JP2013093775A - Optical communication device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical communication device capable of preventing intrusion of dust or the like by blocking the inside of a casing.SOLUTION: A circuit board 2 with a light guide 3 embedded therein is sandwiched and fixed between the bottom 11 and the lid 12a of a casing 1. An optical communication module 5 mounted on the circuit board 2 is capable of transmission and reception of an optical signal via the light guide 3. The constitution of sandwiching and fixing the circuit board 2 between the bottom 11 and the lid 12 facilitates blocking the inside of the casing 1, which prevents the intrusion of dust or the like into the inside from a place of the casing 1 for exposing the circuit board 2 therefrom. Furthermore, on the surfaces of the circuit board 2, GND wiring patterns 22 are provided at portions which are brought into contact with the casing 1 when sandwiched between the bottom 11 and the lid 12, which suppresses leakage of noise to the outside of the casing 1.

Description

  The present invention relates to an optical communication apparatus that performs optical communication using a photoelectric conversion element such as a laser diode and / or a photodiode.

  Conventionally, optical communication using an optical fiber or the like has been widely used. In optical communication, electrical signals are converted into optical signals by photoelectric conversion elements such as laser diodes, optical signals are transmitted and received via optical fibers, and received optical signals are converted into electrical signals by photoelectric conversion elements such as photodiodes. Is done by doing. For this reason, an optical communication module in which a photoelectric conversion element such as a laser diode and / or a photodiode is configured as one package together with a peripheral circuit element for operating the photoelectric conversion element in some cases is widely used. This optical communication module is called OSA (Optical Sub-Assembly). In recent years, various inventions related to optical communication devices and optical communication modules have been made.

  For example, in Patent Document 1, a photoelectric element that transmits or receives an optical signal, a stem for fixing the photoelectric element, a cap for covering the photoelectric element, an electric signal applied to the photoelectric element, or from the photoelectric element A plurality of leads for transmitting electrical signals, and a plane portion is provided at one end of a predetermined lead located in a package constituted by a stem and a cap, and one end is connected to the photoelectric element on the plane portion. There has been proposed an optical-electrical conversion module that is excellent in high-frequency characteristics and can be miniaturized by providing an electric circuit component whose end is connected to a lead.

JP 2005-167189 A

  The optical communication module is connected to a circuit board or the like of the optical communication apparatus, and is housed in the casing of the optical communication apparatus together with the circuit board. Since an optical communication line such as an optical fiber needs to be connected to the optical communication module, a passage hole for allowing the optical communication line to pass through and connecting to the internal optical communication module is formed in the optical communication device housing Is done. When a hole communicating between the inside and the outside is formed in the housing of the optical communication apparatus, there arises a problem that dust from the outside of the housing enters the inside. In order to prevent this, a member for closing the passage hole formed in the housing is necessary, which increases the cost of the optical communication device.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide an optical communication apparatus capable of blocking the inside of a housing and preventing entry of dust and the like.

  An optical communication device according to the present invention includes a photoelectric conversion element that performs conversion from an optical signal to an electrical signal or an electrical signal to an optical signal, an optical communication module that includes a housing that houses the photoelectric conversion element, and the optical communication module. In an optical communication device comprising a circuit board on which a communication module is mounted and a housing for housing the optical communication module and the circuit board, one side surface of the circuit board and the mounted light are embedded in the circuit board A light guide unit configured to guide an optical signal between the communication modules, wherein the housing includes a plurality of housing components, and a plurality of the housing components in a state where one side surface of the circuit board is exposed to the outside; And a board holding portion for holding the circuit board.

  In the optical communication device according to the present invention, a hole is formed in the circuit board, and the optical communication module protrudes from the housing and is fixed by being inserted into the hole. And a means for guiding an optical signal between one side portion of the columnar portion and the photoelectric conversion element accommodated in the container, and the light guide portion is provided on the circuit board. It is provided so that an optical signal may be guide | induced between one side surface and the inner surface of the said hole.

  Further, in the optical communication device according to the present invention, a concave portion that accommodates an end portion of the optical communication line is provided on one side surface of the circuit board, and the light guide portion of the optical communication line accommodated in the concave portion is provided. It is provided so that an optical signal may be guided between a part facing the end part and the optical communication module mounted on the circuit board.

  In the optical communication device according to the present invention, a wiring pattern connected to a fixed potential is provided on a surface of the circuit board at a portion that comes into contact with the housing when the circuit board is held by the board holding portion. It is characterized by that.

In the present invention, a light guide part for guiding an optical signal is provided in the circuit board by embedding an optical fiber or the like in the circuit board on which the optical communication module is mounted. One end of the light guide is exposed on one side of the circuit board, and the other end is exposed at a position facing the light receiving unit or the light emitting unit when the optical communication module is mounted. An optical signal is guided to and from the optical communication module.
Moreover, the housing | casing of an optical communication apparatus is comprised by several housing components, such as a bottom and a cover, for example. The circuit board is fixed by being sandwiched by a plurality of casing components such that one side surface provided with one end of the light guide is exposed outside the casing.
As a result, the optical communication module mounted on the circuit board can transmit and receive optical signals to and from the outside of the housing via the light guide in the circuit board. It is not necessary to form a hole for inserting the wire. Further, since the plurality of housing parts are sandwiched between the circuit boards, the inside of the housing can be closed, and dust and the like can be prevented from entering inside from a portion of the circuit board where a part of the circuit board is exposed.

  Further, in the present invention, the optical communication module has a columnar portion protruding from a housing in which the photoelectric conversion element is accommodated, and a means for guiding an optical signal between one side portion of the columnar portion and the photoelectric conversion element in the housing. Is provided in the columnar part. Further, a hole for inserting and fixing the columnar portion of the optical communication module is formed in the circuit board. The light guide in the circuit board has one end exposed on one side of the circuit board and the other end exposed on the inner surface of the hole of the circuit board, so that light is transmitted between one side of the circuit board and the inner surface of the hole. The optical signal is guided between one side surface of the circuit board and the optical communication module fixed by being inserted into the hole. Thereby, mounting of the optical communication module on the circuit board can be facilitated.

  In the present invention, a concave portion for accommodating an end portion of an optical communication line such as an optical fiber is provided on one side surface of the circuit board exposed from the casing. Thereby, the connection of the optical communication line with respect to the optical communication apparatus can be facilitated. The light guide in the circuit board has one end exposed at a portion facing the end of the optical communication line accommodated in the recess, and the other end becomes a light receiving unit or light emitting unit when the optical communication module is mounted. By exposing to the opposite location, an optical signal is guided between the optical communication line accommodated in the recess and the optical communication module.

  In the present invention, on the surface of the circuit board, a wiring pattern connected to a fixed potential (for example, a ground potential or a power supply potential) is provided in a portion that is sandwiched and contacted by the casing components. Thereby, it can suppress that the noise which generate | occur | produces with operation | movement of the electric circuit mounted in the circuit board leaks out of a housing | casing.

  In the case of the present invention, the light guide is embedded in the circuit board to guide the optical signal between the one side surface of the circuit board and the optical communication module, and the one side surface of the circuit board is exposed to the outside. In addition, since the circuit board is sandwiched by a plurality of housing parts, it is not necessary to form a hole for inserting the optical communication line in the housing of the optical communication device. Intrusion of dust and the like can be prevented.

It is typical sectional drawing which shows the structure of the optical communication apparatus which concerns on this invention. It is a typical exploded perspective view showing the composition of a part of a case and a circuit board. It is typical sectional drawing which shows the structure of a circuit board and an optical communication module. FIG. 10 is a schematic perspective view illustrating a configuration of a circuit board of an optical communication device according to Modification 1. FIG. 10 is a schematic cross-sectional view illustrating a configuration of a circuit board and an optical communication module of an optical communication device according to Modification 2.

  Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof. FIG. 1 is a schematic cross-sectional view showing a configuration of an optical communication apparatus according to the present invention. In the figure, reference numeral 1 denotes a housing of the optical communication apparatus, and a part of a wall constituting the housing 1 is shown as a cross section. In the housing 1 of the optical communication apparatus, an optical communication module 5 for transmitting and receiving an optical signal via an optical communication line (not shown) such as an optical fiber, and various types including the optical communication module 5 are provided. A circuit board 2 on which circuit elements are mounted is accommodated. The casing 1 is manufactured by being divided into at least two parts, that is, a bottom part 11 and a lid part 12, and the casing 1 is configured by assembling these parts. The circuit board 2 is fixed by being sandwiched between the bottom portion 11 and the lid portion 12 when the housing 1 is assembled.

  FIG. 2 is a schematic exploded perspective view showing a partial configuration of the housing 1 and the circuit board 2. The circuit board 2 has a configuration in which a substantially rectangular extending portion 2a having a tongue shape is provided on one side surface of a substantially rectangular plate. The circuit board 2 includes an optical communication module 5 and various circuit components (not shown) such as an IC (Integrated Circuit), a resistor, and a capacitor, and constitutes an electric circuit related to communication processing of the optical communication device. Is done.

  The bottom portion 11 of the housing 1 has a bowl-like shape surrounding a bottom surface (not shown), and a recess 11a is formed at a part of the upper end of the peripheral wall. The depth of the recess 11a is about half of the thickness of the circuit board 2, and the length (the length in the circumferential direction of the peripheral wall) is the width of the extending portion 2a of the circuit board 2 (perpendicular to the extending direction). Is substantially the same as the length in the direction to be Similarly, the lid portion 12 of the housing 1 has a configuration in which a peripheral wall is provided downward surrounding a top surface (not shown), and a recess 12a is formed at a part of the lower end of the peripheral wall. The depth of the recess 12 a is approximately half the thickness of the circuit board 2, and the length thereof is substantially the same as the width of the extended portion 2 a of the circuit board 2. That is, the shapes of the recesses 11a and 12a are substantially the same.

  The housing 1 is configured by fixing the bottom 11 and the lid 12 so that the recesses 11a and 12a face each other. The bottom 11 and the lid 12 can be fixed by various methods such as adhesion, welding, or screwing. The circuit board 2 is sandwiched and fixed between the bottom portion 11 and the lid portion 12 so that the extended portion 2a is accommodated in the concave portions 11a and 12a. At this time, the circuit board 2 may be bonded to the bottom 11 and the lid 12 using an adhesive or the like. In a state where the circuit board 2 is sandwiched and fixed between the bottom part 11 and the lid part 12, the recesses 11a and 12a are closed by the circuit board 2, so that the inside and outside of the housing 1 do not communicate with each other through the recesses 11a and 12a. It is.

  On the upper and lower surfaces of the circuit board 2, wiring patterns are provided in contact portions of the extended portions 2 a with the housing 1. This wiring pattern is a so-called GND wiring pattern 22 that is connected to the ground potential when the optical communication apparatus is powered on.

  A light guide 3 for guiding an optical signal is embedded in the circuit board 2. The light guide 3 is provided in such a manner that a round linear light guide member such as an optical fiber is embedded in the circuit board 2, and one end thereof is a side surface of the extension part 2 a of the circuit board 2 (the extension part 2 a of the extension part 2 a). It is exposed at the end face in the extending direction). Further, a substantially circular through hole 21 penetrating vertically is formed at an appropriate place on the circuit board 2, and the other end of the light guide portion 3 is exposed on the inner surface of the through hole 21. That is, the light guide 3 is provided so as to guide an optical signal between one side surface of the circuit board 2 and the inner surface of the through hole 21.

  FIG. 3 is a schematic cross-sectional view showing configurations of the circuit board 2 and the optical communication module 5. The optical communication module 5 includes a bottomed rectangular tube-shaped housing portion 51 in which the photoelectric conversion element 6 is housed, a lid portion 52 that closes the upper opening of the housing portion 51, and a bottom surface of the housing portion 51. It is the structure which has the columnar part 53 provided. The accommodating portion 51 has a substantially square shape in plan view, and a substantially circular through hole 51a is formed in the approximate center of the bottom surface. In addition, a metal frame 54 is fixed to the bottom of the accommodating portion 51, and a substantially circular through hole 54 a is formed in the frame 54 in accordance with the through hole 51 a of the accommodating portion 51. A part of the frame 54 is exposed to the outside from the side surface of the accommodating portion 51, and is used as a connection terminal for connection to a wiring pattern provided on the circuit board 2.

  The photoelectric conversion element 6 is an element that converts an optical signal and an electric signal. The photoelectric conversion element 6 has a substantially rectangular parallelepiped main body 61 in plan view, and light provided in the approximate center of the lower surface of the main body 61. A signal light receiving unit or light emitting unit (not shown) and one or a plurality of terminal units 62 provided around the light receiving unit or light emitting unit are provided. The photoelectric conversion element 6 is fixed by connecting the terminal portion 62 to the periphery of the through hole 54a of the frame 54 by a method such as soldering. Thereby, the photoelectric conversion element 6 can transmit and receive an optical signal through the through hole 51 a of the housing portion 51 and the through hole 54 a of the frame 54.

  The columnar portion 53 of the optical communication module 5 has a cylindrical shape and is provided so as to protrude downward from the lower surface of the housing portion 51. The diameter of the columnar portion 53 is substantially equal to the diameter of the through hole 21 of the circuit board 2, and the length is substantially the same as the thickness of the circuit board 2 or longer than the thickness of the circuit board 2. The optical communication module 5 inserts the columnar portion 53 into the through hole 21 of the circuit board 2 and connects the frame 54 exposed to the outside from the housing portion 51 to the circuit board 2 by soldering or the like as a connection terminal. Mounted on the substrate 2.

  An optical signal light guide portion 55 is provided in the columnar portion 53 by embedding an optical member such as translucent synthetic resin or glass. The light guide portion 55 is provided such that one end is exposed at the upper portion of the columnar portion so as to face the through hole 51 a of the accommodating portion 51, and the other end is provided so as to be exposed at a part of the side surface of the columnar portion 53. It is provided in such a manner that it bends substantially vertically in the columnar portion 53. When the columnar part 53 is inserted into the through hole 21 of the circuit board 2 and the optical communication module 5 is mounted on the circuit board 2, it matches the exposed position of the light guide part 3 embedded in the circuit board 2 in the through hole 21. Thus, the exposure position of the light guide portion 55 on the side surface of the columnar portion 53 is determined. The light guide portion 55 is formed with an inclined plane inclined at approximately 45 ° with respect to the axial direction of the columnar portion 53 at a bent portion in the columnar portion 53, and this inclined plane serves as a reflection surface 55a of the optical signal. Works.

  Thereby, in a state where the optical communication module 5 is mounted on the circuit board 2, for example, when the photoelectric conversion element 6 is a light emitting element, the optical signal emitted from the light emitting unit provided on the lower surface of the photoelectric conversion element 6 is transmitted to the frame 54. Through the through hole 54a and the through hole 51a of the accommodating portion 51 and enters the light guide portion 55 exposed at the upper portion of the columnar portion 53, and is reflected substantially vertically by the reflecting surface 55a in the light guide portion 55 in the lateral direction. The light is emitted from the exposed portion of the light guide portion 55 on the side surface of the columnar portion 53. The optical signal emitted from the light guide unit 55 enters the light guide unit 3 exposed in the through hole 21 of the circuit board 2, passes through the light guide unit 3 in the circuit board 2, and extends from the circuit board 2. The light is emitted from the exposed portion of the light guide 3 on the side surface 2a. The optical signal emitted from the light guide 3 is received by another optical communication device via an optical communication line connected to the extended portion 2a of the circuit board 2 via a connector or the like, for example.

  For example, when the photoelectric conversion element 6 is a light receiving element, an optical signal transmitted from another optical communication device is incident on the light guide 3 exposed on the side surface of the extension portion 2a of the circuit board 2 via the optical communication line. Then, the light passes through the light guide 3 in the circuit board 2 and exits from the exposed portion of the light guide 3 in the through hole 21 of the circuit board 2. The optical signal emitted from the light guide unit 3 is incident on the light guide unit 55 exposed on the side surface of the columnar unit 53 of the optical communication module 5 inserted into the through hole 21, and is reflected by the reflection surface 55 a in the light guide unit 55. Reflected upward in a substantially vertical direction, emitted from the exposed portion of the light guide portion 55 above the columnar portion 53, and provided on the lower surface of the photoelectric conversion element 6 through the through hole 51 a of the housing portion 51 and the through hole 54 a of the frame 54. The received light is received by the received light receiving unit.

  The optical communication apparatus having the above configuration is mounted on the circuit board 2 by adopting a configuration in which the circuit board 2 in which the light guide unit 3 is embedded is sandwiched and fixed between the bottom part 11 and the cover part 12 of the housing 1. Since the optical communication module 5 can transmit and receive optical signals through the light guide portion 3, it is not necessary to form a hole for inserting an optical communication line in the housing 1 of the optical communication device. In addition, since the circuit board 2 is sandwiched and fixed between the bottom part 11 and the cover part 12, the inside of the housing 1 can be easily closed, and dust or the like can be seen from the portion of the housing 1 where the circuit board 2 is exposed. Can be prevented from entering the inside.

  In the optical communication module 5, a columnar portion 53 protrudes from the lower surface of the accommodating portion 51 that accommodates the photoelectric conversion element 6, and an optical signal is guided between one side portion of the columnar portion 53 and the photoelectric conversion element 6. The light guide part 55 is provided in the columnar part 53. Further, a through hole 21 for inserting and fixing the columnar portion 53 is formed in the circuit board 2, and one end of the light guide portion 3 in the circuit board 2 is exposed to the side surface of the extending portion 2 a of the circuit board 2. Then, the other end is exposed to the inner surface of the through hole 21 of the circuit board 2 to guide the optical signal between one side surface of the circuit board 2 and the inner surface of the through hole 21. Thereby, an optical signal can be exchanged between one side surface of the circuit board 2 and the photoelectric conversion element 6 of the optical communication module 5 inserted and fixed in the through hole 21, and the circuit board of the optical communication module 5. 2 can be facilitated.

  Further, a GND wiring pattern 22 is provided on the surface (upper and lower surfaces) of the circuit board 2 at a portion sandwiched between and contacted with the bottom portion 11 and the lid portion 12, thereby accompanying the operation of the electric circuit mounted on the circuit substrate 2. Can be prevented from leaking to the outside of the housing 1.

  In addition, in this Embodiment, the shape etc. of the circuit board 2 and the optical communication module 5 which were shown in FIGS. 1-3 are examples, Comprising: It does not restrict to this. Moreover, although the optical communication module 5 was set as the structure which has any one of a light emitting element or a light receiving element as the photoelectric conversion element 6, it is not restricted to this, The structure which has both may be sufficient. Moreover, although it was set as the structure provided with the one light guide part 3 in the circuit board 2, it is not restricted to this, A plurality of light guide parts 3 are provided in the circuit board 2, and the some through-hole 21 is formed, and several The optical communication module 5 may be configured to be mountable.

(Modification 1)
FIG. 4 is a schematic perspective view showing the configuration of the circuit board 102 of the optical communication apparatus according to the first modification. In the circuit board 102 according to the first modification, a recessed portion 102b is formed in an extended portion 102a provided on one side surface. The concave portion 102b is formed across the extended end surface and the upper surface of the extended portion 102a. The bottom surface of the concave portion 102b is substantially rectangular in the extending direction of the extended portion 102a, and the inner surface parallel to the extended end surface is formed. It is a substantially rectangular parallelepiped recess that forms a substantially square shape. An end portion of the light guide unit 3 embedded in the circuit board 102 is exposed at a substantially center of the back surface of the recess 102b. The vertical and horizontal widths of the back surface of the recess 102b are substantially the same as or larger than the diameter of the optical communication line (not shown) connected to the optical communication device. The tip of the communication line can be accommodated.

  The optical communication apparatus according to the first modification having the above configuration is easy to connect the optical communication line to the optical communication apparatus by providing the extended portion 102a of the circuit board 102 with the recess 102b that accommodates the end of the optical communication line. Can be For example, after the end of the optical communication line is accommodated in the recess 102b, the optical communication line can be connected by a method such as bonding the optical communication device to the circuit board 102 with an adhesive or the like.

(Modification 2)
FIG. 5 is a schematic cross-sectional view illustrating configurations of the circuit board 202 and the optical communication module 205 of the optical communication apparatus according to the second modification. The optical communication module 205 of Modification 2 has a configuration in which the optical communication module 5 illustrated in FIGS. 1 and 3 does not include the columnar portion 53. That is, the optical communication module 205 of Modification 2 includes the housing part 51, the lid part 52, the frame 54, and the photoelectric conversion element 6, and is formed on the lower surface of the housing part 51 without the columnar part 53 and the light guide part 55. In this configuration, optical signals are transmitted / received to / from the outside through the through-hole 51a.

  Further, the circuit board 202 according to the modification 2 is not formed with the through hole 21 for inserting and fixing the columnar portion 53 of the optical communication module 5. One end of the light guide unit 203 embedded in the circuit board 202 is exposed at an extended portion (not shown in FIG. 5) of the circuit board 202, and the other end is exposed on the upper surface of the circuit board 202. For this reason, the light guide 203 is provided with a reflecting surface 203a that reflects the optical signal substantially vertically.

  The optical communication module 205 is exposed to the outside from the housing portion 51 in a state where the through hole 51a formed in the lower surface of the housing portion 51 is aligned with the light guide portion 203 exposed on the upper surface of the circuit board 202. It is mounted on the circuit board 202 by being connected to the circuit board 202 by soldering or the like using the frame 54 as a connection terminal.

  For example, when the photoelectric conversion element 6 is a light emitting element, an optical signal emitted from a light emitting portion provided on the lower surface of the photoelectric conversion element 6 is transmitted through the through hole 54 a of the frame 54 and the through hole 51 a of the housing portion 51. The light enters the light guide unit 203, is reflected substantially vertically by the reflection surface 203 a in the light guide unit 203, and exits from the exposed portion of the light guide unit 203 on the side surface of the extended portion of the circuit board 202.

  For example, when the photoelectric conversion element 6 is a light receiving element, an optical signal transmitted from another optical communication device is incident on the light guide unit 203 exposed on the side surface of the extension portion of the circuit board 2 through the optical communication line. The light receiving portion provided on the lower surface of the photoelectric conversion element 6 is reflected substantially vertically upward by the reflecting surface 203a in the light guide portion 203 and passes through the through hole 51a of the housing portion 51 and the through hole 54a of the frame 54. Received light.

  The optical communication module provided in the optical communication apparatus according to the present invention is not limited to the optical communication module 5 shown in FIG. 3 or the optical communication module 205 shown in FIG. 5, but may have other shapes and configurations. The mounting method on the circuit board 2 and the structure of the light guide section in the circuit board 2 can be appropriately determined according to the module configuration.

DESCRIPTION OF SYMBOLS 1 Case 2 Circuit board 2a Extension part 3 Light guide part 5 Optical communication module 6 Photoelectric conversion element 11 Bottom part (case part)
11a Concave part (substrate clamping part)
12 Lid (casing parts)
12a Concave part (substrate clamping part)
21 Through hole (hole)
22 GND wiring pattern (wiring pattern)
51 container (container)
51a Through-hole 52 Lid part 53 Column-shaped part 54 Frame 54a Through-hole 55 Light guide part (means to guide)
55a Reflective surface 61 Body portion 62 Terminal portion 102 Circuit board 102a Extending portion 102b Recessed portion 202 Circuit board 203 Light guide portion 203a Reflective surface 205 Optical communication module

Claims (4)

A photoelectric conversion element that performs conversion from an optical signal to an electrical signal or an electrical signal to an optical signal, an optical communication module having a housing that houses the photoelectric conversion element, and a circuit board on which the optical communication module is mounted In an optical communication device comprising a housing for housing the optical communication module and the circuit board,
Embedded in the circuit board, comprising a light guide section for guiding an optical signal between one side surface of the circuit board and the mounted optical communication module;
The housing is
Consists of multiple housing parts,
An optical communication apparatus, comprising: a board holding portion that holds the circuit board between the plurality of casing parts in a state where one side surface of the circuit board is exposed to the outside. A hole is formed in the circuit board,
The optical communication module is:
A columnar portion that protrudes from the container and is fixed by being inserted into the hole;
A means for guiding an optical signal between the one side part of the columnar part and the photoelectric conversion element accommodated in the container;
The optical communication device according to claim 1, wherein the light guide unit is provided to guide an optical signal between one side surface of the circuit board and an inner surface of the hole. One side surface of the circuit board is provided with a recess that accommodates an end of the optical communication line,
The light guide section is provided so as to guide an optical signal between a portion facing an end of an optical communication line housed in the recess and the optical communication module mounted on the circuit board. The optical communication device according to claim 1 or 2. The wiring pattern connected to a fixed potential is provided on the surface of the circuit board at a portion that comes into contact with the housing when the circuit board is held by the board holding portion. 4. The optical communication device according to any one of 3.

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