JP2005243800A - Optical transmission module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical transmission module capable of being readily miniaturized and being easily heat-radiated. <P>SOLUTION: In the optical transmission module 1, a plurality of optical transmitting circuit boards 2 with heating electronic components 5 and light-emitting elements 6, 7, 8, 9 or a light-receiving element mounted thereon are juxtaposed at a predetermined distance, and the optical transmission circuit boards 2 are attached to a main circuit board 3 housed in a casing 4. The casing 4 is provided with a heat conduction projection 13 which abuts against the electronic components 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical transmission module in which a plurality of optical transmission circuit boards are arranged in parallel at predetermined intervals.

  In order to transmit / receive more information, there is a technique for transmitting and receiving a plurality of laser beams having different wavelengths. In this technique, as shown in FIG. 4, a wavelength division multiplexing optical transmission module 30 that multiplexes and transmits a plurality of laser beams having different wavelengths and is connected to the wavelength division multiplexing optical transmission module 30 via an optical fiber 31 and transmitted. The optical signal is transmitted / received to / from the wavelength-multiplexed light receiving module 32 that demultiplexes and receives the laser light for each wavelength.

  As shown in FIG. 5, the wavelength division multiplexing optical transmission module 30 is connected to four light emitting elements 6, 7, 8, 9 that oscillate laser beams having different wavelengths, and these light emitting elements 6, 7, 8, 9 The circuit board 33 and an optical multiplexer 34 that combines the laser beams emitted from the respective light emitting elements 6, 7, 8, and 9 are configured.

  A technique described in Patent Document 1 is known as a technique for downsizing an optical transmission module such as the wavelength division multiplexing optical transmission module 30. As shown in FIG. 6, the optical transmission module 35 is configured to arrange optical transmission circuit boards 38 and 39 on which the light emitting element 36 or the light receiving element 37 is mounted in parallel with a predetermined interval therebetween. Thereby, in the wavelength division multiplexing optical transmission module 30 described above, a plurality of light emitting elements or light receiving elements attached along one side of the circuit board 33 are divided into separate circuit boards 38 and 39 to reduce the size.

JP 2001-296457 A

  However, since the optical transmission circuit boards 38 and 39 mounted with the heat generating electronic component 40 are arranged in parallel, there is a problem that heat radiation is difficult.

  Accordingly, an object of the present invention is to provide an optical transmission module that can be easily downsized and easily radiated.

  In order to achieve the above object, the present invention provides a plurality of optical transmission circuit boards on which a heat generating electronic component is mounted and a light emitting element or a light receiving element is mounted in parallel at a predetermined interval. An optical transmission module in which a substrate is attached to a main circuit board and accommodated in a casing, wherein the casing is provided with a heat transfer protrusion to be brought into contact with the electronic component.

  And it is good to interpose the heat-transfer material which can deform | transform between the said electronic component and the said heat transfer protrusion.

  The heat transfer protrusion may be formed in a plate shape that partitions the casing along the optical transmission circuit board.

  Also, a plurality of optical transmission circuit boards on which a heat generating electronic component is mounted and a light emitting element or a light receiving element are mounted are arranged in parallel at predetermined intervals, and the optical transmission circuit boards are attached to the main circuit board. An optical transmission module accommodated therein, wherein a slit for inserting the optical transmission circuit board is formed in the casing, and the optical transmission circuit board is projected from the slit.

  A heat transfer material may be interposed between the casing and the optical transmission circuit board.

  The optical transmission circuit board may have a metal surface at a protruding portion protruding from the slit.

  The optical transmission circuit board may protrude from the slit over the entire length of one side.

  According to the present invention, the optical transmission module can be easily downsized and easily radiated.

  FIG. 1 is a front sectional view of a wavelength division multiplexing optical transmission module showing a preferred embodiment of the present invention, and FIG. 2 is a schematic perspective view showing an internal structure of the wavelength division multiplexing optical transmission module.

  As shown in FIGS. 1 and 2, a wavelength division multiplexing optical transmission module 1 includes a plurality of optical transmission circuit boards 2 arranged in parallel at a predetermined interval, and a main circuit board for fixing the optical transmission circuit boards 2. 3 and a casing 4 for housing the main circuit board 3 together with the optical transmission circuit board 2.

  The optical transmission circuit board 2 is mounted with a heat generating electronic component 5 and light emitting elements 6, 7, 8, and 9, and is formed in a strip shape. The electronic component 5 that generates heat is specifically a driver IC or the like that drives the light-emitting elements 6, 7, 8, and 9, and the light-emitting elements 6, 7, 8, and 9 each emit laser light having a different wavelength. LD). The optical transmission circuit board 2 is fixed on one side to the main circuit board 3 via the pin-shaped leads 10 and is electrically connected. A plurality of leads 10 are provided on one side of the optical transmission circuit board 2 so as to extend in the direction along the substrate surface 11, and the optical transmission circuit board 2 is mounted upright on the main circuit board 3. Yes.

  The main circuit board 3 has a clock data recovery (CDR) function, and is configured to reproduce the waveform of an electrical signal sent from a mother board (not shown) and send it to each circuit board 2 for optical transmission. The main circuit board 3 and the optical transmission circuit board 2 are connected via leads 10. Specifically, the lead 10 is inserted upright in an insertion hole 12 formed in the circuit board 2 for optical transmission, and solder is applied to a printed circuit (not shown) exposed to the insertion hole 12. Connected through.

  The casing 4 is formed of a metal in a rectangular box shape, and has a heat transfer protrusion 13 that comes into contact with the electronic component 5 mounted on the optical transmission circuit board 2.

  The heat transfer protrusion 13 is formed of the same metal as the casing 4 and is formed in a plate shape extending on the top plate portion 14 of the casing 4 toward the main circuit board 3 side. That is, the heat transfer protrusion 13 extends substantially vertically from the top plate portion 14 that covers the substrate surface 15 of the main circuit board 3. A plurality of heat transfer protrusions 13 are arranged in parallel so that each electronic component 5 is sandwiched between the optical transmission circuit board 2 and the main circuit board 3 together with the optical transmission circuit board 2 in the casing 4. Is arranged.

  Further, a deformable heat transfer material 16 is interposed between the heat transfer protrusion 13 and the electronic component 5. The heat transfer material 16 is made of a heat conductive sheet, heat conductive grease, or the like, and absorbs and deforms the inclination of the optical transmission circuit board 2 or the manufacturing error of the casing 4 to deform the optical transmission circuit board 2 and the heat transfer material 16. A heat transfer path is secured between the protrusions 13.

  In particular, the heat transfer protrusion 13 is formed so as to partition the inside of the casing 4 along the optical transmission circuit board 2 and is configured to shield between the electronic components 5.

  Next, the operation of this embodiment will be described.

  When assembling the wavelength division multiplexing optical transmission module 1, first, the light emitting elements 6, 7, 8 and 9 are aligned and fixed to a multiplexer (not shown), and the optical transmission circuit board 2 is attached to the main circuit board 3 respectively. Install. At this time, since the optical transmission circuit board 2 is fixed to the main circuit board 3 by inserting the pin-like leads 10 into the insertion holes 12 of the main circuit board 3, the alignment of the light emitting elements 6, 7, 8, 9 is performed. Even if it is slightly tilted or misaligned, it can be attached to the main circuit board 3 as it is.

  When each optical transmission circuit board 2 is attached to the main circuit board 3, a heat transfer material 16 is attached to each electronic component 5 mounted on the optical transmission circuit board 2, and the main circuit board 3 is attached to the optical transmission board. The circuit board 2 is accommodated in the casing 4. Accordingly, the electronic components 5 are brought into contact with the heat transfer protrusions 13 of the casing 4 directly or via the heat transfer material 16. At this time, the optical transmission circuit board 2 may be inclined or misaligned, but the heat transfer material 16 is deformed to fill the gap between the electronic component 5 and the heat transfer protrusion 13, so that the optical transmission circuit A large heat transfer path corresponding to the size of the electronic component 5 can be secured while absorbing the inclination and positional deviation of the substrate 2.

  When the wavelength division multiplexing optical transmission module 1 is operated, the heat generated from the electronic component 5 is transmitted to the heat transfer protrusion 13 directly or via the heat transfer material 16 and is transmitted to the top plate portion 14 of the casing 4. Since the heat transfer material 16 is in close contact with the electronic component 5 and the heat transfer protrusion 13 in a wide area, the electronic component 5 does not accumulate heat and is transferred to the heat transfer protrusion 13 satisfactorily. The heat transmitted to the top plate portion 14 is efficiently radiated to the outside while being transmitted to the entire casing 4.

  As described above, since the heat transfer protrusion 13 to be brought into contact with the electronic component 5 is provided on the casing 4, a plurality of circuit boards 2 for optical transmission are arranged in parallel to reduce the size of the wavelength division multiplexing optical transmission module 1. The heat dissipation can be improved. Further, since the optical transmission circuit board 2 is attached to the main circuit board 3, the circuit can be formed separately into the optical transmission circuit board 2 and the main circuit board 3, and the wavelength division multiplexing optical transmission module 1 is further reduced in size. Can be

  In addition, since the deformable heat transfer material 16 is interposed between the electronic component 5 and the heat transfer protrusion 13, it is possible to prevent the electronic component 5 and the heat transfer protrusion 13 from being biased in a small area. A large heat transfer path corresponding to the size of the electronic component 5 can be secured between the electronic component 5 and the heat transfer protrusion 13.

  Since the heat transfer protrusions 13 are formed in a plate shape that partitions the casing 4 along the circuit board 2 for light transmission, the electronic components 5 can be easily shielded with a simple structure, such as crosstalk. Can be prevented.

  In addition, although the wavelength multiplexing optical transmission module 1 on the transmission side has been described, a wavelength multiplexing optical transmission module (not shown) on the reception side may be used. In this case, instead of the optical transmission circuit board 2 on which the light emitting elements 6, 7, 8, 9 are mounted, an optical transmission circuit board (not shown) on which the light receiving element (not shown) is mounted is used as the main circuit board 3. It is good to attach.

  The casing 4 is made of metal, but may be formed of other materials having heat transfer properties and shielding properties.

  Another embodiment will be described. However, the description of the same configuration as described above is omitted, and the same reference numerals are given.

  FIG. 3 is a front cross-sectional view of a wavelength division multiplexing optical transmission module showing another embodiment of the present invention.

  As shown in FIG. 3, the wavelength division multiplexing optical transmission module 20 includes a plurality of optical transmission circuit boards 21 arranged in parallel at predetermined intervals, a main circuit board 3 that fixes the optical transmission circuit boards 21, and The optical transmission circuit board 21 and the casing 22 that accommodates the main circuit board 3 are provided.

  The optical transmission circuit board 21 is mounted with a heat generating electronic component 5 and light emitting elements 6, 7, 8, 9 and is formed in a rectangular shape. The optical transmission circuit board 21 is fixed on one side to the main circuit board 3 via the pin-shaped leads 10 and is electrically connected thereto. The optical transmission circuit board 21 is formed with a sufficiently long length in the direction intersecting with the main circuit board 3 and has a protruding portion 23 protruding outside the casing 22 described later. The protruding portion 23 protrudes from the casing 22 over the entire length of one side of the optical transmission circuit board 21 and constitutes a heat radiation fin that releases the heat of the optical transmission circuit board 21 to the outside. Further, the protruding portion 23 is formed by exposing a metal foil (not shown) for a circuit constituting the substrate to be a solid surface, so as to improve heat dissipation.

  The casing 22 is formed of a metal in a rectangular box shape, and has a slit 24 through which the optical transmission circuit board 21 is inserted. A heat transfer material 25 for forming a heat transfer path between the casing 22 and the optical transmission circuit board 21 is provided in the slit 24. The heat transfer material 25 is made of a heat transfer resin such as heat conductive grease.

  Next, the operation of this embodiment will be described.

  The heat generated from the electronic component 5 is transmitted to the optical transmission circuit board 21 and spreads to the edge of the optical transmission circuit board 21. And the heat which goes to the protrusion part 23 among the edge parts of the circuit board 21 for optical transmission is transmitted to the protrusion part 23, disperse | distributing to the casing 22 via the heat-transfer material 25. FIG. Since the protruding portion 23 protrudes outside the casing 22 and the metal foil having high heat dissipation is exposed, the protruding portion 23 becomes a heat radiating fin and dissipates heat well to lower the heat of the circuit board 21 for optical transmission. Further, the heat transmitted to the casing 22 is also radiated well while spreading over the entire casing 22.

  As described above, the slit 24 for inserting the optical transmission circuit board 21 is formed in the casing 22, and the optical transmission circuit board 21 is protruded from the slit 24. The heat radiation performance can be improved while arranging and reducing the size of the wavelength division multiplexing optical transmission module 20. Further, since the optical transmission circuit board 21 is attached to the main circuit board 3, the circuit can be formed separately into the optical transmission circuit board 21 and the main circuit board 3, and the wavelength division multiplexing optical transmission module 20 is further reduced in size. Can be

  Further, since the heat transfer material 25 is interposed between the casing 22 and the optical transmission circuit board 21, the heat of the optical transmission circuit board 21 can be dispersed in the casing 22, and the heat dissipation can be further improved. it can.

  And since the circuit board 21 for light transmission shall have a metal surface in the protrusion part 23 protruded from the slit 24, the heat dissipation of the protrusion part 23 can be improved.

  Further, since one side portion of the optical transmission circuit board 21 protrudes from the slit 24 over the entire length, heat can be efficiently radiated with a simple structure.

  The heat transfer material 25 is made of a heat transfer resin, but may be made of solder. In this case, the metal foil can be easily grounded by soldering the metal foil and the casing 22.

  Moreover, although the protrusion part 23 made the metal foil for circuits into a solid surface, it exposed and formed the metal surface with good heat dissipation, it does not restrict to this. A metal plate, a metal foil, or the like may be attached to the protruding portion 23 to form a metal surface, or the protruding portion 23 may be plated with metal to form a metal surface.

  The plurality of optical transmission circuit boards 21 are arranged in parallel at a predetermined interval, but the intervals between the optical transmission circuit boards 21 do not have to be the same predetermined interval, and adjacent optical transmission circuits Different intervals may be used for each substrate 21.

  The structure shown in FIGS. 1, 2, and 3 is not limited to the wavelength division multiplexing optical transmission module, but includes a parallel optical transmission module that transmits using a plurality of optical fibers, an optical transmission circuit board, and an optical reception circuit board. The present invention can be applied to other types of optical transmission modules such as optical transceivers arranged in the same manner.

It is a front sectional view of a wavelength division multiplexing optical transmission module. It is a schematic perspective view which shows the internal structure of a wavelength division multiplexing optical transmission module. It is front sectional drawing of the wavelength division multiplexing optical transmission module which shows other embodiment. It is a schematic explanatory drawing of a wavelength division multiplexing optical transmission module and a wavelength division multiplexing optical reception module. It is a top view of the conventional wavelength division multiplexing optical transmission module. It is a disassembled perspective view of the conventional optical transmission module.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wavelength multiplexing optical transmission module 2 Optical transmission circuit board 3 Main circuit board 4 Casing 5 Electronic component 6 Light emitting element 7 Light emitting element 8 Light emitting element 9 Light emitting element 13 Heat transfer protrusion 16 Heat transfer material 20 Wavelength multiplexed optical transmission module 21 Light Transmission circuit board 22 Casing 23 Projection 24 Slit 25 Heat transfer material

Claims (7)

  A plurality of optical transmission circuit boards on which heat-generating electronic components are mounted and light-emitting elements or light-receiving elements are mounted are arranged in parallel at predetermined intervals, and these optical transmission circuit boards are attached to the main circuit board and placed in the casing. An optical transmission module to be accommodated, wherein the casing is provided with a heat transfer protrusion that comes into contact with the electronic component.   The optical transmission module according to claim 1, wherein a deformable heat transfer material is interposed between the electronic component and the heat transfer protrusion.   The optical transmission module according to claim 1, wherein the heat transfer protrusion is formed in a plate shape that partitions the inside of the casing along the optical transmission circuit board.   A plurality of optical transmission circuit boards on which heat-generating electronic components are mounted and light-emitting elements or light-receiving elements are mounted are arranged in parallel at predetermined intervals, and these optical transmission circuit boards are attached to the main circuit board and placed in the casing. An optical transmission module to be accommodated, wherein a slit for inserting the optical transmission circuit board is formed in the casing, and the optical transmission circuit board is protruded from the slit.   The optical transmission module according to claim 4, wherein a heat transfer material is interposed between the casing and the optical transmission circuit board.   6. The optical transmission module according to claim 4, wherein the optical transmission circuit board has a metal surface at a protruding portion protruding from the slit. The optical transmission module according to any one of claims 4 to 6, wherein the circuit board for optical transmission protrudes from the slit over the entire length of one side.

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