WO2013099497A1

WO2013099497A1 - Optical module

Info

Publication number: WO2013099497A1
Application number: PCT/JP2012/080644
Authority: WO
Inventors: 肇荒生
Original assignee: 住友電気工業株式会社
Priority date: 2011-12-28
Filing date: 2012-11-27
Publication date: 2013-07-04
Also published as: JP2013140208A

Abstract

One purpose of the present invention is to provide an optical module which can prevent heat generated inside the optical module from heating said module to a high-temperature state. This optical module is provided with a CDR device (50b), a drive IC (50a) which drives a light emitting and receiving element (52), a circuit substrate (24) having a first area (A1) where the CDR device (50b) is mounted and a second area (A2) where the drive IC (50a) is mounted, and a metal housing (28) which houses at least a portion of the circuit substrate (24). The optical module further has a first heat dissipation sheet (56) which is mounted on the surface opposite of the surface where the CDR device (50b) is mounted in the first area (A1), and a second heat dissipation sheet (57) which is mounted on the surface opposite of the surface where the drive IC (50a) is mounted in the second area (A2), wherein at least a portion of the first heat dissipation sheet (56) and the second heat dissipation sheet (57) contact the metal housing (28).

Description

Optical module

The present invention relates to an optical module including a circuit board on which an optical element is mounted.

In recent years, optical modules used in network equipment have been increasing in number of channels, speed, and size. As an example of an optical module that supports multi-channel, high-speed, and miniaturization, an optical element that is provided on a circuit board and consists of a light-receiving element and a light-emitting element, and an optical signal from an optical fiber is optically connected There exists an optical module provided with the mirror for doing (refer patent document 1).

Japanese Unexamined Patent Publication No. 2010-010254

In an optical module having a photoelectric conversion unit that converts an electrical signal into an optical signal, it is necessary to design the entire module in consideration of heat generated in the photoelectric conversion unit. In addition, electronic components having different sizes and heights must be arranged in a limited design space. In the optical module disclosed in Patent Document 1, an IC chip is provided on the back side near the center of the circuit board, and a spacer having a heat dissipation function is provided on the back side of the region where the support plate is mounted on the circuit board. Yes.

However, in the configuration of Patent Document 1 described above, the spacer having a heat dissipation function is disposed at a position separated from the IC chip that generates heat, and the heat dissipation path of the IC chip is not secured. If the heat dissipation path of the electronic component that generates heat is not secured, there is a possibility that heat is accumulated inside the optical module, and a partially hot place is generated.

An object of the present invention is to provide an optical module capable of preventing heat generated in the optical module from being accumulated inside and becoming a high temperature state.

In order to achieve the above object, an optical module of the present invention includes a first heat generating element including a waveform shaper, a second heat generating element including a semiconductor element for driving the optical element, and the first heat generating element. A circuit board having a first area on which the second heat generating element is mounted, and a metal housing that houses at least a part of the circuit board, A first heat dissipating sheet mounted on a surface opposite to a surface on which the first heat generating element is mounted in the first region, and a surface on which the second heat generating element is mounted in the second region. And a second heat dissipating sheet mounted on the opposite surface, wherein at least a part of the first heat dissipating sheet and the second heat dissipating sheet are in contact with the metal housing.

In the optical module of the present invention, no heat generating component is mounted on the surface of the first region opposite to the surface on which the first heat generating element is mounted, and the second region in the second region. It is preferable that the heat generating component is not mounted on the surface opposite to the surface on which the heat generating element is mounted.

In the optical module of the present invention, the surface on which the first heat generating element is mounted in the first region is opposite to the surface on which the second heat generating element is mounted in the second region. It may be a surface.

Further, in the optical module of the present invention, it is preferable that the direction in which the first heat radiating sheet extends from the first heat generating element is a direction away from the second heat radiating sheet.

In the optical module of the present invention, the first heat generating element is a heat generating element that generates a larger amount of heat than the second heat generating element, and a third region is mounted in the first region where the first heat generating element is mounted. The one on which the heat dissipation sheet is mounted is preferable.

In the optical module of the present invention, it is preferable that the direction in which the third heat radiating sheet extends from the first heat generating element is a direction away from the second heat radiating sheet.

In the optical module of the present invention, the metal housing has a step portion, and at least a part of the third heat radiation sheet mounted in the first region is in contact with the step portion. preferable.

According to the optical module of the present invention, it is possible to prevent the heat generated in the optical module from being accumulated inside and becoming a high temperature state.

It is a perspective view which shows the optical module which concerns on this embodiment. It is a perspective view which shows the state which removed the resin housing. It is a perspective view which shows the state which removed the metal housing. 4A is a view of the substrate shown in FIG. 3 as viewed from above, and FIG. 4B is a view of the substrate shown in FIG. 3 as viewed from the side. It is the figure which looked at the circuit board and fixing member shown in FIG. 3 from the side. It is sectional drawing of the optical module shown in FIG. It is a figure which shows the modification 1 of the thermal radiation sheet shown in FIG. It is a figure which shows the modification 2 of the thermal radiation sheet shown in FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements will be denoted by the same reference numerals, and redundant description will be omitted.

An optical module 1 shown in FIG. 1 is used for transmission of signals (data) in optical communication technology and the like, and is electrically connected to an electronic device such as a personal computer to be connected to input / output electric signals. An optical signal is transmitted after being converted into a signal.

As shown in FIG. 1, the optical module 1 includes an optical cable 3 and a connector module 5. The optical module 1 is configured by attaching the end of a single-core or multi-core optical cable 3 to a connector module 5.

As shown in FIGS. 1 to 3, the optical cable 3 includes a plurality (four in this case) of optical fiber cores (optical fibers) 7 and a resin sheath 9 that covers the optical fiber cores 7. And an ultrafine-diameter tensile fiber (Kevlar) 11 interposed between the optical fiber core wire 7 and the jacket 9, and a metal braid 13 interposed between the jacket 9 and the tensile fiber 11. ing. That is, in the optical cable 3, the optical fiber core wire 7, the tensile strength fiber 11, the metal braid 13, and the jacket 9 are arranged in this order from the center toward the outside in the radial direction.

As the optical fiber core 7, an optical fiber (AGF: All Glass Fiber) whose core and clad are quartz glass, an optical fiber (HPCF: Hard Clad Fiber) whose clad is made of hard plastic, and the like can be used. When a thin HPCF having a glass core diameter of 80 μm is used, it is difficult to break even if the optical fiber core wire 7 is bent to a small diameter. The jacket 9 is made of, for example, PVC (polyvinylchloride) which is a non-halogen flame retardant resin. The outer diameter of the jacket 9 is about 4.2 mm, and the thermal conductivity of the jacket 9 is, for example, 0.17 W / m · K. The tensile strength fiber 11 is an aramid fiber, for example, and is built in the optical cable 3 in a bundled state.

The metal braid 13 is formed of, for example, a tin-plated conductive wire, and has a braid density of 70% or more and a knitting angle of 45 ° to 60 °. The outer diameter of the metal braid 13 is about 0.05 mm. The thermal conductivity of the metal braid 13 is, for example, 400 W / m · K. The metal braid 13 編 is preferably arranged at a high density in order to ensure good heat conduction. For example, the metal braid 13 is preferably composed of a rectangular tin-plated conductor.

The connector module 5 includes a housing 20, an electrical connector 22 provided on the front end (tip) side of the housing 20, and a circuit board 24 accommodated in the housing 20.

The housing 20 includes a metal housing (first housing) 26 and a resin housing (second housing) 28. The metal housing 26 includes a housing member 30 and a fixing member 32 that is connected to the rear end portion of the housing member 30 and fixes the optical cable 3. The metal housing 26 is formed of a metal material having high thermal conductivity (preferably 100 W / m · K or more) such as steel (Fe-based), tin (tin-plated copper), stainless steel, copper, brass, and aluminum. The metal housing 26 constitutes a heat conductor.

The housing member 30 is a cylindrical hollow member having a substantially rectangular cross section. The housing member 30 defines a housing space S for housing the circuit board 24 and the like. An electrical connector 22 is provided on the front end side of the housing member 30, and a fixing member 32 is connected to the rear end side of the housing member 30. Further, as shown in FIG. 6, the housing member 30 has a stepped portion 26 a near the upper portion of the CDR device 50 b mounted on the circuit board 24, and becomes slightly thin toward the electrical connector 22 side. ing.

The fixing member 32 includes a plate-like base portion 34, a cylindrical portion 36, a pair of first projecting pieces 38 projecting forward from both sides of the base portion 34, and a pair of second tension members projecting rearward from both sides of the base portion 34. And a protruding piece 40. The pair of first projecting pieces 38 are respectively inserted from the rear part of the housing member 30 and are in contact with and connected to the housing member 30. A pair of 2nd overhang | projection piece 40 is connected with the boot 46 of the resin housing 28 mentioned later. The fixing member 32 includes a base portion 34, a cylindrical portion 36, a first overhanging piece 38, and a second overhanging piece 40 that are integrally formed of sheet metal.

The cylindrical portion 36 has a substantially cylindrical shape and is provided so as to protrude rearward from the base portion 34. The cylindrical portion 36 holds the optical cable 3 in cooperation with the caulking ring 42. Specifically, after the outer sheath 9 is peeled off, the optical fiber core wire 7 of the optical cable 3 is inserted into the cylindrical portion 36 and the tensile strength fiber 11 is disposed along the outer peripheral surface of the cylindrical portion 36. And the crimping ring 42 is arrange | positioned on the tensile strength fiber 11 arrange | positioned at the outer peripheral surface of the cylinder part 36, and the crimping ring 42 is crimped. Thereby, the tensile strength fiber 11 is sandwiched and fixed between the cylindrical portion 36 and the caulking ring 42, and the optical cable 3 is held and fixed to the fixing member 32.

The end of the metal braid 13 of the optical cable 3 is joined to the base 34 with solder. Specifically, the metal braid 13 is disposed so as to cover the outer periphery of the caulking ring 42 (tubular portion 36) in the fixing member 32, and its end is extended to one surface (rear surface) of the base portion 34. Joined by solder. Thereby, the fixing member 32 and the metal braid 13 are thermally connected. Further, the fixing member 32 is coupled to the rear end portion of the accommodating member 30, whereby the accommodating member 30 and the fixing member 32 are physically and thermally connected. That is, the housing member 30 and the metal braid 13 of the optical cable 3 are thermally connected.

The resin housing 28 is made of a resin material such as polycarbonate, and covers the metal housing 26. The resin housing 28 includes an exterior housing 44 and a boot 46 connected to the exterior housing 44. The exterior housing 44 is provided so as to cover the outer surface of the housing member 30. The boot 46 is connected to the rear end portion of the exterior housing 44 and covers the fixing member 32 of the metal housing 26. The rear end portion of the boot 46 and the outer cover 9 of the optical cable 3 are bonded by an adhesive (not shown).

The electrical connector 22 is a part that is inserted into a connection target (such as a personal computer) and is electrically connected to the connection target. The electrical connector 22 is disposed on the front end side of the housing 20 and protrudes forward from the housing 20. The electrical connector 22 is electrically connected to the circuit board 24 by a contact 22a.

The circuit board 24 is accommodated in the accommodating space S of the metal housing 26 (accommodating member 30). A control semiconductor 50 and a light emitting / receiving element 52 (an example of an optical element) are mounted on the circuit board 24. The circuit board 24 electrically connects the control semiconductor 50 and the light emitting / receiving element 52. The circuit board 24 has a substantially rectangular shape in plan view and has a predetermined thickness. The circuit substrate 24 is an insulating substrate such as a glass epoxy substrate or a ceramic substrate, and circuit wiring is formed on the surface or inside thereof by gold (Au), aluminum (Al), copper (Cu), or the like. . The control semiconductor 50 and the light emitting / receiving element 52 constitute a photoelectric conversion unit.

The control semiconductor 50 includes a drive IC (Integrated Circuit) 50a (an example of a second heating element), a CDR (Clock Data Recovery) device 50b (an example of a first heating element), which is a waveform shaper, and the like. . The CDR device 50b may generate a larger amount of heat during operation than the drive IC 50a. The control semiconductor 50 is disposed on the front end side of the surface 24 a in the circuit board 24. The control semiconductor 50 is electrically connected to the electrical connector 22.

The light emitting / receiving element 52 includes a plurality (here, two) of light emitting elements 52a and a plurality (here, two) of light receiving elements 52b. The light emitting element 52a and the light receiving element 52b are disposed on the rear end side of the surface 24a in the circuit board 24. As the light emitting element 52a, for example, a light emitting diode (LED: Light Emitting Diode), a laser diode (LD: Laser Diode), a surface emitting laser (VCSEL: Vertical Cavity Surface Emitting LASER), or the like can be used. As the light receiving element 52b, for example, a photodiode (PD: Photo Diode) can be used.

The light emitting / receiving element 52 is optically connected to the optical fiber core wire 7 of the optical cable 3. Specifically, as shown in FIG. 4B, a lens array component 55 is arranged on the circuit board 24 so as to cover the light emitting / receiving element 52 and the driving IC 50a. The lens array component 55 is provided with a reflective film 55a that reflects and bends the light emitted from the light emitting element 52a or the light emitted from the optical fiber core wire 7. A connector part 54 is attached to the end of the optical fiber core 7, and the connector part 54 and the lens array part 55 are positioned and coupled by a positioning pin, whereby the optical fiber core 7 and the light receiving and emitting element 52 are connected. Optically connected. It is preferable that the lens array component 55 includes collimating lenses that convert the incident light into parallel light and collect and emit the parallel light at the light incident portion and the light emission portion. Such a lens array component 55 can be integrally formed by resin injection molding.

As shown in FIG. 6, a first heat radiation sheet 56 is disposed between the back surface 24b of the circuit board 24 and the housing member 30 (metal housing 26). The first heat radiating sheet 56 is mounted on the surface opposite to the surface on which the CDR device 50b is mounted in the first region A1 illustrated in FIG. 4 (see FIG. 4). The first heat radiation sheet 56 is in contact with the back surface 24 b of the circuit board 24 and the housing member 30. The first heat radiation sheet 56 extends toward the electrical connector 22 starting from the CDR device 50b. That is, it extends in a direction away from the second heat radiation sheet 57 described later.

Further, as shown in FIG. 6, a second heat dissipating sheet 57 is disposed between the back surface 24 b of the circuit board 24 and the housing member 30. The second heat radiating sheet 57 is mounted on the surface opposite to the surface on which the drive IC 50a is mounted in the second region A2 illustrated in FIG. The second heat radiation sheet 57 is in contact with the back surface 24 b of the circuit board 24 and the housing member 30.

Further, as shown in FIG. 6, a third heat dissipation sheet 58 is disposed between the surface 24 a of the circuit board 24 and the housing member 30. A part of the third heat radiation sheet 58 is mounted on the upper surface of the CDR device 50b and is in contact with the housing member 30 and the CDR device 50b. Further, the third heat radiation sheet 58 mounted on the CDR device 50 b is in contact with the entire step portion 26 a of the housing member 30. The third heat radiation sheet 58 extends toward the electrical connector 22 with the CDR device 50b as a starting point, and is in contact with the surface 24a of the circuit board 24.

The first heat radiating sheet 56, the second heat radiating sheet 57, and the third heat radiating sheet 58 are heat conductors formed of a material having thermal conductivity and flexibility. Further, the upper surface of the first heat radiation sheet 56 is physically and thermally connected to the back surface 24 b of the circuit board 24, and the lower surface is physically and thermally connected to the inner surface of the housing member 30. ing. The circuit board 24 and the metal housing 26 are thermally connected by the first heat radiation sheet 56. That is, the heat generated from the CDR device 50 b mounted on the surface 24 a of the circuit board 24 is transmitted to the housing member 30 via the circuit board 24 and the first heat dissipation sheet 56.

Similarly, the upper surface of the second heat radiation sheet 57 is physically and thermally connected to the back surface 24 b of the circuit board 24, and the lower surface is physically and thermally connected to the inner surface of the housing member 30. It is connected. The circuit board 24 and the metal housing 26 are thermally connected by the second heat radiation sheet 57. That is, heat generated from the driving IC 50 a mounted on the surface 24 a of the circuit board 24 is transmitted to the housing member 30 through the circuit board 24 and the second heat dissipation sheet 57.

A part of the upper surface of the third heat radiation sheet 58 is physically and thermally connected to the inner surface near the step portion 26a of the housing member 30, and the lower surface thereof is connected to the upper surface of the CDR device 50b and the circuit board. It is physically and thermally connected to 24 surfaces 24a. The circuit board 24 and the metal housing 26 are thermally connected by the third heat dissipation sheet 58. Further, the CDR device 50b and the metal housing 26 are thermally connected. That is, the heat generated from the CDR device 50 b is transmitted to the accommodation member 30 through the third heat dissipation sheet 58.

Note that the term “thermally connected” here means that a path capable of transferring heat is established by physical connection. Therefore, in the present embodiment, heat transfer through a medium such as air is not thermally connected.

In the optical module 1 having the above configuration, an electrical signal is input from the electrical connector 22, and the control semiconductor 50 inputs an electrical signal via the wiring of the circuit board 24. The electrical signal input to the control semiconductor 50 is output from the control semiconductor 50 to the light emitting / receiving element 52 via the wiring of the circuit board 24 after the level is adjusted and the waveform shaping is performed by the CDR device 50b. . The light emitting / receiving element 52 that receives the electric signal converts the electric signal into an optical signal, and emits the optical signal from the light emitting element 52 a to the optical fiber core wire 7.

Further, the optical signal transmitted through the optical cable 3 is incident on the light receiving element 52b. The light emitting / receiving element 52 converts the incident optical signal into an electrical signal and outputs the electrical signal to the control semiconductor 50 via the wiring of the circuit board 24. In the control semiconductor 50, the electrical signal is output to the electrical connector 22 after predetermined processing is performed on the electrical signal.

Subsequently, a heat dissipation method in the optical module 1 will be described with reference to FIG. The heat generated by the CDR device 50b, the drive IC 50a, and the light emitting / receiving element 52 mounted on the circuit board 24 is first transmitted to the circuit board 24. The heat transmitted to the circuit board 24 is transmitted to the housing member 30 via the first heat dissipation sheet 56 and the second heat dissipation sheet 57. Next, heat is transferred from the housing member 30 to the electrical connector 22 and the fixing member 32 connected thereto. The heat transmitted to the electrical connector 22 is radiated to an external device to which the electrical connector 22 is connected. The heat transmitted to the fixing member 32 is transmitted to the metal braid 13 of the optical cable 3 connected to the fixing member 32. Then, the heat transmitted to the metal braid 13 is radiated to the outside through the outer cover 9 of the optical cable 3. As described above, in the optical module 1, the heat generated in the control semiconductor 50 and the light emitting / receiving element 52, which are heating elements, is released to the outside.

As described above, in the present embodiment, the heat generated in the CDR device 50 b is transmitted to the first heat radiating sheet 56 mounted on the back side of the circuit board 24, and is transmitted from the first heat radiating sheet 56 to the metal housing 26. . Further, the heat generated in the drive IC 50 a and the light emitting / receiving element 52 is transmitted to the second heat radiating sheet 57 on the back side of the circuit board 24, and is transmitted from the second heat radiating sheet 57 to the metal housing 26. As described above, since a heat dissipation path for escaping the heat generated inside the optical module 1 to the metal housing 26 is secured, it is possible to prevent heat from being accumulated inside the optical module 1. In addition, since the first heat radiation sheet 56 and the second heat radiation sheet 57 are provided as separate components, the lens array component 55 and the CDR device 50b are not easily thermally connected.

Further, in the present embodiment, since the electronic component that generates heat is not mounted on the portion of the circuit board 24 on the back side of the region where the CDR device 50b is mounted, the first heat dissipation sheet 56 is in direct contact with the circuit board 24. A large area is secured, and heat dissipation efficiency is improved. In addition, since an electronic component that generates heat is not mounted on a portion of the circuit board 24 on the back side of the region where the driving IC 50a is mounted, a large area where the second heat dissipation sheet 57 directly contacts the circuit board 24 is secured, Heat dissipation efficiency is improved.

In the present embodiment, the example in which the first heat radiation sheet 56 and the second heat radiation sheet 57 are provided as separate components has been described. However, as in Modification 1 shown in FIG. The functions of the first heat dissipation sheet 56 and the second heat dissipation sheet 57 may be ensured. When one heat radiating sheet 59 is used, the number of parts can be reduced and the cost can be reduced.

In this embodiment, the CDR device 50b and the drive IC 50a are provided on the same surface of the circuit board 24. However, the CDR device 50b and the drive IC 50a may be provided on different surfaces of the circuit board 24. . For example, as in Modification 2 shown in FIG. 8, the CDR device 50 b may be provided on the back surface 24 b of the circuit board 24, and the first heat dissipation sheet 56 may be provided on the front surface 24 a of the circuit board 24. In Modification 2 shown in FIG. 8, the lower surface of the first heat dissipation sheet 56 is in contact with the surface 24 a of the circuit board 24, and the upper surface of the first heat dissipation sheet 56 is in contact with the inner surface of the housing member 30. In addition, a third heat dissipation sheet 58 is provided between the CDR device 50 b and the housing member 30. The upper surface of the third heat radiation sheet 58 is in contact with the CDR device 50 b and the back surface 24 b of the circuit board 24. Further, the lower surface of the third heat dissipation sheet 58 is in contact with the inner surface of the housing member 30.

By providing the CDR device 50b and the drive IC 50a on different surfaces of the circuit board 24, the region where the CDR device 50b is mounted and the region where the drive IC 50a is mounted are easily thermally separated.

In the present embodiment, the first heat radiation sheet 56 extends toward the electrical connector 22 from the CDR device 50b as a starting point. That is, since the first heat radiating sheet 56 extends in a direction away from the second heat radiating sheet 57, the heat generated in the CDR device 50 b is not easily transmitted to the second heat radiating sheet 57.

The CDR device 50b is an electronic component that generates a larger amount of heat than the drive IC 50a. In the present embodiment, as shown in FIG. 6, a third heat dissipation sheet 58 is provided between the CDR device 50b and the housing member 30. The CDR device 50b and the housing member 30 are physically and thermally connected. Therefore, the heat generated from the CDR device 50b is radiated to the electrical connector 22 side through the third heat radiating sheet 58 in addition to the first heat radiating sheet 56, and is hardly transmitted to the drive IC 50a.

Further, the third heat radiation sheet 58 extends toward the electrical connector 22 from the CDR device 50b as a starting point. That is, since the third heat radiating sheet 58 extends in a direction away from the second heat radiating sheet 57, the heat generated in the CDR device 50 b is not easily transmitted to the second heat radiating sheet 57.

In the present embodiment, the metal housing 26 has a stepped portion 26a, and a part of the third heat radiation sheet 58 is in contact with the stepped portion 26. Therefore, it is possible to secure a heat radiation path through which the heat generated in the CDR device 50 b is released to the metal housing 26 through the third heat radiation sheet 58.

While the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.

For example, a positioning pin for positioning the optical coupling member (lens array component 55) and the optical fiber holding member (connector component 54) is provided on the optical fiber holding member side in addition to the configuration provided on the optical coupling member side. May be. That is, as long as the positioning structure is formed on both, the specific form is not limited. At this time, if the mounting direction of the positioning structure is substantially parallel to the surface direction of the circuit board, the optical fiber holding member can be connected along the circuit board, so that the efficiency of assembly work (workability) is improved. To do.

In addition, the configuration in which the optical coupling member optically couples the light receiving and emitting elements having different optical axes and the optical fiber is not limited to the form of the lens array component 55. That is, it is not essential to provide the reflective film 55a, and a depressed portion having an inclined surface having the same angle as the reflective surface is formed at a position corresponding to the reflective film 55a of the lens array component, and the material of the lens array component 55 and the air A reflective surface using the difference in refractive index at the interface with the surface may be formed. In addition, instead of the reflective surface, an optical ferrule member having an arc-shaped optical fiber holding hole that can bend the optical fiber toward the optical axis direction of the light receiving and emitting element is used to transmit light from the optical fiber holding member side. A configuration may be adopted in which a fiber is inserted and the optical axis of the optical fiber is bent so as to coincide with the optical axis of the light receiving and emitting element. That is, it is not essential to provide the reflective film 55a in the optical coupling member. *

Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.
This application is based on Japanese Patent Application No. 2011-289582 filed on Dec. 28, 2011, the contents of which are incorporated herein by reference.

1: Optical module, 3: Optical cable, 5: Connector module, 7: Optical fiber core wire, 9: Outer sheath, 11: Tensile fiber, 13: Metal braid, 20: Housing, 24: Circuit board, A1: First Area, A2: second area, 26: metal housing, 26a: stepped portion, 28: resin housing, 30: housing member, 32: fixing member, 50: control semiconductor (electronic component), 50a: drive IC (first IC) 2), 50b: CDR device (example of first heating element), 52: light emitting / receiving element (example of optical element), 56: first heat dissipation sheet, 57: second heat dissipation sheet, 58: Third heat dissipation sheet, 60: Clip member, S: Storage space

Claims

A first heating element including a waveform shaper;
A second heating element including a semiconductor element that drives the optical element;
A circuit board having a first region in which the first heat generating element is mounted and a second region in which the second heat generating element is mounted;
A metal housing that houses at least a portion of the circuit board;
With
A first heat dissipating sheet mounted on a surface opposite to a surface on which the first heat generating element is mounted in the first region, and the second heat generating element is mounted on the second region. A second heat dissipating sheet mounted on the surface opposite to the surface,
An optical module in which at least a part of the first heat radiation sheet and the second heat radiation sheet is in contact with the metal housing.
A surface on which the first heat generating element is mounted on the surface opposite to the surface on which the first heat generating element is mounted is not mounted with a heat generating component, and the surface on which the second heat generating element is mounted on the second region. The optical module according to claim 1, wherein a heat generating component is not mounted on a surface opposite to the surface.
The surface on which the first heat generating element is mounted in the first region is a surface opposite to the surface on which the second heat generating element is mounted in the second region. The optical module as described.
The optical module according to any one of claims 1 to 3, wherein a direction in which the first heat dissipation sheet extends from the first heat generating element is a direction away from the second heat dissipation sheet.
The first heating element is a heating element that generates a larger amount of heat than the second heating element,
5. The optical module according to claim 1, wherein a third heat radiating sheet is mounted in a first region where the first heat generating element is mounted. 6.
The optical module according to claim 5, wherein a direction in which the third heat radiating sheet extends from the first heat generating element is a direction away from the second heat radiating sheet.
The optical module according to claim 5 or 6, wherein the metal housing has a step portion, and at least a part of the third heat radiation sheet mounted in the first region is in contact with the step portion.