JP2006157305A - Optical communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To rationalize the cooling of an optical transmitting/receiving device of high density mounting. <P>SOLUTION: The space between a plurality of front surfaces (26) and back surfaces (18) of the front part (3) respectively opposed to a plurality of modules (6) for optical transmitting/receiving and the front part (3) serves as an air duct (19) which is directed generally in a horizontal direction. The part of an optical fiber cable passes along the air duct (19). An air flow (21) for cooling which passes along the air duct (19) cools the optical fiber cable which exists in the air duct (19), and then rises in a convection to a perpendicular upper part. The rise of the temperature of the air flow which progresses to the downstream along with the horizontally suitable air duct is suppressed to low, and the optical fiber cable which exists in the air duct (19) is cooled by consecutive cooling air flow efficiently. The efficient cooling effectively suppresses the temperature rise of an optical transmitting/receiving module thermally jointed to the optical fiber cable. The miniaturization of the electronic apparatus components which constitute an apparatus as a result can be performed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical communication device, and more particularly to an optical communication device in which an optical transceiver module is air-cooled.

  The development of technology for transceiver modules for optical communication is rapid. In particular, the practical use of small-sized and easy-to-handle optical transmission / reception module products called SFP (Small Form Pluggable Factor) and XFP (10 Gigabit Small Form Factor Pluggable) has been promoted rapidly. Recently, technology development for realizing high performance of small modules has been actively performed. At the development site of optical transmission equipment, before such modules appeared, equipment designers selected semiconductor laser modules, light receiving modules, and various electronic components connected to these modules, and installed their control circuits. It was necessary to design and implement it in the device. Since optical transmission modules such as SFP and XFP are mounted in one small package together with a control circuit and other functional parts, the load on the device designer is greatly reduced. Furthermore, since it is possible to cope with each specification having different performance such as transmission distance and bit rate by replacing the module, the transmission device can be reduced in size, and also in terms of expansion of adaptive capacity, The application of the small transceiver module is functioning effectively.

  To improve the performance of the module, it is necessary to support multiple division systems such as transmission distance expansion, CWDM (Coarse wavelength division multiplexing), and DWDM (Dense wavelength division multiplexing). Coloring of other light sources and other performances are required. Coloring the light source means that the oscillation wavelength of the semiconductor laser is specified to a specific value. Here, it is necessary to note that any element of high performance tends to basically increase the power consumption of the module. As a result, development that prioritized miniaturization has increased power consumption to the extent that heat dissipation cannot be performed if the module remains compact, and cooling like a large heat sink compared to the module itself. Inviting a situation where equipment must be installed.

  The following technical problems remain in the small modules with high performance as described above. In order to increase the transmission distance of the optical transceiver module, it is necessary to add technology such as an increase in optical output and the use of a special modulation technique. Such addition generally leads to an increase in power consumption. In a specification of a module developed for use in 10 Gigabit Ethernet (registered trademark), it is known that the power consumption of a module with a short transmission distance is significantly different from the power consumption of a module with a long transmission distance. In the known technology, as shown in FIG. 10, a plurality of heat sink shapes having different specifications are prepared corresponding to the power consumption. The size of the heat sink (radiation fin) 102 of the small transceiver module 101 of FIG. 10A is larger than the size of the heat sink 104 of the small transceiver module 103 of FIG. Such a difference in size is related to the length of the transmission distance. Longer transmission distance heat sinks are designed for larger sizes. Larger designs are contrary to the design philosophy of providing smaller modules, and the advantages of miniaturization are not fully utilized. Motivation to use small modules in designs that allow for long-distance modules to be mounted, due to significant restrictions on the thickness of the case, the layout of the front of the case, and other design requirements Decreases. In the design limited to the short distance correspondence, it is impossible or difficult to mount the long distance module, and the effectiveness of the small module whose function can be expanded by replacing the module cannot be fully utilized.

  Furthermore, the following problems are found. It is important to stabilize the oscillation wavelength of the semiconductor laser in order to promote the DWDM response by coloring the small module. In order to stabilize the oscillation wavelength, it is essential to add a temperature control function. The addition of the temperature control device increases the power consumption. In a wavelength division multiplexing system such as DWDM, it is intended to increase the transmission capacity of the entire system by processing a large number of wavelength signals, and the number of wavelength signals that can be processed and handled by one transmission apparatus is increased. This leads to expansion of the performance of the apparatus. For this reason, it is required to construct a system capable of mounting a large number of small modules capable of supporting various oscillation wavelengths with high density. The mounting of such a large number of high-density modules is originally a high-density mounting of modules whose power consumption has increased. Therefore, the heat dissipation characteristics deteriorate due to the influence of peripheral modules, resulting in a further increase in power consumption. As a result, power consumption increases synergistically. Such a vicious circle makes device design increasingly difficult. In order to avoid such a vicious circle, mounting of heat radiating fins and airflow technology have begun to be studied, but it is important to pay attention so that the addition of such technology does not impair downsizing as a result. is there. In the multistage technology as shown in FIG. 11, the heat dissipation performance of the heat dissipation fin 105 disposed above the multistage module is invalidated with respect to the lower module 106 of the upper and lower modules, and the heat dissipation path Does not exist. The airflow 107 that cools the radiating fins 105 has a very low cooling efficiency for the lower module 106. A water-cooling device introduced into a high-performance module device that consumes a significant amount of electric power increases the overall size of the device.

  Furthermore, the following problems are found. In devices equipped with a large number of optical transceiver modules, in addition to the above-described problems related to heat dissipation, problems related to the handling of optical fiber cords whose quantities increase are remaining. The optical coupling loss includes a loss inherent to the optical fiber cord itself and a loss inherent to the optical connector for coupling the optical fiber cord and the optical transceiver module. Such fluctuation of the optical coupling loss that greatly affects the communication performance may occur when an operator touches the optical fiber cord and a strong pulling force is applied. Reducing the number of cords is important for reducing the probability of contact with an optical fiber cord that causes fluctuations in optical coupling loss. As a problem of the device that can mount a larger number of optical transceiver modules on the front of the housing at a high density, there is an arrangement such as an arrangement of lamps indicating the operation state and a label indicating the type of module mounting port. A new problem arises that becomes difficult. It is required to avoid the difficulty in recognizing the display.

  Patent Document 1 is known as a technique for solving one of such various problems. The known technology shows a cooling structure in which a large number of electronic components are arranged in an arrangement area where an optical fiber cord between an optical module and an optical connector is arranged, and cooling air is passed through the arrangement area. In the cooling structure, the optical connector is arranged on the upper surface of the apparatus and the electric connector is arranged on the lower surface of the apparatus, so that the air flow is secured and the cooling of the electronic components is made efficient. Such technology gives priority to cooling, and abandons the benefit of making the optical fiber cord easy to access by placing the optical connector on the front side, making actual handling difficult. In addition, the front of the apparatus, which is easy to access, is used as an arrangement area for disposing the air intake port, and the actual operation or the ease of handling is sacrificed. Such a known pigtail type technology, in which the mounting density of the optical module is low and the heat generated by the optical module itself does not reach the entire device, realizes a pluggable type module in which the optical module is mounted at a high density. However, it is inappropriate for realizing a pluggable type module in which optical modules are mounted at a high density.

JP-A-11-67382

The above-mentioned problems of the known technology are (1) the first problem caused by the mounting of the radiation fin, (2) the second problem caused by the air flow, and (3) the third problem caused by the water cooling technique. There are three types of problems.
Regarding the first problem:
Regarding the first problem, the size advantage of the module cannot be utilized due to the attachment of the heat radiation fins. The minimum required size of the radiation fin dilutes the small size of the optical transceiver module. Since the arrangement area of the heat radiating fins is limited to the upper part of the module that is heated, an increase in the size of the module in the height direction cannot be avoided. As a result, the area of the front surface of the housing of the optical communication device increases.
Regarding the second problem:
Regarding the second problem, modules are arranged in multiple stages in a direction perpendicular to the air flow, and modules farther from the fan will swing to the air whose temperature is rising at a closer position, and the heat dissipation efficiency will be significantly reduced. . The points related to FIG. 11 are as described above.
Regarding the third problem:
Regarding the third problem, the water-cooling technique inherently increases the device scale, and the device cost increases significantly.

In view of such problems, the problems of the present invention are as follows.
The subject of this invention is providing the optical communication apparatus which optimizes cooling of the optical transmitter / receiver of high-density mounting.
Another object of the present invention is to provide an optical communication device that optimizes cooling of an optical transceiver that is mounted in front on the optical connector.
Still another object of the present invention is to provide an optical communication device that is small in size and high in performance by improving heat dissipation characteristics and suppressing increase in power consumption.
Still another problem or another problem of the present invention will be described more specifically together with the description of the embodiment.

  The optical communication device according to the present invention forms a front surface portion that is one specific portion of the side surface portions of the housing (1). A cage group (4) is arranged inside the housing. The plurality of optical transmission / reception modules (6) are attached to a plurality of arbitrary cages in the cage group. The plurality of optical fiber cables (7) connect between the optical component (8) mounted inside the housing (1) and the plurality of optical transmission / reception modules (6). Between the plurality of front surfaces (26) and the back surface (18) of the front surface portion (3) respectively facing the front surface portions of the plurality of optical transmission / reception modules (6), there is an air passage (19) that is directed generally in the horizontal direction. Is provided. Part of the fiber optic cable passes through the air path (19).

  The cooling air flow (21) passing through the air passage (19) rises convectively upward in the vertical direction after cooling the optical fiber cable existing in the air passage (19), and along the air passage directed in the horizontal direction. The rise in the temperature of the air flow traveling downstream is kept low, and the optical fiber cable existing in the air passage (19) is cooled with high efficiency by the subsequent cooling air flow. High-efficiency cooling effectively suppresses the temperature rise of the optical transmission / reception module thermally bonded to the optical fiber cable, and as a result, downsizing of the electronic device components constituting the apparatus is enabled.

  The optical fiber cable (7) includes a first part (9) directed from the front surface (26) to the back surface (18), and a second part (11) bent in the direction along the air path with respect to the first part (9). ). The second portion (12) that bends in the direction along the air path and extends along the air path (19) is efficiently cooled by the cooling flow along the air path (19). The optical fiber cable (7) further forms a third portion (14) that is bent from the air passage toward the inner side of the housing substantially perpendicular to the rear surface (18) with respect to the second portion (12). The third part is passed between two cages arranged next to each other substantially parallel to the air passage (19).

  A heat radiating cladding (34) is added to the optical fiber cord (7). The optical fiber cable (7) is covered with a heat radiating cladding (34). The thermal conductivity of the heat dissipating cladding tube (34) is higher than the thermal conductivity of the optical fiber cable (7). The heat dissipating cladding tube (34) promotes heat dissipation by forming fins (35) for increasing the heat dissipation surface.

  Here, a metal female optical connector (36) is usually formed on the front side of the optical transmission / reception module (6), and a connector (for example: connected to the metal female optical connector (36)). A metal male optical connector (23) having a high thermal conductivity is added to the optical fiber cable (7). The male optical connector (23) and the optical fiber cord (7) are thermally bonded to each other. The female optical connector (36) in the front part of the optical transceiver module (6) and the male optical connector (23) that joins the optical fiber cord (7) are thermally joined via metal. The heat of the transmission / reception module (6) can be guided at high speed to the air path (19) via the female optical connector (36), the male optical connector (23), and the optical fiber cord (7). Is advantageous. The improvement of the heat dissipation of the optical fiber cord (7) and the coupling between the metal parts of the male and female connectors can synergistically increase the efficiency of cooling of the optical transceiver module (6).

  The above-described arrangement of the air passage (19) in the housing is advantageous in that the front portion can be simply opened and closed as a result. The open / close flexibility facilitates the work of newly installing or replacing the optical transceiver module.

  The optical transceiver module has a built-in laser oscillation element. A laser oscillation element used in the DWDM system is cooled by a Peltier element. In this case, the cooling of the optical transmission / reception module by cooling the optical fiber cable validates the cooling operation of the laser oscillation element by the Peltier element with good circulation.

  The optical communication apparatus according to the present invention can optimize the cooling of a high-density mounting optical transmission / reception apparatus, and has many effects as a result of the cooling.

  The best mode for carrying out the optical communication apparatus according to the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, the peripheral wall of the casing body (housing) 1 of the optical communication device is formed of a bottom surface portion 2 and a side surface portion. A specific part of the side part is formed as a front part 3. The front surface portion 3 is formed to be openable and closable with respect to the bottom surface portion 2 or another bottom surface portion. The front surface part 3 can be opened and closed as a whole or as a part of the opening / closing door 3 ′. The cage group 4 is arranged to be joined to the upper surface (inner surface) of the bottom surface portion 2. The cage group 4 is a set of unit cages 5 arranged side by side in the horizontal direction (example: horizontal direction) and unit cages 5 stacked in multiple stages in the vertical direction (example: vertical direction). It is possible to provide a gap between two unit cages 5 adjacent in the vertical direction, and it is possible to provide a gap between two unit cages 5 adjacent in the horizontal direction. The optical transceiver module 6 is mounted on a plurality of unit cages 5 selected from a large number of unit cages 5. FIG. 1 shows eight optical transmission / reception modules 6 mounted in eight unit cages 5 out of 22 unit cages 5. The remaining 14 unit cages 5 are prepared for selectively mounting other optical transceiver modules. Additional cages are possible. Other optical transmission / reception modules are arbitrarily added in response to an increase in transmission capacity. When the optical transceiver module is added, the opening / closing function of the front surface portion 3 is utilized. Additional work of the optical transceiver module is possible during operation of the optical communication device.

  The heat radiating optical fiber cord 7 is optically connected to each of the optical transceiver modules 6. The number of heat-dissipating optical fiber cords 7 is one or more for one optical transceiver module 6. An optical component (for example, a demultiplexing filter) 8 is mounted on the upper surface of the bottom surface portion 2. The heat dissipating optical fiber cord 7 connects between the optical transceiver module 6 and the optical component 8. The heat-dissipating optical fiber cord 7 to be bent is formed as seven bent portions as shown in FIG. The first bent portion 9 is formed as a forward portion toward the front surface portion 3 from the front side of the optical transmission / reception module 6 (the surface of the optical transmission / reception module 6 facing the front surface portion 3). The second bent portion 11 is formed as a first bent portion that bends in the lateral direction (horizontal direction parallel to the inner surface of the front face portion 3) with respect to the first bent portion 9. The third bent portion 12 is formed as a first straight portion that proceeds in the above-described lateral direction with respect to the second bent portion 11. The fourth bent portion 13 is formed as a second bent portion that bends in the rear surface direction with respect to the second bent portion 11. The fifth bent portion 14 is formed as a reverse portion that moves backward with respect to the fourth bent portion 13. The sixth bent portion 15 is formed as a third bent portion that bends in the lateral direction with respect to the fifth bent portion 14 and changes the direction with respect to the optical component 8. The seventh bent portion 16 is formed as a second straight portion that goes straight toward the optical component 8 in the lateral direction with respect to the sixth bent portion 15. The heat-radiating optical fiber cord 7 is actually bent more smoothly (for example, in a circular shape) and extends from the optical transceiver module 6 to the optical component 8. Thus, the heat-radiating optical fiber cord 7 reaches the optical component 8 while turning toward the optical component 8 located behind the optical transmission / reception module 6 after going from the optical transmission / reception module 6 to the front surface portion 3. . A part of the heat dissipating optical fiber cord 7, in particular, the fifth bent portion 14 of the heat dissipating optical fiber cord 7 passes between the two optical transmission / reception modules 6 or the unit cages 5 adjacent in the lateral direction. Such bending characteristics including straightness are common to a plurality of other heat-dissipating optical fiber cords 7.

  As shown in FIG. 3, a space having an appropriate width D is provided between the facing surface 17 facing the front surface portion 3 of the cage group 4 and the inner surface (back surface) 18 of the front surface portion 3. Such a space is used as the air passage 19. The height width in the vertical direction of the air passage 19 extending in the lateral direction substantially corresponds to the height of the cage group 4. As shown in FIG. 1, the cooling air 21 is forced through the air passage 19 in the lateral direction. A cooling fan 22 is used to create a lateral forced flow. The cooling fan 22 is disposed on one side wall that intersects the front surface portion 3.

  As shown in FIG. 3, a metal female connector 36 (see FIG. 2) is attached to the front side of the optical transmission / reception module 6, and an optical connector that joins the heat-radiating optical fiber cord 7 (example: Male type) 23 is detachably fixed to each. The optical connector 23 is conventionally made of resin, but the optical connector 23 of this embodiment is formed of a material having high thermal conductivity (example: metal, silicon). One end portion of the heat-dissipating optical fiber cord 7 is joined to the optical connector 23 directly or indirectly, and mechanically and thermally to the optical connector 23. Therefore, the heat of the optical connector 23 is transmitted to the cooling air 21 in the air passage 19. Further, the heat in the air path region portion of the heat-radiating optical fiber cord 7 existing in the air path 19 is transmitted to the cooling air 21 in the air path 19. As the air path region portion, FIG. 2 illustrates a first bent portion 9, a second bent portion 11, a third bent portion 12, and a fourth bent portion 13.

  As shown in FIG. 4, the air path 19 includes the inner surface 18 of the bottom surface portion 2, the inner surface 25 of the lid casing housing 24, the front surface of the cage group 4, particularly the front surface 26 of the optical transceiver module 6, and the front surface portion 3. It advances in a substantially horizontal direction by a rectangular parallelepiped rod-shaped air passage formed by four surfaces of the inner surface 27 of the inner surface. In the most preferable mode, the cooling air 21 in such an air passage flows in the horizontal direction in the air passage 19 formed on the front side of the cage group 4 and is directed to the horizontal direction orthogonal to the air flow. Heat is taken from the first bent portion 9 and heat is taken from the third bent portion 12 that extends long in the wind flow direction. Each of the multiple heat-dissipating optical fiber cords 7 has thermal conductivity, and transmits heat generated by the optical transmission / reception module 6 to the heat-dissipating optical fiber cord 7 located far from the optical transmission / reception module 6. The air flow that takes heat away from the heat-dissipating optical fiber cord 7 is diffused by turbulent flow and mixed with a lower temperature flow to generate heat from other parts of the heat-dissipating optical fiber cord 7. Take away. The air flow whose temperature has risen is discharged to the outside through an air discharge window (not shown) opened on the other side wall facing the cooling fan 22. The flow of the cooling air 21 is not a convection due to a temperature rise but a forced flow directed in the horizontal direction, and its cooling efficiency is high. When the heat-dissipating optical fiber cord 7 has high heat dissipation and high thermal conductivity, its cooling efficiency increases dramatically.

  The number of heat-dissipating optical fiber cords 7 connecting one optical transceiver module 6 and the optical component 8 is the total number of transmission and reception. A plurality of heat dissipating optical fiber cords 7 are collected together as a bundle of optical fiber cords before reaching the optical component 8. Multiple bundles are combined into a larger bundle. As a preferred form of the optical component 8, an optical element that demultiplexes a plurality of optical signals into one or a small number of optical fiber cords is assumed, such as a wavelength demultiplexing filter for DWDM. The net connection cord 28 for connecting the optical component 8 to an external network is optically connected between the optical connection connector 29 attached to the front surface portion 3 and the optical component 8 in the casing body 1. The number of net connection cords 28 for transmitting / receiving optical demultiplexing signals is dramatically smaller than the total number of optical transmission / reception modules 6, the size of the optical connection connector 29 is remarkably small, and compact at the corner of the front surface portion 3. It is installed. For this reason, in addition to the opening / closing door 3 ′, the front surface portion 3 has only a small device having a small display area such as an operation display lamp, and the front surface portion 3 can be easily opened and closed. There are no obstacles for it. By opening and closing the open / close door 3 ′, work efficiency such as replacement of the optical transceiver module 6 and new installation of the optical transceiver module 6 is high, and the benefits of high-density mounting can be enjoyed effectively.

  FIG. 5 shows a test apparatus for confirming the cooling effect. One cage 5 ′ identical to the unit cage 5 is placed on the test board 31 having a horizontal plane, and the same optical transceiver module 6 ′ as the optical transceiver module 6 is connected to the unit cage 5 ′. The same two heat-dissipating optical fiber cords 7 ′ as the heat-dissipating optical fiber cords 7 are connected to the optical transceiver module 6 ′. Two temperature measuring elements 32 are arranged at two points P1 and P2 of the unit cage 5 '. In this experiment, for the purpose of confirming the effect of the heat-dissipating optical fiber cord 7, the airflow 21 is guided only to the heat-dissipating optical fiber cord 7, and the airflow is directly applied to the front optical connector portion of the optical transceiver module 6. Is considered to be an unguided arrangement.

FIG. 6 shows the test results. The four positions A1, A2, B1, and B2 on the horizontal axis indicate the following.
A1: Conventional fiber cord used, no air flow A2: Conventional fiber cord used, with air flow B1: Heat radiating fiber cord used, no air flow B2: Heat radiating fiber cord used, with air flow Coordinate point display marks in the graph indicate the following .
Diamond: Measured temperature at point P1 Square shape: Measured temperature at point P2 Triangle: Internal temperature of unit cage 5 'Round shape: Power consumption The vertical axis on the left indicates temperature, and the vertical axis on the right indicates power consumption (relative ratio) Yes.

  When using conventional fibers, there is no significant difference in temperature and power consumption depending on the presence or absence of airflow. In the case of using a heat-dissipating fiber, both the temperatures at both points P1 and P2, the temperature in the module, and the power consumption are significantly reduced. In particular, when a heat-dissipating fiber is used and air is supplied, all the test items of both the temperatures at both points P1 and P2, the temperature in the module, and the power consumption are further significantly reduced. The cooling of the heat-radiating optical fiber cord 7 has been found to have remarkable characteristics corresponding to the reduction of power consumption.

  FIG. 7 shows a preferred form of the optical transceiver module 6. An optical transceiver module 6 is detachably attached to the unit cage 5. As described above, the female optical connector 36 is formed on the front side of the optical transceiver module 6, and the optical connector 23 is coupled to the female optical connector 36. The female optical connector 36 is conventionally made of metal. The optical connector 23 can be attached to and detached from the front portion of the optical transceiver module 6. The user or the designer can open the open / close door 3 'and attach the optical connector 23 to which the end of the heat-dissipating optical fiber cord 7 is fixed to the optical transceiver module 6; It can be extracted from the transceiver module 6.

  The surface side of the part belonging to the air passage 19 in the heat dissipating optical fiber cord 7 is closely surrounded by the heat dissipating cladding 34 as shown in FIG. The heat-radiating cladding tube 34 is a cylindrical body made of a highly heat-conductive material that is in close contact with the central heat-radiating optical fiber cord 7, and the cylindrical body protrudes in the radial direction and is arranged in the circumferential direction. A number of protruding fins 35 are provided. The protruding fins 35 are formed as ribbon-shaped protrusions that are thin enough to sway by the cooling air 21. Such a protrusion may be formed as a needle-like sharp conical protrusion. The ribbon-like protrusion can be wound around the heat-radiating optical fiber cord 7 in a spiral shape. Between adjacent projections 35, a local air passage 35 is formed that extends linearly, spirally, or irregularly continuously in the axial direction of the heat-radiating optical fiber cord 7. The cooling air 21 passing through the projecting fins 35 in a certain direction efficiently cools the heat-radiating cladding tube 34. The optical connector 23 is cooled by the cooling of the heat radiating cladding 34, and as a result, the optical transceiver module 6 is cooled.

  The optical transmission / reception module 6 in a preferred usage form can be applied as part of a DWDM system. Such an optical transceiver module 6 is strongly required to stabilize the oscillation wavelength of a semiconductor laser that is one of the electronic components constituting the optical transceiver module 6. For the stabilization, constant control of the temperature of the semiconductor laser is particularly important. A Peltier element for temperature stabilization is attached to the main body portion of the semiconductor laser. The power consumption of the Peltier element increases corresponding to the temperature difference between the control target temperature and the external temperature. The Peltier element has a nonlinear physical property that increases the amount of heat generated in response to an increase in power consumption. In the optical transceiver module 6 in which the Peltier element having such physical properties is used, in order to stably operate the Peltier element and reduce the temperature difference, the heat generated in the Peltier element can be released with high efficiency. is important. The heat-dissipating optical fiber cord 7 having both high heat dissipation and thermal conductivity can reduce the above-described temperature difference to the optimum.

  Optical transceiver modules that are made smaller and more dense have a smaller heat capacity, so it is more difficult to reduce the temperature difference, especially in the case of 10 Gbps optical transceiver modules. The difficulty becomes even more pronounced when the temperature difference is intended to be reduced by the Peltier element, but in the present invention, the temperature difference can be reduced, so that the oscillation wavelength of the semiconductor laser of the high-performance compact optical transceiver module can be reduced. Can be effectively controlled to be constant. Not only does the heat-dissipating optical fiber cord 7 have heat dissipation, but the optical connector 23 also has heat dissipation, so that the effect of reducing the temperature difference is effectively exhibited synergistically. The entire heat-dissipating optical fiber cord 7 and the optical connector 23 that promote heat dissipation promote the effect of increasing the effective heat capacity of the optical transmission / reception module 6, so that the effect of a constant temperature difference further exists and the oscillation wavelength is stabilized Is further promoted. Since the optical connector 23 and the end of the heat-dissipating optical fiber cord 7 are close to the optical transceiver module 6 and the cooling rate is fast, the stability effect is dramatically increased.

  FIG. 9 shows an improvement in heat transfer efficiency. In order to thermally and mechanically connect the large-diameter front surface portion 3 of a high heat transfer coefficient material (example: metal, silicon) and the small-diameter heat-dissipating optical fiber cord 7 of the high heat transfer coefficient material, a high heat transfer coefficient A thermal connection cladding tube (elastic tube) 37 made of a material (metal, high heat transfer rate powder-containing rubbery (silicone) material) is effectively used. The outer peripheral surface of the thermal connection cladding tube 37 is formed in a conical surface shape. The conical surface shape is effective in both thermal connection and mechanical connection of the thick optical connector 23 and the thin fiber cord 7.

FIG. 1 is an oblique projection showing a preferred embodiment of an optical communication apparatus according to the present invention. FIG. 2 is a plan view showing a bent form of the optical fiber cord. FIG. 3 is a plan view showing the arrangement relationship between the bending of the optical fiber cord and the air path. FIG. 4 is a front sectional view showing the relationship between the bending of the optical fiber cord and the arrangement of the optical fiber connectors. FIG. 5 is a plan view showing the test apparatus. FIG. 6 is a graph showing the test results. FIG. 7 is a plan view showing a preferred form of the optical fiber cord. FIG. 8 is a cross-sectional view of the optical fiber cord. FIG. 9 is a front view showing the cladding tube. FIGS. 10A and 10B are oblique axis projection views showing a plurality of known heat sinks. FIG. 11 is an oblique projection showing a known cooling technique.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Housing | casing 3 ... Front part 4 ... Cage group 6 ... Optical transmission / reception module 7 ... Optical fiber cable 8 ... Optical component 9 ... 1st part 11 ... 2nd part 14 ... 3rd part 18 ... Back surface 19 ... Air path 21 ... Air flow for cooling 23 ... Optical connector 26 ... Front face 34 ... Heat dissipating cladding 35 ... Fin 36 ... Female optical connector

Claims (10)

A front part which is one specific part of the side parts of the housing;
A cage group disposed inside the housing;
A plurality of optical transmission / reception modules mounted in any of a plurality of cages of the cage group;
An optical component mounted inside the housing;
Comprising a plurality of optical fiber cables connecting between the optical transceiver module and the optical component;
Between the front surfaces of the plurality of optical transmission / reception modules respectively opposed to the front surface portions and the back surfaces of the front surface portions, a wind path is provided in a substantially horizontal direction, and a part of the optical fiber cable is the air path. Optical communication device that passes through. A first optical connector is attached to the optical transmission / reception module, the optical fiber cable includes a second optical connector, and the optical fiber cable transmits the optical transmission / reception via the second optical connector and the first optical connector. The optical communication device according to claim 1, wherein the first optical connector and the second optical connector connected to the module for use are thermally joined by a member having high thermal conductivity. The optical fiber cable is
A first portion from the front to the back;
The optical communication device according to claim 1, further comprising: a second part that bends in a direction along the air path with respect to the first part and extends along the air path. The optical communication device according to claim 3, further comprising a third portion that is bent from the air passage toward the inside of the housing substantially perpendicularly to the rear surface with respect to the second portion. The optical communication device according to claim 4, wherein the third portion is passed between two cages arranged adjacent to each other substantially parallel to the air passage. A heat-dissipating cladding tube is further provided, and the optical fiber cable is covered with the heat-dissipating cladding tube, and the thermal conductivity of the heat-dissipating cladding tube is higher than the thermal conductivity of the optical fiber cable. The optical communication device according to claim 1. The optical communication apparatus according to claim 6, wherein the heat dissipating cladding tube includes fins for increasing the heat dissipation surface. Further comprising a heat radiating cladding, the optical fiber cable is coated with the heat radiating cladding, the thermal conductivity of the heat radiating cladding is higher than the thermal conductivity of the optical fiber cable,
An optical connector mounted on the optical transceiver module on the front side of the optical transceiver module;
The optical communication apparatus according to claim 1, wherein the optical connector and the optical fiber cord are thermally bonded. The optical communication device according to claim 1, wherein the front surface part is freely openable and closable. The optical communication device according to claim 1, wherein the optical transmission / reception module includes a laser oscillation element, and the laser oscillation element is cooled by a Peltier element.

Images