JP7132747B2 - optical subassembly - Google Patents

Description

The present invention relates to optical subassemblies.

2. Description of the Related Art In an optical communication system, an optical module is used that contains an optical subassembly (OSA) and converts an optical signal and an electrical signal from one to the other, or bidirectionally. The OSA is a semiconductor optical device that converts the above-mentioned optical signal and electrical signal, specifically, a light emitting device such as a laser diode (LD) and a light receiving device such as a photodiode (PD) in a housing. It is a stored part.

In order to cope with the miniaturization and high functionality of optical modules, there is known an OSA that accommodates a plurality of semiconductor optical devices in one housing and supports multiplexing of signals of a plurality of channels (Patent Document 1 below). .

Also, an optical module is known that includes a structure in which four light emitting elements of a CAN package are arranged like four dice for miniaturization (Patent Document 2 below).

JP 2016-178218 A JP 2013-232514 A

In order to further speed up data transmission, there is a demand for an OSA that performs wavelength division multiplexing (WDM) of 4 or more channels, for example, 8 channels. Here, as shown in OSA of Patent Document 1, by arranging a plurality of light emitting elements in a line in a direction orthogonal to their optical axes, it is possible to prevent the light emitting elements from obstructing the optical path. can. However, in this configuration, as the number of channels increases, the arrangement width of the semiconductor optical elements also increases. In addition, as disclosed in Patent Document 2, a configuration in which a plurality of semiconductor optical devices housed in a CAN-type package are arranged side by side also has a problem that miniaturization of the optical module is restricted by the size of the package.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and provides an OSA that is compact and accommodates a larger number of semiconductor optical devices, and that increases the number of WDM channels to increase the speed of data transmission and optical modules. downsizing.

(1) An optical subassembly according to the present invention accommodates a plurality of semiconductor optical devices arranged with their optical axes parallel, a submount having the semiconductor optical devices mounted on both main surfaces thereof, and the submount. and a housing, wherein the housing is two protrusions or steps separated in a width direction intersecting the optical axis and provided on a side surface or a bottom surface inside the housing, wherein the sub A sub-mount support base is provided that abuts on the edge portions of the widthwise both ends of one of the main surfaces of the mount.

(2) In the optical subassembly described in (1) above, the housing is provided upright between the two submount supports, and is in contact with the one main surface of the submount. It can be a configuration comprising a strut that is

(3) In the optical subassembly described in (1) and (2) above, a plurality of the semiconductor optical devices are arranged in the width direction on the one main surface of the submount, and the plurality of semiconductor optical devices are arranged in the width direction. A wiring group having one end connected to the semiconductor optical device is arranged in parallel in the width direction, and an arrangement region of the wiring group on the main surface is located on the one end side of the wiring group and the semiconductor optical device. and a narrowed portion located on the other end side of the wiring group and narrower in width than the widened portion, and the submount support supports the light beam along with the edge portion. It may be characterized in that it extends in the axial direction and has a larger dimension in the width direction at the portion facing the constricted portion than at the portion facing the wide portion.

(4) In the optical subassembly described in (1) to (3) above, the semiconductor has a lens for condensing the output light of the semiconductor optical element and is mounted on the one main surface of the submount. The lens for the optical element may be installed on the bottom surface, and the lens for the semiconductor optical element mounted on the other main surface may be supported by the submount support base.

According to the present invention, it is possible to obtain an OSA that is small and accommodates a larger number of semiconductor optical devices.

1 is a perspective view showing the appearance of an optical module according to an embodiment of the invention; FIG. 1 is a schematic top view showing the configuration of an optical transmission device equipped with an optical module according to an embodiment of the present invention; FIG. FIG. 4 is a schematic side view showing the optical subassembly, printed circuit board and flexible substrate; 1 is a schematic top view of an OSA according to a first embodiment of the invention; FIG. 5 is a schematic vertical cross-sectional view of the OSA along line VV of FIG. 4; FIG. FIG. 4 is a schematic plan view of the lower surface side of the submount; FIG. 2 is a schematic top view of the exterior case of the OSA according to the first embodiment of the present invention; FIG. 4 is a schematic vertical sectional view of an OSA according to a second embodiment of the invention; FIG. 5 is a schematic top view of an exterior case of an OSA according to a second embodiment of the present invention; FIG. 11 is a schematic top view of an exterior case of an OSA according to a third embodiment of the present invention; FIG. 4 is a schematic top view of an OSA having features of the second and third embodiments of the present invention;

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments (hereinafter referred to as embodiments) of the present invention will be described below with reference to the drawings. In addition, in all the drawings for describing the embodiments, members having the same functions are denoted by the same reference numerals, and repeated description thereof will be omitted.

[First Embodiment]
FIG. 1 is a perspective view showing the appearance of an optical module 10 according to an embodiment of the invention. The optical module 10 is an optical transmitter/receiver (optical transceiver) having a transmission function and a reception function. The outer shape of the optical module 10 is composed of parts including a case 12 , a pull tab 14 and a slider 16 .

FIG. 2 is a schematic top view showing the configuration of the optical transmission device 18 to which the optical module 10 is attached. A plurality of optical modules 10 are attached to an optical transmission device 18 by electrical connectors 20, respectively. The optical transmission device 18 is, for example, a large-capacity router or switch. The optical transmission device 18 has, for example, a switching function, and is arranged in a base station or the like. The optical transmission device 18 acquires data for reception (electrical signal for reception) from the optical module 10 and uses a driver IC (integrated circuit) 24 mounted on a circuit board 22 to transmit what data to where. It determines whether to transmit, generates data for transmission (electrical signal for transmission), and transmits the data to the corresponding optical module 10 .

The optical module 10 comprises a printed circuit board 26, a flexible board 28, and an optical subassembly (OSA) 30 for converting at least one of optical and electrical signals to the other. An optical fiber 32 is connected to the OSA 30 for input/output of optical signals.

Specifically, the OSA 30 includes a transmitter optical subassembly (TOSA) having an optical transmission function, a receiver optical subassembly (ROSA) having an optical reception function, and a bidirectional subassembly having an optical transmission/reception function. (Bi-directional Optical SubAssembly: BOSA). For example, the optical module 10 has two OSAs 30-1 and 30-2.

FIG. 3 is a schematic side view of OSA 30, printed circuit board 26, and flexible circuit board 28. FIG. The printed circuit board 26 is a rigid circuit board, while the flexible circuit board 28 is flexible and connected to the printed circuit board 26 and the OSA 30 at both ends. That is, one end of the wiring formed on the flexible substrate 28 overlaps with the terminal board 34 of the OSA 30 and is electrically connected, and the other end of the wiring overlaps with the terminal of the printed circuit board 26 and is electrically connected. An electrical signal is transmitted between the printed circuit board 26 and the OSA 30 by . For example, OSA 30-1 is a TOSA, and electrical signals from printed circuit board 26 are transmitted to OSA 30-1 through flexible substrate 28, while OSA 30-2 is a ROSA, and electrical signals are transmitted from OSA 30-2 to flexible substrate 28. is transmitted to the printed circuit board 26 via the .

FIG. 4 is a schematic top view of an example of the OSA 30 according to the first embodiment of the invention. The OSA 30 accommodates a submount 44 on which a semiconductor optical device 42 is mounted, and the like in an exterior case 40 that is a housing. Here, as shown in FIGS. 1 and 2, the optical module 10 has an electrical connector 20 at one longitudinal end of the elongated case 12, and an optical fiber 32 is connected to the other longitudinal end. Correspondingly, a relatively small upper limit is imposed on the dimension (lateral width) of the OSA 30 in the lateral direction of the case 12, and the external case 40 is basically elongated and has the same longitudinal direction as the case 12. . A terminal board 34 connected to the flexible board 28 is provided at one end of the exterior case 40 in the longitudinal direction, and an optical fiber connector 48 is provided at the other end.

Here, for convenience of explanation, an XYZ orthogonal coordinate system for the OSA 30 is defined in a right-handed system with the longitudinal direction of the exterior case 40 as the X axis, the width direction as the Y axis, and the height direction as the Z axis. The direction from the terminal board 34 to the optical fiber connector 48 is set to the positive direction of the X-axis. The XY plane is the horizontal plane, and the Z axis is the vertical direction. The submount 44 is stored in the exterior case 40 with the substrate surface horizontal.

The OSA 30 is used for WDM optical transmission, and incorporates a plurality of semiconductor optical devices. For example, in this embodiment, the bit rate of the signal transmitted and received by the optical module 10 is 400 Gbit/s, and the signal is transmitted as an eight-wavelength multiplexed optical signal. That is, the optical module 10 transmits and receives 8-channel signals of 50 Gbit/s. Correspondingly, the OSA 30 incorporates eight semiconductor optical devices 42 . A plurality of semiconductor optical devices 42 are arranged on a submount 44 with their optical axes parallel. In this embodiment, the optical axis of each semiconductor optical device 42 is set parallel to the X-axis.

Incidentally, the semiconductor optical device 42 is an optical conversion device that converts one of an optical signal and an electrical signal into the other. Specifically, the OSA 30-1, which is a TOSA, has a light-emitting element such as a laser diode as an optical conversion element for converting an electrical signal into an optical signal for each of the eight channels. Each has a light receiving element such as a photodiode as an optical conversion element that converts an optical signal into an electrical signal.

4 exemplifies an OSA 30-1 which is a TOSA, and in addition to the submount 44, the condensing lens 50 and the optical multiplexer 52 are accommodated in the outer case 40. As shown in FIG. The condenser lens 50 is arranged on the optical axis of the optical signal output from each of the eight light emitting elements, converts the optical signal into collimated light, and inputs the collimated light to the optical multiplexer 52 . The optical multiplexer 52 multiplexes the optical signals output from each of the eight light emitting elements to generate one optical signal to be transmitted through the optical fiber 32 . The optical multiplexer 52 is configured by well-known technology using, for example, prisms, mirrors, and the like.

Regarding the arrangement of the plurality of semiconductor optical devices 42 , it is required that each semiconductor optical device 42 does not become an obstacle to optical signals emitted from other semiconductor optical devices 42 or incident on the semiconductor optical devices 42 . For that purpose, for example, a plurality of semiconductor optical devices 42 may be arranged in a direction intersecting the optical axis. In this embodiment, a plurality of semiconductor optical devices 42 are separately mounted on both main surfaces (upper surface and lower surface) of a substrate forming a submount 44, and the plurality of semiconductor optical devices 42 mounted on each main surface are mounted on the Y-axis. arranged in a row in the direction By arranging the semiconductor optical devices 42 separately on both sides of the submount 44 in this way, the width of the OSA 30 can be made smaller than when all the semiconductor optical devices 42 are arranged on one side of the submount 44. As a result, the lateral width of the optical module 10 can be reduced.

In particular, the difference between the number of semiconductor optical devices 42 arranged on one principal surface of the submount 44 and the number of semiconductor optical devices 42 arranged on the other principal surface is reduced. By equalizing the numbers, the width of the OSA 30 can be suitably reduced. Therefore, in the present embodiment, the same number is arranged on both sides of the submount 44 .

FIG. 5 is a schematic vertical cross-sectional view of OSA 30 along line VV of FIG. The eight semiconductor optical devices 42 are arranged separately on the upper surface and the lower surface of the submount 44 as described above. Optical elements 42-5 to 42-8 are arranged in the Y-axis direction.

A plan view of the top side of the submount 44 is shown in FIG. 4, and FIG. 6 shows a plan view of the bottom side of the submount 44. As shown in FIG. In this embodiment, the layout on the main surface of the submount 44 is basically common between the upper surface side and the lower surface side. Specifically, the semiconductor optical device 42 is arranged on the rectangular side of the submount 44 nearer to the condenser lens 50 side. It extends in the X direction between the sides on the substrate 34 side.

The wiring 56 on the submount 44 and the wiring 58 on the terminal board 34 are electrically connected via a feedthrough (not shown) penetrating the side wall of the exterior case 40 . Although wiring 58 connected to the semiconductor optical device 42 arranged on the upper surface side of the submount 44 is shown on the upper surface of the terminal substrate 34 shown in FIG. The wiring 58 to be connected can be arranged on the lower surface of the terminal substrate 34 . In this case, the wiring 58 on the lower surface side is led out to the upper surface side of the terminal substrate 34 via vias and electrically connected to the wiring of the flexible substrate 28 connected to the upper surface of the terminal substrate 34 as shown in FIG. . Alternatively, vias may be provided in the submount 44 and the wiring of the semiconductor optical device 42 on the lower surface side of the submount 44 may be led out to the upper surface side. All of them can be arranged on the upper surface of the terminal substrate 34 .

As shown in FIG. 5, the submount 44 is supported at a predetermined position in the Z-axis direction by a submount support base 54 provided inside the exterior case 40 . The submount support base 54 is two protrusions or steps separated in the Y-axis direction and provided on the inner side surface or bottom surface of the exterior case 40 . The submounts 44 are supported by being brought into contact with the edges at both ends in the axial direction. In the example shown in FIG. 5, the submount support base 54 is a step provided on the inner side surface of the exterior case 40, and the portion below the step among the side surfaces of the exterior case 40 is positioned inside the portion above the step. Then, the lower surface of the submount 44 abuts on the horizontal step surface connecting the upper side surface and the lower side surface. The semiconductor optical device 42 and the wiring 56 are not arranged on the edge of the lower surface of the submount 44 with which the submount support 54 abuts.

The exterior case 40 is made of, for example, a material having high thermal conductivity such as metal. Also, the submount 44 is made of an insulating material having high thermal conductivity, such as a ceramic material such as aluminum nitride or aluminum oxide. By forming the exterior case 40 and the submount 44 from a material with high thermal conductivity and contacting them with the submount support base 54, the heat generated in the semiconductor optical element 42 can be dissipated to the outside of the OSA 30. can be made In addition, the submount 44 can be adhered to the submount support base 54, in which case it is preferable that the adhesive member also be made of a material with high thermal conductivity.

Note that the outer case 40 can be configured to include a main body having an opening at the top and a lid 40u that closes the opening. In this configuration, the submount 44 and the like are housed in the concave portion of the main body of the exterior case 40 through the opening, and then the opening of the main body is sealed with the lid 40u.

The submount support base 54 may have a shelf-like shape that protrudes horizontally from the inner side surface (plane parallel to the XZ plane) of the exterior case 40, and the edge of the submount 44 may be placed on the horizontal surface of the shelf. can. Also, the submount support base 54 has a shape like a pillar or wall protruding upward from the inner bottom surface (surface parallel to the XY plane) of the exterior case 40, and the edge of the submount 44 is placed on the horizontal surface provided on the top. It can also be structured.
The submount 44 is suspended in the exterior case 40 by the submount support base 54, and the position of the semiconductor optical element 42 in the Z-axis direction can be set, for example, at the center of the exterior case 40. The element 42 can be placed away from the bottom surface of the outer case 40 .

FIG. 7 is a schematic top view of the exterior case 40 with the lid 40u removed, showing the planar shape of the submount support base 54. As shown in FIG. In the example shown in FIG. 7, the submount support 54 is formed linearly along the side surface of the exterior case 40 parallel to the X-axis, and the width of the step surface of the submount support 54 is basically a constant value. be. That is, even if the position in the X-axis direction changes, the dimension of the step surface in the Y-axis direction does not change.

Further, the submount support 54 can be configured to abut only part of the edges in the X-axis direction of the edges of the submount 44 at both ends in the Y-axis direction. 54 is abutted on the entire edge with respect to the X-axis direction as shown in FIG. Thereby, the contact area between the submount 44 and the submount support 54 can be increased, and the efficiency of heat conduction from the submount 44 to the exterior case 40 can be improved.

Further, the submount support 54 of FIG. 7 extends to the location of the condenser lens 50 as shown in FIG. For example, the condenser lens 50 can be a lens array in which lenses corresponding to the four semiconductor optical elements 42 on the upper surface of the submount 44 and lenses corresponding to the four semiconductor optical elements 42 on the lower surface are integrally constructed. . The submount support base 54 abuts on the edges of the condenser lens 50 forming the lens array at both ends in the Y-axis direction, and supports the condenser lens 50 at a height corresponding to the submount 44 . Also, the condenser lens 50 can be configured separately with a lens array corresponding to the four semiconductor optical devices 42 on the upper surface of the submount 44 and a lens array corresponding to the four semiconductor optical devices 42 on the lower surface. In this case, the condenser lens 50 forming the upper lens array can be supported by the submount support 54 , and the condenser lens 50 forming the lower lens array can be installed on the bottom surface of the outer case 40 .

As described above, the submount support bases 54 are arranged separately in the Y-axis direction, and the exterior case 40 having a structure in which the submounts 44 are supported by the edges of the lower surfaces of the submounts 44 is provided at the center of the lower surface in the Y-axis direction. A submount 44 on which the semiconductor optical device 42 and wiring 56 are arranged can be accommodated. In other words, the outer case 40 can accommodate the submounts 44 having the semiconductor optical devices 42 arranged on both sides thereof, thereby making it possible to increase the speed of data transmission by increasing the number of WDM channels and to reduce the size of the OSA 30. Become.

[Second embodiment]
On the other hand, as a structure for supporting the submount 44 , in addition to the submount support base 54 , it is also possible to provide a pillar that abuts on the layout gap of the semiconductor optical element 42 and wiring 56 on the lower surface of the submount 44 .

The OSA 30 according to the second embodiment of the present invention has the support on the exterior case 40A. FIG. 8 is a schematic vertical sectional view of the OSA 30 according to the second embodiment. FIG. 8 shows a cross section along the XY plane and should be contrasted with FIG. 5 of the first embodiment. As shown in FIG. 8, the exterior case 40A includes a post 70 erected on the bottom between the two submount supports 54 and in contact with the bottom surface of the submount 44A.

FIG. 9 is a schematic top view of the exterior case 40A shown in FIG. 8, showing a state in which the lid 40u is removed, as in FIG. 8 shows a cross section along line VIII-VIII of FIG. For example, the post 70 is provided in the center of the exterior case 40A in the Y-axis direction, and is located at a position where the four channels of the semiconductor optical devices 42 and the wirings 56 provided on the lower surface of the submount 44A are divided into two channels each. 44A. Specifically, in the examples shown in FIGS. 8 and 9, the central two semiconductor optical devices 42-6 and 42-7 of the four semiconductor optical devices 42-5 to 42-8 arranged in the Y-axis direction The horizontal surface of the upper end of the support 70 is abutted between .

Like the submount support base 54, the post 70 has a function of supporting the submount 44A and a function of dissipating heat from the submount 44A. The submount 44A, the column 70, and the submount support base 54 can be adhered in the same manner as the submount 44 and the submount support base 54 described above.

[Third embodiment]
In the second embodiment, by providing the struts 70, the contact area between the exterior case 40A and the submount 44A is increased, and heat radiation efficiency can be improved. In this respect, heat radiation efficiency can be improved by increasing the contact area between the submount support base 54 and the submount 44 . The exterior case 40B of the OSA 30 according to the third embodiment of the present invention is formed such that the width direction dimension of a part of the submount support 54B is larger than the other part, and the submount support 54B and the submount 44B are separated from each other. We are trying to increase the contact area.

FIG. 10 is a schematic top view of the exterior case 40B of this embodiment, showing a state in which the lid 40u is removed, as in FIGS. 7 and 9. FIG. Regarding the dimension in the Y-axis direction, the end portion 54w of the submount support 54B on the terminal board 34 side is larger than the other portions of the submount support 54B.

As described in the first embodiment, a plurality of semiconductor optical devices 42 are arranged in the Y-axis direction on both main surfaces of the submount 44B, and one end is connected to the plurality of semiconductor optical devices. A wiring group composed of the wirings 56 is arranged in parallel in the Y-axis direction. In this embodiment, the width of the wiring group arrangement area on the lower surface of the submount 44B is narrowed on the terminal board 34 side so that the wide end 54w of the submount support base 54B does not come into contact with the wiring 56. FIG.

The characteristic configuration of this embodiment can be used together with the characteristic configuration of the second embodiment, and FIG. 11 is a schematic top view of an OSA 30 showing an example of the configuration. Features of this embodiment will be described more specifically with reference to FIG. 11 shows the outer case 40C and the submount 44C, and other components such as the condenser lens 50 and the optical multiplexer 52 are omitted.

The outer case 40C has a submount support base 54B similar to the outer case 40B of FIG. That is, the submount support 54B of the exterior case 40C has a wide end portion 54w on the terminal board 34 side, like the exterior case 40B shown in FIG. In addition, the exterior case 40C has a column 70 in the central portion in the Y-axis direction.

Although FIG. 11 shows the layout of the semiconductor optical device 42 and wiring 56 on the top surface of the submount 44C, the layout of the semiconductor optical device 42 and wiring 56 on the bottom surface of the submount 44C is the same as that on the top surface.

The arrangement area of the wiring group composed of the wiring 56 consists of a wide portion 74 located on the optical fiber connector 48 side and having a width corresponding to the arrangement width of the semiconductor optical devices 42, and a wide portion 74 located on the terminal substrate 34 side and having a width larger than the wide portion 74. narrow constriction 72 . On the other hand, the submount support 54B extending in the X-axis direction has a wide end 54w facing the constricted portion 72. As shown in FIG. That is, the submount support base 54B has a larger width dimension at the portion facing the narrowed portion 72 than at the portion facing the wide portion 74 . Incidentally, the narrowed portion 72 of the wiring group is formed by narrowing the width and arrangement intervals of the wirings 56 from those of the wide portion 74 .

It should be noted that the present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the configurations described in the embodiments can be replaced with configurations that are substantially the same, configurations that produce the same effects, or configurations that can achieve the same purpose.

10 optical module, 12 case, 14 pull tab, 16 slider, 18 optical transmission device, 20 electrical connector, 22 circuit board, 24 driver IC, 26 printed board, 28 flexible board, 30 optical subassembly (OSA), 32 optical fiber, 34 terminal board, 40 exterior case, 42 semiconductor optical device, 44 submount, 48 optical fiber connector, 50 condenser lens, 52 optical multiplexer, 54 submount support, 56, 58 wiring, 70 strut, 72 constriction, 74 Wide part.

Claims (7)

a plurality of semiconductor optical elements arranged with their optical axes parallel;
a submount having the semiconductor optical device mounted on both main surfaces thereof;
a housing that houses the submount,
The housing has a first step including a first top surface protruding from an inner side surface of the housing and a first inner side surface extending between the bottom surface inside the housing and the first top surface, the first step is adapted to support a first end of the submount;
The housing has a second step including a second top surface protruding from the side surface and a second inner side surface extending between the bottom surface and the second top surface, and the second step includes the sub adapted to support the second end of the mount;
An optical subassembly characterized by: The optical subassembly of claim 1, wherein
The optical sub-mount according to claim 1, wherein the housing includes a post erected between the first step and the second step and abutting against one of the main surfaces of the submount. assembly. 3. An optical subassembly according to claim 1 or claim 2,
On one of the main surfaces of the submount, a plurality of the semiconductor optical devices are arranged in a width direction intersecting the optical axis, and a wiring group having one end connected to the plurality of semiconductor optical devices is provided. arranged side by side in the width direction,
The arrangement region of the wiring group on the main surface includes a wide portion located on the one end side of the wiring group and having a width corresponding to the arrangement width of the semiconductor optical devices, and a wide portion located on the other end side of the wiring group. a narrow portion narrower than the wide portion;
The first step and the second step extend in the optical axis direction together with the first end and the second end , and extend from the portion facing the narrowed portion to the portion facing the narrowed portion. that the dimension in the width direction is large,
An optical subassembly characterized by: An optical subassembly according to any one of claims 1 to 3,
Having a lens for condensing the output light of the semiconductor optical device,
The lens for the semiconductor optical device mounted on one of the principal surfaces of the submount is provided on the bottom surface, and the lens for the semiconductor optical device mounted on the other principal surface is provided on the first step and the being supported by the second step ;
An optical subassembly characterized by: a plurality of semiconductor optical elements arranged with their optical axes parallel;
a submount on which the semiconductor optical device is mounted on both main surfaces;
a housing that houses the submount,
The housing includes two projections or steps separated in a width direction intersecting the optical axis and provided on a side surface or a bottom surface inside the housing, and A sub-mount support that abuts on the edges of both ends in the width direction,
The optical subassembly according to claim 1, wherein the housing includes a post erected on the bottom surface between the two submount supports and abutted against the one main surface of the submount. a plurality of semiconductor optical elements arranged with their optical axes parallel;
a submount on which the semiconductor optical device is mounted on both main surfaces;
a housing that houses the submount,
The housing includes two projections or steps separated in a width direction intersecting the optical axis and provided on a side surface or a bottom surface inside the housing, and A sub-mount support that abuts on the edges of both ends in the width direction,
A plurality of the semiconductor optical devices are arranged in the width direction on the one main surface of the submount, and a wiring group having one end connected to the plurality of semiconductor optical devices is arranged in the width direction. are placed in the
The arrangement area of the wiring group on the main surface includes a wide portion located on the one end side of the wiring group and having a width corresponding to the arrangement width of the semiconductor optical devices, and a wide portion located on the other end side of the wiring group. a narrow portion narrower than the wide portion;
The submount support extends in the optical axis direction together with the edge portion, and has a larger dimension in the width direction at a portion facing the narrow portion than at a portion facing the wide portion;
An optical subassembly characterized by: a plurality of semiconductor optical elements arranged with their optical axes parallel;
a submount on which the semiconductor optical device is mounted on both main surfaces;
a lens that collects output light from the semiconductor optical device;
a housing that houses the submount,
The housing includes two projections or steps separated in a width direction intersecting the optical axis and provided on a side surface or a bottom surface inside the housing, and A sub-mount support that abuts on the edges of both ends in the width direction,
The lens for the semiconductor optical device mounted on the one main surface of the submount is mounted on the bottom surface, and the lens for the semiconductor optical device mounted on the other main surface is mounted on the submount support base. be supported,
An optical subassembly characterized by:

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