b, and the end edge of side wall 14 have the same configuration as in FIG. 2 over their entire periphery. That is, peripheral edge 11b, end edge 13b, and the end edge of side wall 14 are seam-welded via welded portion 61 over the entire periphery of the edge of top wall 11, which serves as a lid for the opening of side wall 13, and storage chamber R is hermetically sealed at welded portion 61.

[0063] In section B1 of boundary portion B, end face 11c and end face 13c face in the X direction. End face 11c faces the X direction and extends in a direction intersecting the X direction. In other words, end face 11c extends in the Y direction and the Z direction. On the other hand, end face 13c faces the opposite direction to the X direction and extends in a direction intersecting the X direction. In other words, end face 13c extends in the Y direction and the Z direction. End face 11c and end face 13c are in contact with each other or face each other with a gap therebetween. Section B1 extends in the Y direction and in the Z direction toward storage chamber R. Section B1 is an example of an opposing section and a first opposing section. In addition, in section B1, the Z direction is an example of a second direction.

[0064] In section B2, end face 11d and end face 13d face the Z direction. End face 11d faces the Z direction and extends in a direction intersecting the Z direction. In other words, end face 11d extends in the X direction and the Y direction. On the other hand, end face 13d faces the opposite direction to the Z direction and extends in a direction intersecting the Z direction. In other words, end face 13d extends in the X direction and the Y direction. End face 11d and end face 13d are in contact with each other or face each other with a gap therebetween. Section B2 extends in the Y direction and also extends in the opposite direction to the X direction toward storage chamber R. Section B2 is an example of an opposing section and a second opposing section. In addition, the direction opposite to the X direction in section B2 is an example of a third direction.

[0065] The section B2 extends substantially along the X direction, which is the thickness direction of the side wall 13, and the length T31 ​​of the section B2 in the X direction is half or more of the thickness T3 of the side wall 13.

[0066] As described above, in this embodiment, the weld 61 that welds the top wall 11 (first member) and the side wall 13 (second member) together extends in the Z direction (irradiation direction I, second direction) between the outer surface 11s (first outer surface) and the outer surface 13s (second outer surface). Furthermore, the boundary portion B includes a section B1 and a section B2, with the section B1 (opposing section, first opposing section) extending in the Z direction (second direction) and the section B2 (opposing section, second opposing section) extending in the direction opposite the X direction (third direction).

[0067] In this configuration, the laser beam L is irradiated toward the section B1 substantially along the Z direction in which the section B1 extends. Therefore, compared to when the welded portion is formed so as to penetrate the top wall 11 or the side wall 13, the energy of the laser beam L is more easily transmitted along the section B1, and thus the welded portion 61 can be formed with less energy. This reduces the occurrence of spatter. Furthermore, the section B2, which is located closer to the accommodating chamber R than the section B1 where the welded portion 61 is formed, extends in the opposite direction to the X direction, which intersects with the Z direction, which is the extension direction of the section B1. That is, before the welded portion 61 is formed, the boundary portion B is bent between the outer surface 11s and the outer surface 13s and the accommodating chamber R. Therefore, even if spatter occurs in the section B1 during the process of forming the welded portion 61, the boundary portion B bends toward the accommodating chamber R, making it more difficult for the spatter to enter the accommodating chamber R along the boundary portion B than if the boundary portion extended linearly. Therefore, this configuration can prevent spatters from affecting the optical components in the accommodation chamber R. When the sections B1 and B2 intersect at the boundary portion B, the extension direction (Z direction) of the welded portion 61 and the extension direction (opposite to the X direction) of the section B2 intersect.

[0068] Furthermore, as in this embodiment, in at least a portion of sections B1 and B2 (opposing sections), for example section B2, end face 11d, i.e., peripheral edge 11b (first edge), and end face 13d, i.e., edge 13b (second edge), may be in contact with each other.

[0069] With this configuration, for example, a portion where the peripheral edge 11b and the end edge 13b contact each other can be formed at the boundary portion B, making it more difficult for spatter to enter the housing chamber R along the boundary portion B compared to a configuration where the peripheral edge 11b and the end edge 13b do not contact each other. Therefore, with this configuration, it is possible to further prevent spatter from affecting the optical components in the housing chamber R. In this case, the end faces 11d, 13d, which are the contacting portions, may serve as positioning portions for the top wall 11 and the side wall 13 in the Z direction. With this configuration, the configuration of the housing 10 can be further simplified compared to a case where the positioning portions are provided separately from the boundary portion B.

[0070] Furthermore, when section B2 extends in the thickness direction (X direction) of side wall 13 as in this embodiment, the length T31 ​​of section B2 in the thickness direction may be half or more of the thickness T3 of side wall 13.

[0071] In this case, the length of section B2 can be made longer than when the length of section B2 is less than half the thickness T3, making it even more difficult for sputters to enter the accommodation chamber R along the boundary portion B. Therefore, it is possible to further prevent sputters from affecting the optical components inside the accommodation chamber R.

[0072] [First Modification] Fig. 3 is a cross-sectional view of a welded structure 60B (60) of a first modified example of the first embodiment, taken at the same position as in Fig. 2. This modified example differs from the above embodiment in that the boundary portion B includes an intermediate chamber S. Except for the presence or absence of the intermediate chamber S, the welded structure 60B has the same configuration as the welded structure 60A of the embodiment.

[0073] The intermediate chamber S is a portion of the boundary portion B where the gap size h (height) between the peripheral edge 11b and the end edge 13b is larger than that of other portions. The intermediate chamber S is provided between the welded portion 61 or section B1 and the storage chamber R, and extends in the Y direction. In a cross section intersecting with the Y direction, the maximum value of the gap size h is preferably 0.2 mm or more. Note that the position of the intermediate chamber S is not limited to that shown in FIG. 3, as long as it is located between the welded portion 61 and the storage chamber R.

[0074] According to this configuration, even if spatter occurs in section B1 during the process of forming welded portion 61, the spatter can be captured or contained in intermediate chamber S, making it difficult for the spatter to enter storage chamber R along boundary portion B. Therefore, according to this modified example, the spatter can be further prevented from affecting the optical components in storage chamber R.

[0075] [Second Modification] Fig. 4 is a cross-sectional view of a welded structure 60C(60) according to a second modified example of the first embodiment, taken at the same position as in Fig. 2. This modified example differs from the above embodiment and the first modified example in that a boundary portion B is provided between outer surfaces 11s and 13s, which face the X direction and are aligned substantially flush in the Z direction, and extends to the accommodation chamber R, and that boundary portion B is bent in a Z shape.

[0076] In this modification, the boundary portion B has three sections B1, B21, and B22. Section B1 is adjacent to the outer surfaces 11s and 13s. Section B21 is located closer to the storage chamber R than section B1, and section B22 is located closer to the storage chamber R than section B21.

[0077] In section B1 of boundary portion B, end face 11e and end face 13e face in the Z direction. End face 11e faces the Z direction and extends in a direction intersecting the Z direction. In other words, end face 11e extends in the X direction and the Y direction. On the other hand, end face 13e faces the opposite direction to the Z direction and extends in a direction intersecting the Z direction. In other words, end face 13e extends in the X direction and the Y direction. End face 11e and end face 13e are in contact with each other or face each other with a gap therebetween. Section B1 extends in the Y direction and also extends in the opposite direction to the X direction toward storage chamber R. Section B1 is an example of an opposing section and a first opposing section. Furthermore, in section B1, the direction opposite to the X direction is an example of a second direction.

[0078] In section B21, end face 11c and end face 13c face in the X direction. End face 11c faces the X direction and extends in a direction intersecting the X direction. In other words, end face 11c extends in the Y direction and the Z direction. On the other hand, end face 13c faces the opposite direction to the X direction and extends in a direction intersecting the X direction. In other words, end face 13c extends in the Y direction and the Z direction. End face 11c and end face 13c are in contact with each other or face each other with a gap therebetween. Section B21 extends in the Y direction and in the Z direction toward storage chamber R. Section B21 is an example of an opposing section and a second opposing section. In section B21, the Z direction is an example of a third direction.

[0079] In this modification, section B21 extends substantially along the Z direction, which is the thickness direction of top wall 11, and length T11 of section B21 in the Z direction is half or more of thickness T1 of top wall 11.

[0080] In section B22 of boundary portion B, end face 11d and end face 13d face in the Z direction. End face 11d faces the Z direction and extends in a direction intersecting the Z direction. In other words, end face 11d extends in the X direction and the Y direction. On the other hand, end face 13d faces the opposite direction to the Z direction and extends in a direction intersecting the Z direction. In other words, end face 13d extends in the X direction and the Y direction. End face 11d and end face 13d are in contact with each other or face each other with a gap therebetween. Section B22 extends in the Y direction and also extends in the opposite direction to the X direction toward storage chamber R. Section B22 is an example of an opposing section and a second opposing section. Furthermore, in section B22, the direction opposite to the X direction is an example of a third direction.

[0081] According to the present modified example, the boundary portion B includes a plurality of sections B21, B22 (opposing sections). The sections B21, B22 are arranged in series between the welded portion 61 and the accommodation chamber R and extend in different directions. With this configuration, it is even more difficult for spatter to enter the accommodation chamber R along the boundary portion B than when there is only one opposing section. Therefore, according to the present modified example, it is possible to further suppress the influence of spatter on the optical components in the accommodation chamber R.

[0082] [Third Modification] FIG. 5 is a cross-sectional view of a welded structure 60D (60) according to a third modified example of the first embodiment, taken at the same position as in FIG. 2. The welded structure 60D according to this modified example has an intermediate chamber S similar to that of the first modified example. The intermediate chamber S is provided between the welded portion 61 or section B1 and the storage chamber R, and extends in the Y direction. Note that the position of the intermediate chamber S need only be between the welded portion 61 and the storage chamber R, and is not limited to the position shown in FIG. 5. The welded structure 60D has the same configuration as the welded structure 60C according to the second modified example, except for the presence or absence of the intermediate chamber S. Therefore, according to this modified example, the same effects as those of the second modified example can be obtained, and the same effects as those of the first modified example due to the provision of the intermediate chamber S can also be obtained.

[0083] [Fourth Modification] 6 is a cross-sectional view of a welded structure 60E (60) according to a fourth modified example of the first embodiment, taken at the same position as in FIG. 2. In this modified example, as in the second and third modified examples, a boundary portion B is provided from the outer surface 11s and the outer surface 13s, which face the X direction and are aligned substantially flush in the Z direction, to the storage chamber R, and the boundary portion B is bent in a Z-shape. However, in this modified example, a section B21 extends from the section B1 in the opposite direction in the Z direction toward the storage chamber R, and a section B22 extends from the end of the section B21 on the opposite side in the Z direction toward the storage chamber R in the opposite direction in the X direction. This modified example provides the same effects as the second modified example, which has a boundary portion B bent in a Z-shape.

[0084] In this modification, the end surface 11d is provided as the bottom surface of a recess 11g provided in the top wall 11. The recess 11g extends in the Y direction and may also be referred to as a recessed groove. In this case, the side surface of the recess 11g on the opposite side in the X direction becomes a wall facing the section B22 of the boundary portion B with a gap therebetween. This further prevents spatter from entering the accommodation chamber R, and thus further prevents spatter from affecting the optical components in the accommodation chamber R. However, the groove-shaped recess 11g is not essential and may be provided as needed.

[0085] [Second embodiment] [Laser welding equipment] Fig. 7 is a diagram showing a schematic configuration of a laser welding apparatus 100 of the second embodiment. As shown in Fig. 7, the laser welding apparatus 100 includes a laser device 110, an optical head 120, and an optical fiber 130. The laser welding apparatus 100 can provide the welding structure 60 of the first embodiment and each of the modified examples.

[0086] The laser welding apparatus 100 irradiates a laser beam L onto a surface Wa of a housing 10, which is an object W to be laser welded. The energy of the laser beam L causes the object W to partially melt, and then the object W is cooled and solidified, thereby welding the object W and forming a welded structure 60. The object W has a plurality of members such as the top wall 11 and side wall 13 of the first embodiment described above, and these plurality of members are joined by laser welding. In the first embodiment and its first to fourth modifications, the outer surfaces 11s and 13s are examples of the surface Wa.

[0087] The laser device 110 has a laser oscillator and is configured to output, for example, a single-mode laser beam with a power of several kW. The laser device 110 may also have, for example, a plurality of semiconductor laser elements therein, configured to output a multi-mode laser beam with a power of several kW as the total output of the plurality of semiconductor laser elements. The laser device 110 may also have various laser light sources, such as a fiber laser, a YAG laser, or a disk laser. The laser device 110 outputs, for example, a laser beam with a wavelength of 400 nm or more and 1200 nm or less.

[0088] The optical fiber 130 optically connects the laser device 110 and the optical head 120. In other words, the optical fiber 130 guides the laser light output from the laser device 110 to the optical head 120. When the laser device 110 outputs a single-mode laser light, the optical fiber 130 is configured to propagate the single-mode laser light. In this case, the M of the single-mode laser light 2 The beam quality is set to 1.3 or less. 2 The beam quality may also be referred to as the M2 factor.

[0089] The optical head 120 is an optical device that emits the laser light input from the laser device 110, in other words, irradiates the target object W. The optical head 120 has a collimator lens 121, a condenser lens 122, and a DOE 125 (diffractive optical element).

[0090] The collimating lenses 121 collimate the laser light input via the optical fibers 130. The collimated laser light becomes parallel light.

[0091] A DOE 125 is provided between the collimator lens 121 and the condenser lens 122. The DOE 125 will be described later.

[0092] The condenser lens 122 condenses the laser light coming from the DOE 125 as parallel light, and irradiates the object W with the laser light L (output light).

[0093] A drive mechanism (not shown) changes the relative positions of the object W and the optical head 120 by moving at least one of the object W and the optical head 120. The drive mechanism includes, for example, a rotation mechanism such as a motor, a speed reduction mechanism that reduces the rotation output of the rotation mechanism, and a motion conversion mechanism that converts the rotation reduced by the speed reduction mechanism into linear motion. The drive mechanism can translate the object W and the optical head 120 relatively in three mutually orthogonal directions, and rotate them relatively around the rotation axis Ax.

[0094] A controller (not shown) can control the drive mechanism to change the relative position of the optical head 120 in each direction with respect to the object W. The drive mechanism can also change (switch) the object W to be laser welded from among multiple objects W supported by a support mechanism (not shown). The drive mechanism can also change the irradiation position of the laser light L on the object W. The drive mechanism can also be used to change the irradiation point in conjunction with changing the irradiation direction I of the laser light with respect to the object W. The drive mechanism can also change the irradiation position while the laser light L is being irradiated onto the surface of the object W. In other words, the drive mechanism can sweep the laser light L over the surface of the object W. This allows seam welding of the welded portion 61 to be achieved.

[0095] The optical head 120 may also include a galvanometer scanner (not shown) having a plurality of mirrors. In this case, the controller may control the galvanometer scanner so that the laser light L is swept over the surface of the object W.

[0096] As described above, the optical head 120 also includes a DOE 125. The DOE 125 shapes the shape of a laser beam (hereinafter referred to as the beam shape). FIG. 8 is an explanatory diagram showing the concept of the principle of the DOE 125. As conceptually illustrated in FIG. 8, the DOE 125 has a configuration in which, for example, a plurality of diffraction gratings 125a with different periods are superimposed. The DOE 125 can shape the beam shape by bending the parallel light in a direction influenced by each diffraction grating 125a or by superimposing the diffraction gratings 125a. The DOE 125 may also be called a beam shaper.

[0097] [Beam (spot) shape] The DOE 125 splits the collimated laser light into multiple beams. FIGS. 9 to 11 are diagrams each showing an example of a beam of laser light L formed on the surface Wa of the object W. For simplicity, in FIGS. 9 to 11, beam Lb1 is shown by a solid line and beam Lb2 is shown by a dashed line. By replacing the DOE 125, the optical head 120 can output laser light including multiple beams in various arrangements. The DOE 125 is an example of a beam shaper.

[0098] The DOE 125 splits the laser light into multiple beams. The split beams include at least one beam Lb1 and at least one beam Lb2. The beam Lb2 has a lower power density than the beam Lb1. The beam Lb1 is an example of a main beam, and the beam Lb2 is an example of a sub-beam. The beam Lb1 forms a main power region, and the beam Lb2 forms a sub-power region.

[0099] In the example of Figure 9, a spot of one beam Lb1 and a spot of a beam Lb2 that is wider than the beam Lb1 are formed on the surface Wa. The beam Lb1 and the outer edge Lb1a of the beam Lb1 are located inside the outer edge Lb2a of the beam Lb2. Note that the beams Lb1 and Lb2 may be arranged concentrically or eccentrically. Furthermore, the outer edge Lb1a may be inscribed in the outer edge Lb2a or may be partially located outside the outer edge Lb2a.

[0100] 10, a spot of one beam Lb1 and spots of multiple beams b2 surrounding the beam Lb1 are formed on the surface Wa. The beam b2 is arranged in a substantially circular ring shape. The beam b2 is an example of a sub-beam, and a sub-power region is formed by the multiple beams b2.

[0101] 11, a spot of one beam Lb1 and spots of multiple beams b2 surrounding the beam Lb1 are formed on the surface Wa. However, the beams b2 are arranged in a substantially rectangular shape, that is, along the sides of an imaginary rectangle. The beam b2 is an example of a sub-beam, and the multiple beams b2 form a sub-power region.

[0102] In each of the laser beams L shown in Figures 9 to 11, at least a portion of the beam b2 (secondary power region) is positioned around the beam Lb1 (main power region). The laser beam L is shaped so that at least a portion of the beam Lb2 is positioned forward of the beam Lb1 in the sweep direction. Research by the inventors has revealed that sweeping while irradiating such laser beam L can suppress the occurrence of spatters and blowholes compared to sweeping while irradiating a laser beam having a single beam. This is thought to be because the surface Wa is preheated by at least a portion of the beam Lb2 before the formation of the molten pool, which stabilizes the molten pool in a fluid state compared to when the surface Wa is rapidly heated without preheating by a single beam. Therefore, the welding structure 60 (60A to 60E) disclosed in the first embodiment and its modified examples preferably has a structure including the bent boundary portion B as described above and a linear weld 61 formed by sweeping while irradiating the laser beam L including the beams Lb1 and Lb2.

[0103] While the above describes exemplary embodiments and modifications of the present invention, these are merely examples and are not intended to limit the scope of the invention. The above embodiments and modifications can be implemented in various other forms, and various omissions, substitutions, combinations, and modifications can be made without departing from the spirit of the invention. Furthermore, the specifications of each configuration, shape, and the like (structure, type, direction, model, size, length, width, thickness, height, number, arrangement, position, material, etc.) can be modified as appropriate.

[0104] For example, the optical device may include, as optical components, a semiconductor laser element, a light receiving element, a semiconductor modulator, a semiconductor optical amplifier, etc. The optical device may include, as optical components, at least one of the semiconductor laser element, the light receiving element, the semiconductor modulator, and the semiconductor optical amplifier. [Explanation of symbols]

[0105] 1...Optical device 10. Housing 11...Top wall (first member) 11b...periphery (first edge) 11c...end face 11d...end face 11e...End face 11g...recess 11s...Outer surface (first outer surface) 12...Bottom wall 13...Side wall (second member) 13b...Edge (second edge) 13c...end face 13d...end face 13e...End face 13s...Outer surface (first outer surface) 14...Side wall (second member) 15...Optical window 16...Feedthrough 20…Temperature control device 20a…Top surface 20b…Bottom surface 21U: Upper board 21L…Lower board 21a…Top surface 21b…Bottom surface 22...Thermoelectric element 30...Flexible printed wiring board 41...Light emitting element 42...Lens 43...Career 51...Optical isolator 51a...Magnet 51b...optical element section 52...Beam splitter 53...Photodetector 60, 60A to 60E...welded structure 61...Welded section 100...Laser welding device 110...Laser device 120...Optical head 121...Collimating lens 122...Condenser lens 125…DOE 125a...diffraction grating 130...Optical fiber A...Corner Ax...rotation axis B...boundary part B1...Section (opposing section, first opposing section) B2, B21, B22... Sections (opposing section, second opposing section) b2...beam I…Irradiation direction (second direction) L...laser light Lb1...Beam (main beam) Lb1a…outer edge Lb2...Beam (secondary beam) Lb2a…outer edge R…Containment room S…Intermediate room T1, T3...Thickness T11, T31...length W...Object Wa...surface X...direction (opposite direction of the third direction, opposite direction of the second direction) Y…direction (first direction) Z…direction (second direction, third direction)

Claims

1. A housing for an optical device that forms a chamber for accommodating optical components, a plate-shaped first member having a first outer surface that becomes the outer surface of the housing and a first edge; a plate-shaped second member having a second outer surface that becomes the outer surface of the housing and a second edge that extends along the first edge; a linear weld portion that welds the first edge and the second edge at a boundary portion between the first edge and the second edge and extends in a second direction that intersects with a first direction along the first edge; Equipped with the boundary portion includes an opposing section between the welded portion and the storage chamber where the first end edge and the second end edge face each other with a gap therebetween or are in contact with each other, and an intermediate chamber where the size of the gap between the first end edge and the second end edge at the boundary portion is larger than that of other portions, the intermediate chamber is spaced from the accommodation chamber at a position between the welded portion and the accommodation chamber, and is provided such that a part of the facing section is interposed between the intermediate chamber and the welded portion, The housing of the optical device, wherein the opposing sections include opposing sections extending in a third direction intersecting the first direction and the second direction.

2. The housing for an optical device according to claim 1 , wherein the maximum value of the size of the gap in a cross section intersecting with the first direction is 0.2 mm or more.

3. The housing for an optical device according to claim 1 or 2, wherein the boundary portion includes, as the opposing sections, a plurality of opposing sections arranged in series between the welded portion and the storage chamber and extending in different directions from each other.

4. 4. The housing for an optical device according to claim 1, wherein the first edge and the second edge are in contact with each other in at least a part of the opposing section.

5. A housing for an optical device described in any one of claims 1 to 4, wherein the boundary portion includes an opposing section extending approximately along the thickness direction of one of the first and second members for a length equal to or greater than half the thickness of the one member.

6. 6. The housing for an optical device according to claim 1, wherein the deviation between the first outer surface and the second outer surface in the second direction is 0.1 mm or less.

7. 7. The housing for an optical device according to claim 1, wherein the welded portion is provided circumferentially.

8. 8. The housing for an optical device according to claim 1, wherein the chamber is hermetically sealed at the welded portion.

9. the first member is a member constituting a lid of the housing that closes an opening in a peripheral wall of the housing, the second member is a member that constitutes the peripheral wall, the first edge is a peripheral edge of the lid; 9. The housing for an optical device according to claim 1, wherein the second edge is a peripheral edge of the peripheral wall extending along the first edge.

10. a housing for an optical device according to any one of claims 1 to 9; an optical component accommodated in the accommodation chamber; An optical device comprising:

11. A housing for an optical device that forms a chamber for accommodating optical components, a plate-shaped first member having a first outer surface that becomes the outer surface of the housing and a first edge; a plate-shaped second member having a second outer surface that becomes the outer surface of the housing and a second edge that extends along the first edge; a linear weld portion that welds the first edge and the second edge at a boundary portion between the first edge and the second edge and extends in a second direction that intersects with a first direction along the first edge; Equipped with the boundary portion includes an opposing section between the welded portion and the storage chamber where the first end edge and the second end edge face each other with a gap therebetween or are in contact with each other, and an intermediate chamber where the size of the gap between the first end edge and the second end edge at the boundary portion is larger than that of other portions, the intermediate chamber is spaced from the accommodation chamber at a position between the welded portion and the accommodation chamber, and is provided such that a part of the facing section is interposed between the intermediate chamber and the welded portion, a laser welding apparatus for forming the welded portion of the housing, the opposing sections including opposing sections extending in a third direction intersecting the first direction and the second direction, a laser oscillator; an optical head that emits laser light from the laser oscillator; Equipped with The laser welding device forms the welded portion by sweeping the laser light from the optical head toward the housing while irradiating it.

12. The laser welding device according to claim 11, further comprising a beam shaper that shapes the laser beam.

13. A housing for an optical device that forms a chamber for accommodating optical components, a plate-shaped first member having a first outer surface that becomes the outer surface of the housing and a first edge; a plate-shaped second member having a second outer surface that becomes the outer surface of the housing and a second edge that extends along the first edge; a linear weld portion that welds the first edge and the second edge at a boundary portion between the first edge and the second edge and extends in a second direction that intersects with a first direction along the first edge; Equipped with the boundary portion includes an opposing section between the welded portion and the storage chamber where the first end edge and the second end edge face each other with a gap therebetween or are in contact with each other, and an intermediate chamber where the size of the gap between the first end edge and the second end edge at the boundary portion is larger than that of other portions, the intermediate chamber is spaced from the accommodation chamber at a position between the welded portion and the accommodation chamber, and is provided such that a part of the facing section is interposed between the intermediate chamber and the welded portion, The facing sections include facing sections extending in a third direction intersecting the first direction and the second direction, A laser welding method in which the laser beam is irradiated and swept toward the housing.

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