JP2014119712A - Optical communication module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve heat dissipation of an optical communication module.SOLUTION: An optical communication module includes a housing 1, an optical transmission element 2, and a graphite sheet member GF1. The housing 1 includes a bottom wall 1a. The housing 1 accommodates the optical transmission element 2, the graphite sheet member GF1, a circuit board 4a, and the like. The graphite sheet member GF1 comprises an area P1a, an area P1b, and an area P1c. The area P1a includes a part arranged between the bottom wall 1a and the optical transmission element 2 and brought into contact with the optical transmission element 2, and is connected to the area P1b. The area P1c is connected to the area P1b and is brought into contact with the bottom wall 1a.

Description

The present invention relates to an optical communication module.

Patent Document 1 discloses a heat conducting member and an electronic device including the heat conducting member. The heat conducting member includes a graphite sheet and a diamond-like carbon thin film. The graphite sheet has electrical insulation and is relatively thin. The diamond-like carbon thin film has electrical insulation and is provided on the surface of the graphite sheet. The heat conducting member is in close contact with the heating element. The heat conducting member transmits heat generated during operation of the heat generating element to the cooling unit side.

JP 2003-008263 A

A conventional optical communication module includes heat radiating silicone, heat radiating gel, and the like. Heat from the optical transmission element is dissipated through heat dissipation silicone, heat dissipation gel, and the like. In recent years, with the increase in the loading density of optical communication modules in external devices and the increase in optical output of optical communication modules, higher heat dissipation is desired for optical communication modules compared to heat dissipation silicone, heat dissipation gel, etc. ing. Then, the objective of this invention is made | formed in view of said matter, and is improving the heat dissipation of an optical communication module.

An optical communication module according to the present invention includes a casing, an optical transmission element, and a graphite sheet member, the casing includes a bottom wall, and the casing includes the optical transmission element and the graphite sheet member. The graphite sheet member includes a first region, a second region, and a third region, and the first region is located between the bottom wall and the optical transmission element. A portion arranged and in contact with the optical transmission element is connected to the second region, and the third region is connected to the second region and contacts the bottom wall. According to the optical communication module of the present invention, the heat-transmitting optical transmission element is in contact with the first region, the first region is connected to the second region, and the second region is the third region. The third region contacts the bottom wall of the housing. Therefore, the heat of the optical transmission element is transmitted to the casing through the graphite sheet member. Therefore, the heat dissipation of the optical communication module is improved.

In the optical communication module according to the present invention, the first region includes a first portion and a second portion, and the first portion and the second portion are separated from the optical transmission element to the bottom. The first part is sandwiched between the optical transmission element and the second part, and is in contact with the optical transmission element and the second part. The portion is connected to the second region. As described above, the second portion connected to the second region can be thermally connected to the optical transmission element via the first portion. Therefore, even if the first part is fixed to the optical transmission element in advance, if the first part is brought into contact with the second part, the heat of the optical transmission element is increased by the first part. , Transmitted to the housing via the second portion, the second region, and the third region. Therefore, the heat dissipation of the optical communication module is improved.

In the optical communication module according to the present invention, the second region includes a first portion and a second portion, and the first portion is connected to the first region and the second portion. Is connected to the third region, the first portion and the second portion are in contact, the first region comprises a first surface, and the first portion is The second portion comprises a third surface, the third region comprises a fourth surface, the first surface contacts the optical transmission element, and The second surface is connected to the first surface, the second surface is in contact with the third surface, the third surface is connected to the fourth surface, and the fourth surface The surface of is in contact with the bottom wall. Thus, the first surface that contacts the optical transmission element connects to the second surface, the second surface contacts the third surface, and the third surface connects to the fourth surface. The fourth surface is in contact with the housing. Therefore, the heat of the optical transmission element is transmitted to the housing through the first surface, the second surface, the third surface, and the fourth surface. The heat of the optical transmission element is mainly transmitted in the surface direction of the graphite sheet member, and the graphite sheet has a relatively high thermal conductivity in the surface direction. Therefore, the heat dissipation of the optical communication module is improved.

In the optical communication module according to the present invention, the graphite sheet member includes a surface, and the graphite sheet member includes the optical transmission element and the bottom so that the surface is in contact with the optical transmission element and the bottom wall. It is bent between the walls. Thus, the surface of the graphite sheet member that contacts the optical transmission element contacts the housing. Therefore, the heat of the optical transmission element is transmitted to the casing through one surface of the graphite sheet member. The heat of the optical transmission element is mainly transmitted in the surface direction of the graphite sheet member, and the graphite sheet has a relatively high thermal conductivity in the surface direction. Therefore, the heat dissipation of the optical communication module is improved.

In the optical communication module according to the present invention, the first region includes a first portion and a second portion, and the first portion encloses the optical transmission element and is disposed on a side surface of the optical transmission element. The second part is in contact with the first part, provided between the first part and the bottom wall, connected to the second region, and the first part is A third portion and a fourth portion, and the third portion is sandwiched between the second portion and the optical transmission element, and is in contact with the second portion and the optical transmission element. The fourth portion is on the opposite side of the third portion and contacts the optical transmission element. In this way, the first part that wraps the optical transmission element and contacts the optical transmission element is in contact with the second part, the second part is connected to the second area, and the second area is The third region is in contact with the housing. Therefore, the heat of the optical transmission element is transmitted to the housing through the first portion, the second portion, the second region, and the third region. Since the first portion wraps the optical transmission element and comes into contact with the optical transmission element, the graphite sheet can come into contact with a relatively large amount of heat generated on the surface of the optical transmission element. Therefore, the heat dissipation of the optical communication module is improved.

ADVANTAGE OF THE INVENTION According to this invention, the heat dissipation of an optical communication module can be improved.

It is a figure for demonstrating typically the 1st structure of the optical communication module which concerns on embodiment. It is a figure for demonstrating typically the 2nd structure of the optical communication module which concerns on embodiment. It is a figure for demonstrating typically the 3rd structure of the optical communication module which concerns on embodiment. It is a figure for demonstrating typically the 4th structure of the optical communication module which concerns on embodiment. It is a figure for demonstrating typically the 5th structure of the optical communication module which concerns on embodiment. It is a figure for demonstrating the 2nd structure of the optical communication module which concerns on embodiment. It is a figure for demonstrating the effect of the optical communication module which concerns on embodiment. It is a figure for demonstrating the heat conductivity which concerns on embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the description of the drawings, if possible, the same elements are denoted by the same reference numerals, and redundant description is omitted. FIG. 1 is a diagram for schematically explaining the configuration of the optical communication module 11 according to the embodiment.

The optical communication module 11 includes a housing 1, a light transmitting element 2, a heat radiation sheet 3a, a heat radiation sheet 3b, a heat radiation sheet 3c, a circuit board 4a, a circuit board 4b, and a graphite sheet member GF1. The housing 1 houses the light transmitting element 2, the heat radiation sheet 3a, the heat radiation sheet 3b, the heat radiation sheet 3c, the circuit board 4a, the circuit board 4b, the light receiving element, and the graphite sheet member GF1. The housing 1 includes a bottom wall 1a and a bottom wall 1b. On the bottom wall 1a, the heat radiating sheet 3a, the graphite sheet member GF1, the light transmitting element 2, and the heat radiating sheet 3b are sequentially arranged in the normal direction Nx of the bottom wall 1a. On the bottom wall 1a, a graphite sheet member GF1, a heat radiation sheet 3c, a circuit board 4a, and a circuit board 4b are sequentially arranged in the normal direction Nx. The heat dissipation sheet 3c is sandwiched between the circuit board 4a and the graphite sheet member GF1. The heat dissipation sheet 3c is in contact with the circuit board 4a and the graphite sheet member GF1.

The graphite sheet member GF1 includes a region P1a (first region), a region P1b (second region), and a region P1c (third region). The region P1a includes a portion disposed between the bottom wall 1a and the optical transmission element 2 and in contact with the optical transmission element 2. The region P1a is connected to the region P1b. The region P1c is connected to the region P1b. The region P1c contacts the bottom wall 1a.

The optical communication module 11 includes the optical receiving element 5 shown in FIG. The optical transmission element 2 is a TOSA (Transmitter Optical Sub-Assembly). The optical receiving element 5 is a ROSA (Receiver Optical Sub-Assembly). The optical transmission element 2 includes a semiconductor laser 2a and a light emitting unit 2b. Laser light emitted from the semiconductor laser 2a is output to the outside via the light emitting portion 2b. The light receiving element 5 includes a light incident part 5a and a photodiode (not shown). The light incident through the light incident part 5a is detected by a photodiode.

The region P1a includes a surface SA1a and a surface SB1a. The region P1b includes a surface SA1b and a surface SB1b. The region P1c includes a surface SA1c and a surface SB1c.

The region P1a, the region P1b, and the region P1c constitute an integral graphite sheet, and this graphite sheet is the graphite sheet member GF1. The surface SA1a, the surface SA1b, and the surface SA1c constitute one surface of the graphite sheet member GF1. The surface SB1a, the surface SB1b, and the surface SB1c constitute another surface (back surface) of the graphite sheet member GF1.

The graphite sheet member GF1 includes a plurality of graphenes. In the graphite sheet member GF1, the plurality of graphenes are directed (in the thickness direction) from one surface (surface including the surface SA1a) to the other surface (surface including the surface SB1a) of the graphite sheet member GF1. Are stacked. The thickness of the graphite sheet member GF1 is the distance between one surface (surface including the surface SA1a) of the graphite sheet member GF1 and the other surface (surface including the surface SB1a) of the graphite sheet member GF1. In the graphite sheet member GF1, a stack of a plurality of graphenes can be covered with, for example, an aluminum thin film. It should be noted that such a configuration in which a stack of a plurality of graphenes is covered with an aluminum thin film is not an essential configuration in the graphite sheet member GF1.

The surface SA1a is in contact with the optical transmission element 2. Surface SB1c contacts bottom wall 1a. Heat generated from the optical transmission element 2 is transmitted to the graphite sheet member GF1 through the surface SA1a, is transmitted to the bottom wall 1a through the surface SB1c, and is transmitted to the heat sink 6 through the bottom wall 1a.

The graphite sheet member GF1 includes a graphite sheet (GF sheet). The graphite sheet member GF1 has, for example, heat in the X and Y directions as compared with the heat radiating gel / heat radiating sheet (corresponding to the heat radiating sheet 3a, the heat radiating sheet 3b, and the heat radiating sheet 3c) shown in FIG. High conductivity. The XY direction shown in FIG. 8 is a direction orthogonal to the thickness direction.

The thermal resistivity Rth of the graphite sheet member GF1 is, for example, a contact area S = 43.12 mm ² between the graphite sheet member GF1 and the heat source, and the thermal conductivity λ = 3 W / (m · K in the thickness direction of the graphite sheet member GF1. ) Is about 0.30 or more and 0.33 (° C./W) or less when the thickness t = 0.025 mm, and is about 0.91 or more and 1.2 (° C./W) when the thickness t = 0.13 mm. W) or less, and approximately 3.5 or more and 4.5 (° C./W) or less when the thickness t = 0.51 mm. In general, the thermal resistivity Rth of an object can be theoretically calculated by Rth = (object thickness t) / ((thermal conductivity λ of object) × (contact area S between object and heat source)). .

The region P1a is in close contact with the optical transmission element 2. The heat radiation sheet 3a, the region P1a, the light transmitting element 2, the heat radiation sheet 3b, and the bottom wall 1b are sequentially provided on the inner surface 1a1 of the bottom wall 1a toward the normal direction Nx. The heat dissipation sheet 3a has elasticity. The heat radiation sheet 3a contacts the surface SB1a and the inner surface 1a1. The heat radiation sheet 3a is compressed. Accordingly, the region P1a is pressed against the optical transmission element 2 by the elastic force E1 of the heat dissipation sheet 3a. The heat dissipation sheet 3b has elasticity. The heat radiating sheet 3b contacts the inner surface 1b1 of the bottom wall 1b and the optical transmission element 2. The heat dissipation sheet 3b is compressed. Accordingly, the optical transmission element 2 is pressed against the region P1a by the elastic force E2 of the heat dissipation sheet 3b. The region P1a is in close contact with the optical transmission element 2 by the elastic force E1 of the heat dissipation sheet 3a and the elastic force E2 of the heat dissipation sheet 3b.

The region P1c is in close contact with the bottom wall 1b. The heat radiation sheet 3c has elasticity. The heat radiation sheet 3c contacts the circuit board 4a and the inner surface 1a1. The circuit board 4a is fixed to the bottom wall 1a. The heat radiation sheet 3c is compressed. Accordingly, the region P1c is pressed against the bottom wall 1a by the elastic force E3 of the heat dissipation sheet 3c. The region P1c is in close contact with the bottom wall 1a by the elastic force E3 of the heat dissipation sheet 3c.

The region P1a is in close contact with the optical transmission element 2 that generates heat. The region P1a is connected to the region P1b. The region P1b is connected to the region P1c. The region P1c is in close contact with the bottom wall 1a. Thus, the region P1a in close contact with the optical transmission element 2 and the region P1c in close contact with the inner surface 1a1 intersect in the thickness direction, in other words, in the direction in which the graphene of the graphite sheet member GF1 extends. Thermally connected. Therefore, the heat of the optical transmission element 2 is efficiently transmitted to the bottom wall 1a and the heat sink 6 through the graphite sheet member GF1.

According to the configuration of the optical communication module 11 described above, the heat transmitting optical transmission element 2 is in contact with the region P1a, the region P1a is connected to the region P1b, the region P1b is connected to the region P1c, and the region P1c is The bottom wall 1a of the housing 1 is contacted. Therefore, the heat of the optical transmission element 2 is transmitted to the housing 1 via the graphite sheet member GF1. Therefore, the heat dissipation of the optical communication module 11 is improved.

FIG. 2 is a diagram for schematically explaining the configuration of the optical communication module 12 according to the embodiment. The optical communication module 12 includes a housing 1, an optical transmission element 2, a heat radiation sheet 3a, a heat radiation sheet 3b, a heat radiation sheet 3c, a circuit board 4a, a circuit board 4b, and a graphite sheet member GF2. The housing 1 houses the light transmitting element 2, the heat radiating sheet 3a, the heat radiating sheet 3b, the heat radiating sheet 3c, the circuit board 4a, the circuit board 4b, the light receiving element, and the graphite sheet member GF2. The housing 1 includes a bottom wall 1a and a bottom wall 1b. On the bottom wall 1a, the heat radiating sheet 3a, the graphite sheet member GF2, the light transmitting element 2, and the heat radiating sheet 3b are sequentially arranged in the normal direction Nx of the bottom wall 1a. On the bottom wall 1a, the graphite sheet member GF2, the heat radiating sheet 3c, the circuit board 4a, and the circuit board 4b are sequentially arranged in the normal direction Nx. The optical communication module 12 includes the optical receiving element 5 shown in FIG. The heat dissipation sheet 3c is sandwiched between the circuit board 4a and the graphite sheet member GF2. The heat dissipation sheet 3c is in contact with the circuit board 4a and the graphite sheet member GF2.

The graphite sheet member GF2 includes a region P2a (first region), a region P2b (second region), and a region P2c (third region). The region P2a includes a portion that is disposed between the bottom wall 1a and the optical transmission element 2 and that is in contact with the optical transmission element 2. The region P2a is connected to the region P2b. The region P2c is connected to the region P2b. The region P2c contacts the bottom wall 1a.

The region P2a includes a portion P2a1 (first portion) and a portion P2a2 (second portion). The part P2a1 and the part P2a2 are sequentially arranged from the optical transmission element 2 toward the bottom wall 1a (in the direction opposite to the normal direction Nx). The part P2a1 is sandwiched between the optical transmission element 2 and the part P2a2. The part P2a1 is in contact with the optical transmission element 2 and the part P2a2. The portion P2a2 is connected to the region P2b.

The portion P2a1 includes a surface SA2a1 and a surface SB2a1. The portion P2a2 includes a surface SA2a2 and a surface SB2a2. The region P2b includes a surface SA2b and a surface SB2b. The region P2c includes a surface SA2c and a surface SB2c. The surface SA2a1 is in contact with the optical transmission element 2. Surface SB2a1 and surface SA2a2 are in contact with each other. The surface SA2a2 is connected to the surface SA2b. The surface SA2b is connected to the surface SA2c. Surface SB2a2 is connected to surface SB2b. The surface SB2b is connected to the surface SB2c.

The portion P2a1 includes a plurality of graphenes. The portion P2a2 includes a plurality of graphenes. The region P2b includes a plurality of graphenes. The region P2c includes a plurality of graphenes. The portion P2a2, the region P2b, and the region P2c constitute an integral graphite sheet. In the portion P2a1, the plurality of graphenes are stacked from the surface SA2a1 to the surface SB2a1 (in the thickness direction). In the integral graphite sheet including the portion P2a2, the region P2b, and the region P2c, a plurality of graphenes are stacked from the surface SA2a2 side to the surface SB2a2 side (in the thickness direction). The thickness of the portion P2a1 is the distance between the surface SA2a1 and the surface SB2a1. The thickness of the integral graphite sheet composed of the portion P2a2, the region P2b, and the region P2c is the distance between the surface including the surface SA2a2 and the surface including the surface SB2a2.

In the step of attaching the optical transmission element 2 to the housing 1, when the portion P2a1 is attached in advance to the optical transmission device 2 and the portion P2a2 is fixed in advance to the housing 1, the surface SB2a1 of the portion P2a1; With the surface SA2a2 of the part P2a2, it becomes easy to slide the optical transmission element 2 on the surface SA2a2 of the part P2a2 by the contact of graphite having self-lubricating properties. Therefore, as shown in FIG. 6B, in the step of attaching the light transmitting element 2 to the housing 1, the light emitting part 2b and the light incident part 5a are respectively connected to the through hole H1 and the through hole H2. When it is necessary to insert the graphite sheet member GF2, the work of attaching the optical transmission element 2 to the housing 1 becomes relatively easy. This effect does not occur in the case shown in part (A) of FIG. Each of the light transmitting element 2, the light emitting part 2b, the light receiving element 5, the light incident part 5a, and the housing 1 can be as shown in part (A) of FIG. It can be shown in part B). Further, in the portion P2a1, a part of the plurality of graphene stacks can be covered with, for example, an aluminum thin film. Further, in the integrated graphite sheet including the portion P2a2, the region P2b, and the region P2c, A part of the stack can be covered with, for example, an aluminum thin film, but such a configuration in which the stack of a plurality of graphenes is covered with the aluminum thin film is not an essential configuration in the graphite sheet member GF2. . In particular, when an aluminum thin film is used in the configuration shown in FIG. 2, the contact surface (except at least the contact surface between the portion P2a1 and the portion P2a2) is used so as not to impair the self-lubricity between the graphites. Can be used.

The surface SA2a1 is in contact with the optical transmission element 2. Surface SB2c contacts bottom wall 1a. Heat generated from the optical transmission element 2 is transmitted to the graphite sheet member GF2 through the surface SA2a1, transmitted to the bottom wall 1a through the surface SB2c, and transmitted to the heat sink 6 through the bottom wall 1a.

The graphite sheet member GF2 includes a graphite sheet (GF sheet). The graphite sheet member GF2 has, for example, heat in the X and Y directions as compared with the heat radiating gel / heat radiating sheet (corresponding to the heat radiating sheet 3a, the heat radiating sheet 3b, and the heat radiating sheet 3c) illustrated in FIG. High conductivity. The XY direction shown in FIG. 8 is a direction orthogonal to the thickness direction.

The region P2a is in close contact with the optical transmission element 2. The heat radiating sheet 3a, the part P2a2, the part P2a2, the optical transmission element 2, the heat radiating sheet 3b, and the bottom wall 1b are sequentially provided on the inner surface 1a1 of the bottom wall 1a toward the normal direction Nx. The heat dissipation sheet 3a has elasticity. The heat radiation sheet 3a contacts the surface SB2a2 of the portion P2a2 of the region P2a and the inner surface 1a1. The part P2a2 is in contact with the part P2a1 of the region P2a. The portion P2a1 is in contact with the optical transmission element 2. The heat radiation sheet 3a is compressed. Therefore, the portion P2a1 of the region P2a and the portion P2a2 of the region P2a are brought into close contact with each other by the elastic force E1 of the heat dissipation sheet 3a. The region P2a is pressed against the optical transmission element 2 by the elastic force E1 of the heat dissipation sheet 3a. The heat dissipation sheet 3b has elasticity. The heat radiating sheet 3b contacts the inner surface 1b1 of the bottom wall 1b and the optical transmission element 2. The heat dissipation sheet 3b is compressed. Accordingly, the optical transmission element 2 is pressed against the region P2a by the elastic force E2 of the heat dissipation sheet 3b. The region P2a is in close contact with the optical transmission element 2 by the elastic force E1 of the heat dissipation sheet 3a and the elastic force E2 of the heat dissipation sheet 3b.

The region P2c is in close contact with the bottom wall 1b. The heat radiation sheet 3c has elasticity. The heat radiation sheet 3c contacts the circuit board 4a and the inner surface 1a1. The circuit board 4a is fixed to the bottom wall 1a. The heat radiation sheet 3c is compressed. Accordingly, the region P2c is pressed against the bottom wall 1a by the elastic force E3 of the heat dissipation sheet 3c. The region P2c is in close contact with the bottom wall 1a by the elastic force E3 of the heat dissipation sheet 3c.

The region P2a is in close contact with the optical transmission element 2 that generates heat. The region P2a is connected to the region P2b. The region P2b is connected to the region P2c. The region P2c is in close contact with the bottom wall 1a. Thus, the region P2a in close contact with the optical transmission element 2 and the region P2c in close contact with the inner surface 1a1 intersect in the thickness direction, in other words, in the direction in which the graphene of the graphite sheet member GF2 extends, Thermally connected. Therefore, the heat of the optical transmission element 2 is efficiently transmitted to the bottom wall 1a and the heat sink 6 through the graphite sheet member GF2.

According to the configuration of the optical communication module 12 described above, the heat transmitting optical transmission element 2 is in contact with the region P2a, the region P2a is connected to the region P2b, the region P2b is connected to the region P2c, and the region P2c is The bottom wall 1a of the housing 1 is contacted. Therefore, the heat of the optical transmission element 2 is transmitted to the housing 1 through the graphite sheet member GF2. The portion P2a2 connected to the region P2b can be thermally connected to the optical transmission element 2 via the portion P2a1. Therefore, even if the portion P2a1 is fixed to the optical transmission element 2 in advance, if the portion P2a1 is brought into contact with the portion P2a2, the heat of the optical transmission element 2 is changed to the portion P2a1, the portion P2a2, and the region P2b. And transmitted to the housing 1 via the region P3c. Therefore, the heat dissipation of the optical communication module 12 is improved.

FIG. 3 is a diagram for schematically explaining the configuration of the optical communication module 13 according to the embodiment. The optical communication module 13 includes a housing 1, an optical transmission element 2, a heat radiation sheet 3a, a heat radiation sheet 3b, a heat radiation sheet 3c, a circuit board 4a, a circuit board 4b, and a graphite sheet member GF3. The housing 1 houses the light transmitting element 2, the heat radiating sheet 3a, the heat radiating sheet 3b, the heat radiating sheet 3c, the circuit board 4a, the circuit board 4b, the light receiving element, and the graphite sheet member GF3. The housing 1 includes a bottom wall 1a and a bottom wall 1b. On the bottom wall 1a, the heat radiating sheet 3a, the graphite sheet member GF3, the light transmitting element 2, and the heat radiating sheet 3b are sequentially arranged in the normal direction Nx of the bottom wall 1a.
On the bottom wall 1a, a graphite sheet member GF3, a heat dissipation sheet 3c, a circuit board 4a, and a circuit board 4b are sequentially arranged in the normal direction Nx. The optical communication module 13 includes the optical receiving element 5 shown in FIG. The heat dissipation sheet 3c is sandwiched between the circuit board 4a and the graphite sheet member GF3. The heat dissipation sheet 3c contacts the circuit board 4a and the graphite sheet member GF3.

The graphite sheet member GF3 includes a region P3a (first region), a region P3b (second region), and a region P3c (third region). The region P3a is disposed between the bottom wall 1a and the optical transmission element 2 and is in contact with the optical transmission element 2. The region P3a is connected to the region P3b. The region P3c is connected to the region P3b. The region P3c is in contact with the bottom wall 1a.

The region P3b includes a part P3b1 (second part) and a part P3b2 (first part). The part P3b2 is connected to the region P3a. The portion P3b1 is connected to the region P3c. The part P3b1 and the part P3b2 are in contact with each other.

The region P3a includes a surface SA3a (first surface). The region P3a includes a surface SB3a. The portion P3b2 includes a surface SA3b2 (second surface). The portion P3b2 includes a surface SB3b2. The portion P3b1 includes a surface SA3b1. The portion P3b1 includes a surface SB3b1 (third surface). The region P3c includes a surface SA3c. The region P3c includes a surface SB3c (fourth surface).

The surface SA3a is in contact with the optical transmission element 2. The surface SA3b2 is connected to the surface SA3a. Surface SA3b2 is in contact with surface SB3b1. The surface SB3b1 is connected to the surface SB3c. Surface SB3c contacts bottom wall 1a.

The region P3a includes a plurality of graphenes. The portion P3b1 includes a plurality of graphenes. The portion P3b2 includes a plurality of graphenes. The region P3c includes a plurality of graphenes. Region P3a and portion P3b2 constitute an integral graphite sheet. The portion P3b1 and the region P3c constitute an integral graphite sheet. In the integral graphite sheet including the region P3a and the portion P3b2, a plurality of graphenes are stacked from the surface SA3a side to the surface SB3a side (in the thickness direction). In the integral graphite sheet including the portion P3b1 and the region P3c, a plurality of graphenes are stacked from the surface SA3c side to the surface SB3c side (in the thickness direction). The thickness of the integral graphite sheet composed of the region P3a and the portion P3b2 is the distance between the surface including the surface SA3a and the surface including the surface SB3a. The thickness of the integral graphite sheet composed of the portion P3b1 and the region P3c is the distance between the surface including the surface SA3c and the surface including the surface SB3c.

The surface SA3a is in contact with the optical transmission element 2. Surface SB3c contacts bottom wall 1a. Heat generated from the optical transmission element 2 is transmitted to the graphite sheet member GF3 via the surface SA3a, is transmitted to the bottom wall 1a via the surface SB3c, and is transmitted to the heat sink 6 via the bottom wall 1a.

The graphite sheet member GF3 includes a graphite sheet (GF sheet). The graphite sheet member GF3 has, for example, heat in the X and Y directions as compared with a heat radiating gel / heat radiating sheet (corresponding to the heat radiating sheet 3a, the heat radiating sheet 3b, and the heat radiating sheet 3c) illustrated in FIG. High conductivity. The XY direction shown in FIG. 8 is a direction orthogonal to the thickness direction.

The region P3a is in close contact with the optical transmission element 2. The heat radiating sheet 3a, the region P3a, the light transmitting element 2, the heat radiating sheet 3b, and the bottom wall 1b are sequentially provided on the inner surface 1a1 of the bottom wall 1a toward the normal direction Nx. The heat dissipation sheet 3a has elasticity. The heat radiation sheet 3a contacts the surface SB1a and the inner surface 1a1. The heat radiation sheet 3a is compressed. Accordingly, the region P3a is pressed against the optical transmission element 2 by the elastic force E1 of the heat dissipation sheet 3a. The heat dissipation sheet 3b has elasticity. The heat radiating sheet 3b contacts the inner surface 1b1 of the bottom wall 1b and the optical transmission element 2. The heat dissipation sheet 3b is compressed. Accordingly, the optical transmission element 2 is pressed against the region P3a by the elastic force E2 of the heat dissipation sheet 3b. The region P3a is in close contact with the optical transmission element 2 by the elastic force E1 of the heat dissipation sheet 3a and the elastic force E2 of the heat dissipation sheet 3b.

The region P3c is in close contact with the bottom wall 1b. The heat radiation sheet 3c has elasticity. The heat radiation sheet 3c contacts the circuit board 4a and the inner surface 1a1. The circuit board 4a is fixed to the bottom wall 1a. The heat radiation sheet 3c is compressed. Accordingly, the region P3c is pressed against the bottom wall 1a by the elastic force E3 of the heat dissipation sheet 3c. The region P3c is in close contact with the bottom wall 1a by the elastic force E3 of the heat dissipation sheet 3c. The portion P3b1 of the region P3b is in close contact with the portion P3b2 of the region P3b by the elastic force E3 of the heat dissipation sheet 3c.

The surface SA3a is in close contact with the optical transmission element 2 that generates heat. The surface SA3a is connected to the surface SA3b2. Surface SA3b2 is in close contact with surface SB3b1. The surface SB3b1 is connected to the surface SB3c. Surface SB3c is in close contact with inner surface 1a1. Thus, the surface SA3a that is in close contact with the optical transmission element 2 and the surface SB3c that is in close contact with the inner surface 1a1 cross in the thickness direction, in other words, in the direction in which the graphene of the graphite sheet member GF3 extends. Thermally connected. Therefore, the heat of the optical transmission element 2 is efficiently transmitted to the bottom wall 1a and the heat sink 6 through the graphite sheet member GF3.

According to the configuration of the optical communication module 13 described above, the heat transmitting optical transmission element 2 is in contact with the region P3a, the region P3a is connected to the region P3b, the region P3b is connected to the region P3c, and the region P3c is The bottom wall 1a of the housing 1 is contacted. Therefore, the heat of the optical transmission element 2 is transmitted to the housing 1 via the graphite sheet member GF3. The surface SA3a in contact with the optical transmission element 2 is connected to the surface SA3b2, the surface SA3b2 is in contact with the surface SB3b1, the surface SB3b1 is connected to the surface SB3c, and the surface SB3c is in contact with the housing 1. Therefore, the heat of the optical transmission element 2 is transmitted to the housing 1 through the surface SA3a, the surface SA3b2, the surface SB3b1, and the surface SB3c. The heat of the optical transmission element 2 is mainly transmitted to the surface direction of the graphite sheet member GF3 because the thermal conductivity of the graphite sheet is relatively low in the thickness direction. Therefore, the heat dissipation of the optical communication module 13 is improved.

FIG. 4 is a diagram for schematically explaining the configuration of the optical communication module 14 according to the embodiment. The optical communication module 14 includes a housing 1, an optical transmission element 2, a heat radiation sheet 3a, a heat radiation sheet 3b, a heat radiation sheet 3c, a circuit board 4a, a circuit board 4b, and a graphite sheet member GF4. The housing 1 houses the light transmitting element 2, the heat radiating sheet 3a, the heat radiating sheet 3b, the heat radiating sheet 3c, the circuit board 4a, the circuit board 4b, the light receiving element, and the graphite sheet member GF4. The housing 1 includes a bottom wall 1a and a bottom wall 1b. On the bottom wall 1a, the heat radiating sheet 3a, the graphite sheet member GF4, the light transmitting element 2, and the heat radiating sheet 3b are sequentially arranged in the normal direction Nx of the bottom wall 1a. On the bottom wall 1a, a graphite sheet member GF4, a heat dissipation sheet 3c, a circuit board 4a, and a circuit board 4b are sequentially arranged in the normal direction Nx. The optical communication module 14 includes the optical receiving element 5 shown in FIG. The heat dissipation sheet 3c is sandwiched between the circuit board 4a and the graphite sheet member GF4. The heat dissipation sheet 3c contacts the circuit board 4a and the graphite sheet member GF4.

The graphite sheet member GF4 includes a region P4a (first region), a region P4b (second region), and a region P4c (third region). The region P4a is disposed between the bottom wall 1a and the optical transmission element 2 and is in contact with the optical transmission element 2. The region P4a is connected to the region P4b. The region P4c is connected to the region P4b. The region P4c is in contact with the bottom wall 1a.

The region P4a includes a surface SA4a and a surface SB4a. The region P4b includes a surface SA4b and a surface SB4b. The region P4c includes a surface SA4c and a surface SB4c.

The region P4a, the region P4b, and the region P4c constitute an integral graphite sheet, and this graphite sheet is a graphite sheet member GF4. The surface SA4a, the surface SA4b, and the surface SA4c constitute one surface SA4 of the graphite sheet member GF4. The surface SB4a, the surface SB4b, and the surface SB4c constitute another surface (back surface) of the graphite sheet member GF4.

The graphite sheet member GF4 includes a plurality of graphenes. In the graphite sheet member GF4, the plurality of graphenes are stacked from one surface of the graphite sheet member GF4 toward the other surface (back surface) of the graphite sheet member GF4 (in the thickness direction). The thickness of the graphite sheet member GF4 is the distance between one surface (surface including the surface SA4a) of the graphite sheet member GF4 and the other surface (surface including the surface SB4a) of the graphite sheet member GF4. The graphite sheet member GF4 is bent between the optical transmission element 2 and the bottom wall 1a so that one surface including both the surface SA4a and the surface SA4c is in contact with the optical transmission element 2 and the bottom wall 1a. . Heat generated from the optical transmission element 2 is transmitted to the graphite sheet member GF4 via the surface SA4a, is transmitted to the bottom wall 1a via the surface SB4c, and is transmitted to the heat sink 6 via the bottom wall 1a.

The graphite sheet member GF4 includes a graphite sheet (GF sheet). The graphite sheet member GF4 has, for example, heat in the X and Y directions as compared with the heat radiating gel / heat radiating sheet (corresponding to the heat radiating sheet 3a, the heat radiating sheet 3b and the heat radiating sheet 3c) shown in FIG. High conductivity. The XY direction shown in FIG. 8 is a direction orthogonal to the thickness direction.

The region P4a is in close contact with the optical transmission element 2. The region P4c, the heat radiating sheet 3a, the region P3a, the optical transmission element 2, the heat radiating sheet 3b, and the bottom wall 1b are sequentially provided on the inner surface 1a1 of the bottom wall 1a toward the normal direction Nx. The heat dissipation sheet 3a has elasticity. The heat radiation sheet 3a is sandwiched between the region P4c and the region P4a. The heat dissipation sheet 3a contacts the surface SB4c of the region P4c and the surface SB4a of the region P4a. The surface SA4c of the region P4c is in contact with the inner surface 1a1. The heat radiation sheet 3a is compressed. Accordingly, the region P4a is pressed against the optical transmission element 2 by the elastic force E1 of the heat dissipation sheet 3a. The region P4c is pressed against the bottom wall 1b by the elastic force E4 acting in the opposite direction to the elastic force E1 of the heat dissipation sheet 3a. The heat dissipation sheet 3b has elasticity. The heat radiating sheet 3b contacts the inner surface 1b1 of the bottom wall 1b and the optical transmission element 2. The heat dissipation sheet 3b is compressed. Accordingly, the optical transmission element 2 is pressed against the region P4a by the elastic force E2 of the heat dissipation sheet 3b. The region P4a is in close contact with the optical transmission element 2 by the elastic force E1 of the heat dissipation sheet 3a and the elastic force E2 of the heat dissipation sheet 3b. The region P4c is in close contact with the bottom wall 1b by the elastic force E4 of the heat dissipation sheet 3a.

The region P4c is in close contact with the bottom wall 1b. The heat radiation sheet 3c has elasticity. The heat radiation sheet 3c contacts the circuit board 4a and the inner surface 1a1. The circuit board 4a is fixed to the bottom wall 1a. The heat radiation sheet 3c is compressed. Accordingly, the region P4c is pressed against the bottom wall 1a by the elastic force E3 of the heat dissipation sheet 3c. After all, the region P4c is in close contact with the bottom wall 1a by the elastic force E4 of the heat dissipation sheet 3a and the elastic force E3 of the heat dissipation sheet 3c.

The surface SA4a is in close contact with the optical transmission element 2 that generates heat. The surface SA4a is connected to the surface SA4b. The surface SA4b is connected to the surface SA4c. The surface SA4c is in close contact with the inner surface 1a1. Thus, the surface SA4a that is in close contact with the optical transmission element 2 and the surface SA4c that is in close contact with the inner surface 1a1 intersect in the thickness direction, in other words, in the direction in which the graphene of the graphite sheet member GF4 extends. Thermally connected. Accordingly, the heat of the optical transmission element 2 is efficiently transmitted to the bottom wall 1a and the heat sink 6 through the graphite sheet member GF4.

According to the configuration of the optical communication module 14 described above, the heat transmitting optical transmission element 2 is in contact with the region P4a, the region P4a is connected to the region P4b, the region P4b is connected to the region P4c, and the region P4c is The bottom wall 1a of the housing 1 is contacted. Therefore, the heat of the optical transmission element 2 is transmitted to the housing 1 via the graphite sheet member GF4. The surface SA4 of the graphite sheet member GF4 that comes into contact with the optical transmission element 2 is in contact with the housing 1. Therefore, the heat of the optical transmission element 2 is transmitted to the housing 1 through the one surface SA4 of the graphite sheet member GF4. The heat of the optical transmission element 2 is mainly transmitted in the surface direction of the graphite sheet member GF4, and the graphite sheet has a relatively high thermal conductivity in the surface direction. Therefore, the heat dissipation of the optical communication module 14 is improved.

Part (A) of FIG. 5 and part (B) of FIG. 5 are diagrams for schematically explaining the configuration of the optical communication module 15 according to the embodiment. 5B is a diagram schematically showing the optical communication module 15 from the light emitting part 2b side of the optical transmission element 2. FIG. The optical communication module 15 includes a housing 1, an optical transmission element 2, a heat radiation sheet 3a, a heat radiation sheet 3b, a heat radiation sheet 3c, a circuit board 4a, a circuit board 4b, and a graphite sheet member GF5. The housing 1 houses the light transmitting element 2, the heat radiating sheet 3a, the heat radiating sheet 3b, the heat radiating sheet 3c, the circuit board 4a, the circuit board 4b, the light receiving element, and the graphite sheet member GF5. The housing 1 includes a bottom wall 1a and a bottom wall 1b. On the bottom wall 1a, the heat radiating sheet 3a, the graphite sheet member GF5, the light transmitting element 2, and the heat radiating sheet 3b are sequentially arranged in the normal direction Nx of the bottom wall 1a. On the bottom wall 1a, the graphite sheet member GF5, the heat dissipation sheet 3c, the circuit board 4a, and the circuit board 4b are sequentially arranged in the normal direction Nx. The optical communication module 15 includes the optical receiving element 5 shown in FIG. The heat dissipation sheet 3c is sandwiched between the circuit board 4a and the graphite sheet member GF5. The heat dissipation sheet 3c is in contact with the circuit board 4a and the graphite sheet member GF5.

The graphite sheet member GF5 includes a region P5a (first region), a region P5b (second region), and a region P5c (third region). The region P5a includes a portion that is disposed between the bottom wall 1a and the optical transmission element 2 and that is in contact with the optical transmission element 2. The region P5a is connected to the region P5b. The region P5c is connected to the region P5b. The region P5c is in contact with the bottom wall 1a.

The region P5a includes a portion P5a1 (first portion) and a portion P5a2 (second portion). The part P5a1 includes a part P5a11 (third part), a part P5a12 (fourth part), and a part P5a13. The portion P5a11 includes a surface SA5a1 and a surface SB5a1. The portion P5a2 includes a surface SA5a2 and a surface SB5a2. The region P5b includes a surface SA5b and a surface SB5b. The region P5c includes a surface SA5c and a surface SB5c.

The part P5a1 wraps the optical transmission element 2. The portion P5a1 contacts the side surface of the optical transmission element 2. The portion P5a11 is sandwiched between the portion P5a2 and the optical transmission element 2. The part P5a11 is in contact with the part P5a2 and the optical transmission element 2. The portion P5a12 is between the optical transmission element 2 and the bottom wall 1b. The part P5a12 is in contact with the optical transmission element 2. The part P5a13 extends between the part P5a11 and the part P5a12. The part P5a13 is connected to the part P5a11 and the part P5a12. The part P5a13 is in contact with the optical transmission element 2.

The part P5a2 is in contact with the part P5a1. The part P5a2 is provided between the part P5a1 and the bottom wall 1a. The portion P5a2 is connected to the region P5b. The surface SA5a1 is in contact with the optical transmission element 2. Surface SB5a1 is in contact with surface SA5a2. The surface SA5a2 is connected to the surface SA5b. The surface SA5b is connected to the surface SA5c. Surface SB5a2 is connected to surface SB5b. The surface SB5b is connected to the surface SB5c.

The portion P5a1 includes a plurality of graphenes. The portion P5a2 includes a plurality of graphenes. The region P5b includes a plurality of graphenes. The region P5c includes a plurality of graphenes. The part P5a1 constitutes an integral graphite sheet. The portion P5a2, the region P5b, and the region P5c constitute an integral graphite sheet. In the portion P5a1, the plurality of graphenes are stacked from the surface SA5a1 side toward the surface SB5a1 side (in the thickness direction). In the integral graphite sheet including the portion P5a2, the region P5b, and the region P5c, a plurality of graphenes are stacked from the surface SA5a2 side to the surface SB5a2 side (in the thickness direction). The thickness of the portion P5a1 is the distance between the surface SA5a1 and the surface SB5a1. The thickness of the integral graphite sheet including the portion P5a2, the region P5b, and the region P5c is a distance between the surface including the surface SA5a2 and the surface including the surface SB5a2.

The surface SA5a1 is in contact with the optical transmission element 2. Surface SB5c contacts bottom wall 1a. Heat generated from the optical transmission element 2 is transmitted to the graphite sheet member GF5 through the surface SA5a1, transmitted to the bottom wall 1a through the surface SB5c, and transmitted to the heat sink 6 through the bottom wall 1a.

The graphite sheet member GF5 includes a graphite sheet (GF sheet). The graphite sheet member GF5 has, for example, heat in the X and Y directions as compared with a heat radiating gel / heat radiating sheet (corresponding to the heat radiating sheet 3a, the heat radiating sheet 3b, and the heat radiating sheet 3c), zinc die casting, aluminum, copper and the like shown in FIG. Low conductivity. The XY direction shown in FIG. 8 is a direction orthogonal to the thickness direction.

The part P5a11 and the part P5a12 are in close contact with the optical transmission element 2. The heat radiating sheet 3a, the part P5a2, the part P5a11, the optical transmission element 2, the part P5a12, the heat radiating sheet 3b, and the bottom wall 1b are sequentially provided on the inner surface 1a1 of the bottom wall 1a toward the normal direction Nx. Yes. The heat dissipation sheet 3a has elasticity. The heat dissipation sheet 3a contacts the surface SB5a2 of the portion P5a2 of the region P5a and the inner surface 1a1. The part P5a2 is in contact with the part P5a1 of the region P5a. The surface SA5a1 of the part P5a11 of the part P5a1 is in contact with the optical transmission element 2. The heat radiation sheet 3a is compressed. Therefore, the part P5a11 of the region P5a and the part P5a2 of the region P5a are brought into close contact by the elastic force E1 of the heat dissipation sheet 3a. The region P5a is pressed against the optical transmission element 2 by the elastic force E1 of the heat dissipation sheet 3a. The heat dissipation sheet 3b has elasticity. The heat dissipation sheet 3b contacts the inner surface 1b1 of the bottom wall 1b and the portion P5a12 of the portion P5a1 of the region P5a. The heat dissipation sheet 3b is compressed. Accordingly, the optical transmission element 2 is pressed against the region P5a by the elastic force E2 of the heat dissipation sheet 3b. The region P5a is in close contact with the optical transmission element 2 partially or entirely by the elastic force E1 of the heat radiating sheet 3a and the elastic force E2 of the heat radiating sheet 3b.

The region P5c is in close contact with the bottom wall 1b. The heat radiation sheet 3c has elasticity. The heat radiation sheet 3c contacts the circuit board 4a and the inner surface 1a1. The circuit board 4a is fixed to the bottom wall 1a. The heat radiation sheet 3c is compressed. Accordingly, the region P5c is pressed against the bottom wall 1a by the elastic force E3 of the heat dissipation sheet 3c. The region P5c is in close contact with the bottom wall 1a by the elastic force E3 of the heat dissipation sheet 3c.

The region P5a is in close contact with the optical transmission element 2 that generates heat. The region P5a is connected to the region P5b. The region P5b is connected to the region P5c. The region P5c is in close contact with the bottom wall 1a. Thus, the region P5a in close contact with the optical transmission element 2 and the region P5c in close contact with the inner surface 1a1 intersect in the thickness direction, in other words, in the direction in which the graphene of the graphite sheet member GF5 extends. Thermally connected. Therefore, the heat of the optical transmission element 2 is efficiently transmitted to the bottom wall 1a and the heat sink 6 through the graphite sheet member GF5.

According to the configuration of the optical communication module 15 described above, the heat transmitting optical transmission element 2 is in contact with the region P5a, the region P5a is connected to the region P5b, the region P5b is connected to the region P5c, and the region P5c is The bottom wall 1a of the housing 1 is contacted. Therefore, the heat of the optical transmission element 2 is transmitted to the housing 1 through the graphite sheet member GF5. The part P5a1 that wraps the optical transmitting element 2 and contacts the optical transmitting element 2 contacts the part P5a2, the part P5a2 connects to the region P5b, the region P5b connects to the region P5c, and the region P5c includes the casing 1 To touch. Therefore, the heat of the optical transmission element 2 is transmitted to the housing 1 through the portion P5a1, the portion P5a2, the region P5b, and the region P5c. The portion P5a1 encloses the optical transmission element 2 and comes into contact with the optical transmission element 2. Therefore, the graphite sheet can be contacted with a relatively large amount of heat generated on the surface of the optical transmission element 2. Therefore, the heat dissipation of the optical communication module 15 is improved. Therefore, the heat dissipation of the optical communication module 15 is improved.

FIG. 7 shows the correlation between the measured value of the casing temperature (Celsius) and the measured value of TEC current equivalent (Amp). Graph G1 is a measurement result of a conventional optical communication module that does not use a graphite sheet, and is as follows.
Graph G1 housing temperature (Celsius) Graph G1 TEC current equivalent (Amps)
76.86 0.419.
79.67 0.464.

A graph G2 is a measurement result of the example of the optical communication module 11, and is as follows.
Graph G2 housing temperature (Celsius) Graph G2 TEC current equivalent (Amps)
71.55 0.344.
76.14 0.401.
77.03 0.417.
78.43 0.439.
80.46 0.463.

A graph G3 is a measurement result of the example of the optical communication module 13, and is as follows.
Graph G3 enclosure temperature (Celsius) Graph G3 TEC current equivalent (Amps)
73.31 0.364.
80.83 0.455.
81.78 0.469.

A graph G4 is a measurement result of the example of the optical communication module 14, and is as follows.
Graph G4 housing temperature (Celsius) Graph G4 TEC current equivalent (Amps)
72.98 0.346.
78.69 0.415.
80.97 0.447.
82.51 0.470.

Referring to the measurement results shown in FIG. 7, the optical communication module 11, the optical communication module 13, and the optical communication module 14 using the graphite sheet member transmit light more than the conventional optical communication module that does not use the graphite sheet member. It can be seen that the heat transfer from the element to the housing (housing 1) is good. It can be seen that the configuration of the optical communication module 13 has better heat transfer from the optical transmission element 2 to the housing 1 than the configuration of the optical communication module 14. It can be seen that the configuration of the optical communication module 14 has better heat transfer from the optical transmission element 2 to the housing 1 than the configuration of the optical communication module 11.

While the principles of the invention have been illustrated and described in the preferred embodiments, it will be appreciated by those skilled in the art that the invention can be modified in arrangement and detail without departing from such principles. The present invention is not limited to the specific configuration disclosed in the present embodiment. We therefore claim all modifications and changes that come within the scope and spirit of the following claims.

DESCRIPTION OF SYMBOLS 1 ... Housing | casing, 11, 12, 13, 14, 15 ... Optical communication module, 1a, 1b ... Bottom wall, 1a1, 1b1 ... Inner surface, 2 ... Optical transmission element, 2a ... Semiconductor laser, 2b ... Light emission part, 3a, 3b, 3c ... heat dissipation sheet, 4a, 4b ... circuit board, 5 ... light receiving element, 5a ... light incident part, 6 ... heat sink, E1, E2, E3, E4 ... elastic force, GF1, GF2, GF3, GF4 , GF5 ... graphite sheet member, H1, H2 ... through hole, Nx ... normal direction, P1a (first region), P1b (second region), P1c (third region), P2a (first region) ), P2b (second region), P2c (third region), P3a (first region), P3b (second region), P3c (third region), P4a (first region), P4b (second region), P4c (third region), P5a (first region) ), P5b (second region), P5c (third region)... Region, P2a1 (first portion), P2a2 (second portion), P3b1 (second portion), P3b2 (first portion) ), P5a1 (first part), P5a11 (third part), P5a12 (fourth part), P5a13, P5a2 (second part)... Part, SA1a, SA1b, SA1c, SA2a1, SA2a2, SA2b, SA2c, SA3a (first surface), SA3b1, SA3b2 (second surface), SA3c, SA4, SA4a, SA4b, SA4c, SA5a1, SA5a2, SA5b, SA5c, SB1a, SB1b, SB1c, SB2a1, SB2a2, SB2b, SB2c, SB3a, SB3b1 (third surface), SB3b2, SB3c (fourth surface), SB4a, SB4b, S 4c, SB5a1, SB5a2, SB5b, SB5c ... surface.

Claims (5)

A housing,
An optical transmission element;
A graphite sheet member;
With
The housing includes a bottom wall;
The housing houses the optical transmission element, the graphite sheet member, and a circuit board,
The graphite sheet member comprises a first region, a second region, and a third region,
The first region includes a portion disposed between the bottom wall and the optical transmission element and in contact with the optical transmission element, and is connected to the second region,
The third region is connected to the second region and contacts the bottom wall;
An optical communication module. The first region consists of a first part and a second part,
The first part and the second part are sequentially arranged from the optical transmission element toward the bottom wall,
The first part is sandwiched between the optical transmission element and the second part, and is in contact with the optical transmission element and the second part,
The second portion connects to the second region;
The optical communication module according to claim 1. The second region consists of a first part and a second part,
The first portion is connected to the first region;
The second portion is connected to the third region;
The first part and the second part are in contact with each other;
The first region comprises a first surface;
The first portion comprises a second surface;
The second portion comprises a third surface;
The third region comprises a fourth surface;
The first surface is in contact with the optical transmission element;
The second surface is connected to the first surface;
The second surface is in contact with the third surface;
The third surface is connected to the fourth surface;
The fourth surface contacts the bottom wall;
The optical communication module according to claim 1. The graphite sheet member comprises a surface,
The graphite sheet member is bent between the optical transmission element and the bottom wall so that the surface is in contact with the optical transmission element and the bottom wall.
The optical communication module according to claim 1. The first region consists of a first part and a second part,
The first portion encloses the optical transmission element and contacts a side surface of the optical transmission element;
The second part is in contact with the first part, provided between the first part and the bottom wall, and connected to the second region;
The first part includes a third part and a fourth part,
The third part is sandwiched between the second part and the optical transmission element, and is in contact with the second part and the optical transmission element.
The fourth part is on the opposite side of the third part and contacts the optical transmission element;
The optical communication module according to claim 1.