JP5075140B2 - Parallel optical transmission equipment - Google Patents

Description

  The present invention relates to a parallel optical transmission device used in an inter-board optical transmission system and an inter-device (between housing) optical transmission system, and in particular, a type in which an optical module having an optical element and an electrical element is attached to an electrical pluggable socket. The present invention relates to a parallel optical transmission apparatus.

  In recent years, high-end system devices such as supercomputers tend to achieve large capacity and high speed of information communication by parallel operation of a plurality of CPUs (central processing units). Ports and system devices in this system device There is a demand for high-capacity, high-speed and high-density information signal transmission. Only the electrical transmission system that transmits information signals as electrical signals is reaching a limit from the viewpoint of transmission speed, transmission loss, and the like, so that signal transmission by an optical interconnection system using optical transmission has been put into practical use. The optical interconnection system has an advantage that a signal transmission system using an optical module having a small size and low power consumption can be constructed while being able to perform signal transmission in a much wider band than the electrical transmission system.

By the way, the technique of electrically connecting electrical elements, such as IC, and the connection terminal on an electrical board via a socket is known (for example, refer patent document 1, patent document 2, and nonpatent literature 1).
Patent Document 1 discloses a heat sink mounting structure in which a heat sink is mounted on an MPU attached to an IC socket. In this heat sink mounting structure, the pressure-receiving surface of the heat sink is press-fixed to the MPU by alternately engaging linear springs arranged on the opposite end surfaces of the heat sink with the locking claws of the IC socket and the pin-shaped fins of the heat sink. . Patent Document 2 discloses a technique for pressing a socket from the top of a heat sink using a spring material. In Non-Patent Document 1, a spring is provided on the heat sink.

JP 2004-8385 A Special table 2008-502002 gazette

Cinapse Design Guide 2005

By the way, in the prior art disclosed in Patent Document 1, since the local stress is applied to the locking claw of the IC socket, the IC socket may be deformed (warped). Further, the technique disclosed in Non-Patent Document 1 has a problem that the size in the height direction becomes large and the card cannot be inserted into the card slot.
The present invention has been made in view of such conventional problems, and its purpose is to uniformly apply a pressing force to each connection terminal portion of the electric pluggable socket, which is small and improved in reliability. It is an object of the present invention to provide a parallel optical transmission device that achieves the above.

  In order to solve the above problem, the parallel optical transmission device according to the first aspect of the present invention includes a bottom wall portion on which a plurality of connection terminal portions are disposed, and a peripheral wall portion that forms a module housing recess, An electric pluggable socket fixed on the electric board, and is detachably mounted in the module housing recess, and is electrically connected to the electric board through the connection terminal portion of the socket when mounted, and transmits an electric signal. An optical module that converts a signal or an optical signal into an electrical signal; a pressing member that is detachably fixed to the peripheral wall portion by pressing the optical module and the socket from above to apply a pressing force; An optical connector for transmitting the optical signal in parallel with the module, and a step formed between the upper surface of the peripheral wall and the upper surface of the optical module between the socket and the pressing member. Wherein the provided spacer having a thickness to fill.

  According to this configuration, when the pressing member is fixed to the electric pluggable socket with a screw or the like, the step formed between the upper surface of the socket peripheral wall portion and the upper surface of the optical module is absorbed by the spacer, and local stress is applied to the socket. Is mitigated and the deformation of the socket is suppressed. As a result, it is possible to apply a uniform pressing force to each connection terminal portion of the electric pluggable socket, and reduce the load (shearing force) on each screw when the pressing member is fixed to the socket with a plurality of screws. Can improve reliability. In addition, since no spring is used, the size in the height direction can be reduced.

The parallel optical transmission apparatus according to another aspect of the present invention is characterized in that the plurality of electrical connection terminal portions are electrically connected when receiving a predetermined pressing force.
The parallel optical transmission apparatus according to another aspect of the present invention is characterized in that the spacer is made of an elastic material. According to this configuration, when the pressing member is fixed to the socket with a screw or the like, the generation of local stress is further mitigated by the elastic deformation of the spacer. The spacer is made of, for example, a soft resin such as Teflon (registered trademark) or an elastic material such as rubber.

  The parallel optical transmission apparatus according to another aspect of the present invention is characterized in that the spacer has a thickness larger than the step. According to this configuration, since the manufacturing variation of the step is absorbed by the elastic deformation of the spacer having a thickness larger than the step, the generation of local stress is further alleviated.

  The parallel optical transmission apparatus according to another aspect of the present invention is characterized in that the spacer is a sheet-like elastic body disposed on the entire upper surface of the peripheral wall portion of the socket. According to this configuration, heat generated in the optical module is efficiently transmitted to the pressing member side via the sheet-like spacer, so that heat dissipation efficiency is improved.

  The parallel optical transmission apparatus according to another aspect of the present invention is characterized in that the spacer is formed of an elastic material having high thermal conductivity. According to this configuration, the heat generated in the optical module is efficiently transmitted to the pressing member side through the spacer formed of an elastic material having high thermal conductivity, so that the heat dissipation efficiency is further improved. The spacer is made of, for example, an elastic material having high thermal conductivity such as rubber containing metal fibers (rubber containing metal filler) or ceramic filler-containing rubber.

The parallel optical transmission apparatus according to another aspect of the present invention is characterized in that a portion of the peripheral wall portion of the socket and a portion on the spacer side is formed of a material having high thermal conductivity. According to this configuration, heat generated in the optical module is transmitted to a part of the socket peripheral wall portion formed of an elastic material having high thermal conductivity, and further efficiently transmitted to the holding member side through the spacer. Is further improved.
In the parallel optical transmission apparatus according to another aspect of the present invention, the spacer is formed of a plurality of materials having different elastic forces, and is arranged according to the pressing force between the pressing member and the peripheral wall portion. It is characterized by.

  ADVANTAGE OF THE INVENTION According to this invention, a pressing force can be uniformly applied to each connection terminal part of an electric pluggable socket, and it can implement | achieve the parallel optical transmission apparatus which aimed at the improvement of reliability small.

1 is an exploded perspective view showing a schematic configuration of a parallel optical transmission apparatus according to an embodiment of the present invention. The perspective view which shows the state which mounted | wore the optical module with the optical connector. The perspective view which shows the assembly state of the parallel optical transmission apparatus which concerns on one Embodiment. The top view which shows the state which mounted | wore the optical module with the optical connector. The longitudinal cross-sectional view which shows the state which mounted | wore the optical module with the optical connector. The fragmentary sectional view which expanded and showed a part of FIG. The top view which shows the state which has arrange | positioned the spacer on the electric pluggable socket. The side view of FIG. (A)-(c) shows the example of the cross-sectional structure of a spacer, (a) is a rectangular cross-sectional shape, (b) is a trapezoidal cross section, (c) is a rectangular-shaped base. Sectional drawing which respectively shows what formed the dot and stripe of a rectangle or a triangle on. The top view which shows one Example of a spacer.

Next, an embodiment of the present invention will be described with reference to the drawings. In the description of each embodiment, similar parts are denoted by the same reference numerals, and redundant description is omitted.
A parallel optical transmission apparatus 10 according to an embodiment will be described with reference to FIGS.
As shown in FIG. 1, the parallel optical transmission device 10 includes an electric board 5, an electric pluggable socket 1, an optical module 3, a pressing member 2, a heat sink 20, an optical connector 4, and an optical component 60. ing.

  The electric substrate 5 is a PCB (Printed Circuit Board), and a plurality of electric terminals 51 and electrode patterns (not shown) connected to the electric terminals 51 are formed on the front and back surfaces thereof. The plurality of electrical terminals 51 are, for example, LGA (Land Grid Array) terminals in which fine flat electrodes are arranged in a grid pattern. In addition, as shown in FIG. 1, the electric board 5 has four through holes 52 through which screws 61 for fastening the electric pluggable socket 1 to the electric board 5 are inserted, and the electric pluggable socket 1 is positioned on the electric board 5. A pair of positioning pin holes 53 are formed for this purpose.

  As shown in FIGS. 1, 4 and 5, the electric pluggable socket 1 includes a bottom wall portion 11 in which a plurality of connection terminal portions 13 that are electrically connected when a predetermined pressing force is received, And a peripheral wall portion 12 that forms a module housing recess 14 for housing the module 3, and is fixed on the electric substrate 5 with screws 61. The plurality of connection terminal portions 13 are arranged in a lattice pattern, and an upper contact pin 13a (see FIG. 1) protruding from the surface of the bottom wall portion 11 and a lower contact pin (not shown) protruding from the back surface thereof. Each has. Each of the connection terminal portions 13 is a spring-like structure configured such that when a predetermined pressing force is applied, a coiled spring portion (not shown) contracts and the upper contact pin 13a and the lower contact pin are electrically connected. Terminal. Further, as shown in FIG. 1, four screw holes 15 into which screws 61 are screwed and screws 62 for fastening the pressing member 2 to the electric pluggable socket 1 are screwed on the peripheral wall portion 12 of the electric pluggable socket 1. Four screw holes 17 are formed. Further, as shown in FIGS. 3 and 4, a cutout portion 12 a that accommodates a portion of the connector portion 42 (see FIG. 2) of the optical connector 4 is formed in a part of the peripheral wall portion 12.

  The optical module 3 has a function of converting an electrical signal into an optical signal, and is detachably mounted in the module housing recess 14 of the electrical pluggable socket 1 (see FIGS. 4 and 5). When the optical module 3 is mounted in the module housing recess 14, the optical module 3 is electrically connected to the electric substrate 5 via the plurality of connection terminal portions 13 of the electric pluggable socket 1. As shown in FIGS. 1 and 2, the optical module 3 is arranged in a module substrate (ESA substrate) 34 and a recess 34a of the module substrate 34, and a plurality of (this example) mounted on an electrode pattern (not shown). 12) optical elements 32, an IC (see FIG. 6) 33 mounted on the electrode pattern of the module substrate 34, and a module cover 35. The IC 33 is flip-chip mounted (FCB: Flip Chip Bonding) on one surface (front surface) of the module substrate 34 and is electrically connected to the plurality of optical elements 32 by wiring.

  The module substrate 34 is a ceramic substrate. On one surface (front surface) of the module substrate 34, one set of two differential signal terminals is provided, and a plurality of sets of differential signal terminals having the same number as the number of channels (12 channels in this example) and power are supplied to the IC. A plurality of power supply terminals for supplying control signals, a plurality of control signal supplying terminals for supplying control signals to the IC, and a ground pattern are formed. The other surface includes a plurality of terminals (differential signal terminals, electrically connected to a plurality of sets of differential signal terminals, a plurality of power supply terminals, and a plurality of control signal supply terminals on one surface. A power supply terminal and a control signal supply terminal) and a ground pattern electrically connected to the ground pattern on one surface.

  In the present embodiment, the plurality of optical elements 32 are configured by a laser diode array having a plurality of surface-emitting type semiconductor laser elements aligned in a line. A surface emitting semiconductor laser element as an optical element is a VCSEL (Vertical Cavity Surface Emitting Laser) that emits light (optical signal) in a direction perpendicular to the substrate surface (upward in FIG. 5). The IC 33 is a driver IC that drives the plurality of optical elements 32.

  As shown in FIGS. 1 and 3, the holding member 2 holds the optical module 3 and the electric pluggable socket 1 from above so as to apply a predetermined pressing force to each connection terminal portion 13 of the electric pluggable socket 1. The pluggable socket 1 is detachably fixed to the peripheral wall portion 12. The pressing member 2 has four through holes 23 through which the screws 62 are inserted. The holding member 2 is fixed to the electric pluggable socket 1 by inserting screws 62 through the four through holes 23 and screwing the screws 62 into the four screw holes 17 of the electric pluggable socket 1. A heat sink 20 is integrally formed on the upper surface of the pressing member 2.

  The optical connector 4 transmits optical signals in parallel with the plurality of optical elements 32 of the optical module 3. As shown in FIGS. 1 and 2, the connector 4 includes a tape fiber 41 in which a plurality of optical fibers (12 in this example) are arranged in a line, and a connector portion (ferrule) holding the plurality of optical fibers. 42) and an optical component that optically couples light (optical signals) emitted from the plurality of optical elements 32 in a perpendicular direction to the respective end faces of the plurality of optical fibers held by the connector portion 42 after bending by 90 degrees. 60.

  The connector part 42 is a multi-core ferrule connector (MT connector). The connector portion 42 is disposed in the window 21 of the pressing member 2 in a state where the pressing member 2 is fixed to the electric pluggable socket 1. The tape fiber 41 is connected to another optical connector 43 and transmits optical signals to and from the optical module 3 in parallel.

  The optical component 60 includes two sets of microlens arrays 64 and 65 each having a plurality of (in this example, twelve) microlenses arranged in a line, and a reflecting surface 66. The optical component 60 enters light emitted from each optical element 32 in a direction perpendicular to the optical element 32 via the microlens array 65 as shown by an alternate long and short dash line in FIG. The reflected light is collected by the microlens 64 and optically coupled to the end faces of the optical fibers of the connector section 42.

  The connector part 42 and the optical component 60 of the optical connector 4 are, for example, fitted with two guide pins (not shown) protruding from the optical part 60 in two guide pin holes (not shown) of the connector part 42, It is fixed by bonding. The connector part 42 and the optical component 60 fixed in this way are connected to the module cover 35 of the optical module 3 mounted in the module receiving recess 14 of the electric pluggable socket 1 as shown in FIGS. It is mounted in the opening 3a and is fixed to the module cover 35 with an adhesive.

  Further, as shown in FIG. 1, the parallel optical transmission device 10 includes a sheet-like heat conducting member 30 for efficiently transmitting heat generated by the IC 33 of the optical module 3 to the holding member 2 and the heat sink 20. It is arranged between the member 2. The heat conducting member 30 is made of a material having high heat conductivity, such as silicon grease or graphite sheet.

  Further, as shown in FIGS. 1, 7, and 8, the parallel optical transmission apparatus 10 is provided between the electric pluggable socket 1 and the pressing member 2 so that the upper surface of the peripheral wall portion 12 of the electric pluggable socket 1 and the optical module 3 are connected. A spacer 40 having a thickness that fills a step 50 (see FIG. 5) formed between the upper surface of the module cover 35 is provided.

The spacer 40 is made of, for example, a soft resin such as Teflon (registered trademark) or an elastic material such as rubber. The spacer 40 has a thickness larger than the step 50. However, this thickness is set to a thickness that does not hinder electrical contact during pressing. Further, as shown in FIGS. 7 and 8, the spacer 40 is a sheet-like elastic body disposed on the entire upper surface of the peripheral wall portion 12 of the electric pluggable socket 1. The spacer 40 is preferably formed of an elastic material, but if reuse is not required, a member such as a gasket other than an elastic body that is deformed by the pressing force between the pressing member 2 and the peripheral wall portion 12 should be used. You can also.
FIG. 3 shows a state in which the parallel optical transmission apparatus 10 having the above configuration is assembled. The parallel optical transmission device 10 according to the embodiment having such a configuration has the following operational effects.

  When the pressing member 2 is fixed to the electric pluggable socket 1 with the screw 62, the step 50 formed between the upper surface of the peripheral wall portion 12 of the socket and the upper surface of the module cover 35 of the optical module 3 is absorbed by the spacer 40, Generation of local stress in the electric pluggable socket 1 is alleviated, and deformation of the electric pluggable socket 1 is suppressed. Thereby, it is possible to apply a uniform pressing force to each connection terminal portion 13 of the electric pluggable socket 1, and when fixing the pressing member 2 to the socket with a plurality of screws 62, a load (shear) is applied to each screw 62. Power) can be reduced, and reliability is improved. In addition, since no spring is used, the size in the height direction can be reduced.

  Since the spacer 40 is formed of a soft resin such as Teflon (registered trademark) or an elastic material such as rubber, the spacer 40 is elastically deformed when the pressing member 2 is fixed to the electric pluggable socket 1 with the screw 62. This further reduces local stress generation.

  Since the spacer 40 has a thickness larger than the step 50, the manufacturing variation of the step 50 is absorbed by the elastic deformation of the spacer 40 having a thickness larger than the step 50, and the generation of local stress is further alleviated.

Since the configuration using the electric pluggable socket 1 is used, if a failure occurs in the optical module 3, the pressing member 2 is removed, the optical module 3 is removed from the module housing recess 14 and replaced, and a new optical module is replaced with the module housing recess. 14 and the pressing member 2 may be fixed to the electric pluggable socket 1 with screws 62. For this reason, the maintenance becomes easier than in the case where the optical module 3 is soldered to the electric substrate 5, the cost is reduced, and the reliability is improved.
In addition, this invention can also be changed and embodied as follows.

  -In the parallel optical transmission apparatus 10 which concerns on the said one Embodiment, you may form the spacer 40 with an elastic material with high heat conductivity. The spacer 40 is formed of, for example, an elastic material having high thermal conductivity such as rubber containing metal fibers (rubber containing metal filler) or ceramic filler-containing rubber. In this configuration, heat generated in the IC 33 of the optical module 3 is efficiently transmitted to the holding member 2 and the heat sink 20 via the sheet-like spacer 40 formed of an elastic material having high thermal conductivity. Further improvement.

  In the parallel optical transmission apparatus 10 according to the above-described embodiment, as shown in FIG. 8, a part 12 </ b> A on the spacer 40 side is formed of a material having a high thermal conductivity as a part of the peripheral wall part 12 of the electric pluggable socket 1. It is preferable to do this. That is, the peripheral wall portion 12 of the electric pluggable socket 1 is composed of two parts, a first portion 12B formed of an insulating material and a second portion 12A formed of a material having high thermal conductivity. Both parts 12A and 12B are separately molded and integrated. A portion 12A which is a part of the peripheral wall portion 12 of the electric pluggable socket 1 is made of a material having high thermal conductivity (thermal conductive material), for example, an alloy of Cu (copper) and W (tungsten). In this configuration, heat generated in the IC 33 of the optical module 3 is transmitted to the first portion 12A of the socket peripheral wall portion 12 formed of an elastic material having high thermal conductivity, and further to the pressing member 2 side via the spacer 40. Since it is transmitted efficiently, the heat dissipation efficiency is further improved.

  -In the parallel optical transmission apparatus 10 which concerns on the said one embodiment, although the spacer 40 is made into the sheet-like elastic body arrange | positioned at the whole upper surface of the surrounding wall part 12 of the electric pluggable socket 1, one sheet-like elastic body is used. The parallel optical transmission apparatus 10 including a plurality of spacers arranged on the upper surface of a plurality of divided parts or a plurality of spacers arranged on the upper surface of a donut-shaped elastic body having holes through which a plurality of screws 62 are inserted. The present invention is applicable.

  In the parallel optical transmission apparatus 10 according to the above-described embodiment, the transmission optical module 3 having a function of converting an electrical signal into an optical signal is used, but for reception having a function of converting an optical signal into an electrical signal. The present invention can also be applied to a parallel optical transmission apparatus using the optical module. In this configuration, a TIA (Transimpedance Amplifier) function that uses a photodiode array having a plurality of photodiodes as a plurality of optical elements, converts the output current of each photodiode into a voltage and amplifies it instead of the driver IC 33 as an electrical element. An amplification IC provided with

  When the electric pluggable socket 1 is made of a material that propagates noise, such as metal, the spacer 40 is made of an insulating elastic material to prevent noise from the heat sink 20 from propagating to the substrate. can do.

  In the parallel optical transmission device 10 according to the above-described embodiment, the optical connector 4 is bent by 90 degrees light emitted from the optical elements 32 in the vertical direction, and a plurality of optical connectors 4 are held by the connector unit 42. Although the optical component 60 optically coupled to each end face of the optical fiber is used, the present invention is not limited to such a configuration. The connector portion 42 of the optical connector 4 is structured to hold a plurality of optical fibers each having a 90-degree bent portion, and light emitted in a perpendicular direction from each optical element 32 is coupled to the end face of each optical fiber. The present invention is also applicable to the configured parallel optical transmission apparatus.

  FIG. 9 shows an example of the cross-sectional structure of the spacer 40. FIG. 9A shows a rectangular cross-sectional shape. FIG. 9B shows a cross section having a trapezoidal shape. In FIG. 9C, rectangular or triangular dots or stripes are formed on a rectangular base. Here, the height h1 is set to a value slightly lower than the protruding height of the optical module 35 in the case where the height h1 is created with a design value that does not cause tolerances, in consideration of the contraction height at the time of pressing. In the case of FIG. 9B and FIG. 9C, the repulsive force can be adjusted according to the pressing distance, so that damage due to excessive pressing can be prevented.

  FIG. 10 shows an example of the spacer 40. Here, the spacers 40 are made of different materials for the screwing portion 81 and the flat portion 80 in order to alleviate the difference in local stress. For example, when warping of the screwing portion 81 occurs, an elastic material that is harder than the flat portion 80 is selected for the screwing portion 81. The portion for changing the material of the spacer and the material thereof are appropriately selected in consideration of the deformation of the electric pluggable socket 1 and the pressing member 2.

DESCRIPTION OF SYMBOLS 1: Electric pluggable socket 2: Pressing member 3: Optical module 4: Optical connector 5: Electric board 10: Parallel optical transmission device 11: Bottom wall part 12: Perimeter wall part 13: Connection terminal part 14: Module accommodation recessed part 20: Heat sink 32 : Optical element (VCSEL)
33: IC
34: Module substrate 35: Module cover 41: Tape fiber 42: Connector part 40: Spacer 50: Step 60: Optical component 62: Screw 70: Protrusion 71: Base part 80: Flat part 81: Screwing part

Claims (8)

An electric pluggable socket having a bottom wall portion on which a plurality of electrical connection terminal portions are arranged, a peripheral wall portion forming a module housing recess, and fixed on an electric board;
Light that is detachably mounted in the module housing recess, and is electrically connected to the electrical board via the connection terminal portion of the socket when mounted, and converts an electrical signal into an optical signal or an optical signal into an electrical signal. Module,
A pressing member that presses the optical module and the socket from above to apply a pressing force and is detachably fixed to the peripheral wall portion;
An optical connector for transmitting the optical signal in parallel with the optical module,
A parallel optical transmission device, wherein a spacer having a thickness to fill a step formed between the upper surface of the peripheral wall portion and the upper surface of the optical module is provided between the socket and the pressing member.   The parallel optical transmission device according to claim 1, wherein the plurality of electrical connection terminal portions are electrically connected when receiving a predetermined pressing force.   The parallel optical transmission apparatus according to claim 1, wherein the spacer is made of an elastic material.   The parallel optical transmission device according to claim 1, wherein the spacer has a thickness larger than the step.   5. The parallel optical transmission apparatus according to claim 1, wherein the spacer is a sheet-like elastic body disposed on the entire upper surface of the peripheral wall portion of the socket. 6. 6. The parallel optical transmission device according to claim 1, wherein the spacer is made of rubber containing metal fibers or rubber containing a ceramic filer . 7. 7. The parallel light according to claim 1, wherein a part of the peripheral wall portion of the socket on the spacer side is formed of an alloy of copper and tungsten. Transmission equipment.   The said spacer is formed from the some material from which elastic force differs, and is arrange | positioned according to the pressing force between the said pressing member and the said surrounding wall part, The any one of Claim 1 thru | or 7 characterized by the above-mentioned. The parallel optical transmission device according to one item.

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