JP4978213B2 - Optical transceiver - Google Patents

Description

  The present invention relates to a pluggable optical transceiver having a transmission assembly (TOSA) and a reception assembly (ROSA).

  12A and 12B are diagrams illustrating a configuration example of a pluggable optical transceiver. FIG. 12A is a perspective view of the pluggable optical transceiver, and FIG. 12B is a diagram illustrating the optical transceiver of FIG. It is a perspective view when accommodated in a made cage. In FIG. 12, 1 is a pluggable optical transceiver (hereinafter simply referred to as an optical transceiver), 2 is a cage, 2a is an opening, 2b is an electrical connector, 2c is a stud pin, 2d is a fin, and 10a and 10b are optical receptacles. , 11 is a bale, 14 is a tab plate, and 23 is a cover.

  The optical transceiver 1 is used by being inserted into a metal cage 2 provided on a circuit board of a host device (not shown) (FIG. 12B). A plurality of stud pins 2c are formed on the lower surface of the cage 2, and the stud pins 2c are soldered to the circuit board of the host device. At this time, the opening 2a of the cage 2 is exposed from the face panel of the host device.

  An electrical connector 2b is provided at the back end of the cage 2 in a state of being connected to a wiring pattern on the circuit board. By inserting the optical transceiver 1 into the cage 2, the electrical plug formed at the back end of the optical transceiver 1 is engaged with the electrical connector 2b, and various signals and power can be transmitted and received. Thereby, communication between the optical transceiver 1 and the host device is established. Further, by making the electrical plug hot-pluggable, a hot-pluggable transceiver that inserts and removes the optical transceiver 1 into and from the cage 2 while the host device is energized can be provided.

The cage 2 is a metal box that is open at one end. A grounding tab plate 14 is provided on the outer periphery of the optical transceiver 1 so as to protrude from the cover 23.
When the optical transceiver 1 is inserted into the cage 2, the tip of the tab plate 14 is placed in contact with the inner surface of the cage 2. A plurality of fins 2d are provided on the outer periphery of the opening 2a of the cage 2 so as to extend toward the outside of the cage.
In a state in which the cage 2 is mounted on the circuit board of the host device, the fin 2d is in electrical contact with the face panel of the host device and grounded, and the shielding effect of the optical transceiver 1 is enhanced.

  The optical transceiver 1 as described above includes a main body and an OSA (Optical Sub-Assembly) unit. The main body includes a main circuit board, a sub circuit board, a base for holding them, a heat radiating plate and a holding component, and a cover. The OSA unit includes a receptacle member, a tab plate, and a transmitting subassembly (TOSA) inserted into the receptacle, and a receiving subassembly (ROSA). Yes. The optical fiber cable and the optical subassembly are optically coupled via an optical connector, thereby enabling both optical transmission and optical reception.

As such an optical transceiver 1, one having a configuration in which a metallic shield plate is provided to shield electromagnetic waves from openings such as a receptacle member and a cage is known. As an optical connector having a shield structure, for example, Patent Document 1 discloses a shielded optical fiber adapter attached to an opening of a conductive face plate of an electronic device. This optical fiber adapter has a structure in which a conductive plate is embedded in a non-conductive main body, and the conductive plate is provided with an opening for allowing light from the optical fiber to pass therethrough. . The conductive plate protrudes outside the main body and comes into contact with the conductive face plate.
US Patent Publication No. 6193420

  The pluggable optical transceiver 1 as described above has a problem that its resistance to electrostatic discharge (ESD) is not sufficient. That is, when the generated ESD is applied to the optical transceiver 1, an electromagnetic wave enters from the gap of the shield, causing a problem that the circuit of the optical transceiver 1 is adversely affected.

For example, the OSA sleeve is the only part of the optical transceiver 1 that is open to the outside. Even if the entire optical transceiver is to be completely shielded with a metal cover, the sleeve exposed in the optical receptacle must be open to the outside. This is because the optical connector is inserted into the optical receptacle. Therefore, the shield between the outside around the sleeve and the inside of the transceiver must be perfect. However, an electromagnetic wave caused by ESD enters the transceiver from the periphery of the sleeve that is open to the outside, and affects the circuit of the optical transceiver 1.
The adapter of Patent Document 1 merely discloses a configuration including a shield plate between optical fiber connectors, and is not applicable to the optical transceiver of the present application.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an optical transceiver having good ESD tolerance.

  In order to solve the above problems, an optical transceiver according to the present invention is an optical transceiver that is used by being inserted into an opening of a cage mounted on a host system having an opening at one end and an electrical connector at the other end. The optical transceiver includes a receptacle member having an optical receptacle that receives an optical connector, a receiving optical subassembly that is optically coupled to the optical connector and converts the optical signal into an optical signal that propagates through a first optical fiber, A transmission optical subassembly optically coupled to the connector and propagating electrical signals through the second optical fiber; and a metal base mounted with a circuit board connected to the two optical subassemblies and engaged with the receptacle member. I have. A shield member that contacts the receptacle member and the metal base is attached to the two optical subassemblies.

  In addition, the shield member is manufactured by sheet metal processing of a plate-shaped metal plate, and includes two U-shaped portions having a U-shape that matches the outer diameter shape of the two optical subassemblies, and two U-shaped portions. It has a central post formed in between and an outer post formed on both outer sides with two U-shaped portions interposed therebetween. Here, when the major axis direction of each post is the vertical direction, in the optical transceiver, the metal plate forming the central post and the outer post is bent at the lower part of the shield member, and further parallel to the central post after a predetermined distance. Thus, two lower folded portions further bent upward are further provided.

  The two optical subassemblies have a shield member attaching portion for attaching the shield member. The shield member attaching portion is formed as a portion having a small diameter in the axial direction of each of the two optical subassemblies, and the central post and the outer post of the shield member are inserted into the gap formed in the small diameter portion. It is.

  The shield member includes a spring portion that is bent from the center post in a direction opposite to the lower folded portion at the lower portion of the center post, and the spring portion is in contact with the metal base. Further, both outer edges of the two outer posts of the shield member are in contact with the metal base, and the upper edge of the center post is in contact with the tab plate combined with the receptacle member.

ADVANTAGE OF THE INVENTION According to this invention, the optical transceiver provided with favorable ESD tolerance can be provided by attaching the shielding member which contacts a receptacle member and a metal base with respect to an optical subassembly.
The shield member can be easily and reliably imparted with ESD resistance simply by being inserted into the gap formed in the optical subassembly.

  FIG. 1 is an exploded view of an embodiment of an optical transceiver according to the present invention, in which 11 is a bale, 12 is an actuator, 13 is a receptacle member, 14 is a tab plate, 15 is an optical subassembly (OSA), 16 Is a main circuit board, 17 is a sub circuit board, 18 is an insulating film, 20 is a base, 21 is a heat radiating plate, 22 is a holding part, 23 is a cover, 24, 26 and 27 are heat radiating sheets, 25 is a bracket, 28a and 28b , 28c are labels, and 28d is a resin such as a laminate film.

  The optical transceiver 1 includes a main body unit and an OSA unit. The main body includes a main circuit board 16, a sub circuit board 17, a base 20 for holding them, a heat radiating plate 21 and a holding component 22, and a cover 23. The OSA unit includes an optical subassembly (OSA) 15 including a transmission subassembly (TOSA) and a reception subassembly (ROSA).

  The optical receptacle portion includes a resin receptacle member 13, an actuator 12, a bail 11, and a metal tab plate 14. The bale 11 may be made of resin or metal. The bail 11 and the actuator 12 provide a mechanism for releasing the engagement between the optical transceiver 1 and the cage 2 in which the optical transceiver 1 is housed.

  In this example, when the bail 11 is rotated around the protrusion 13d provided on the side surface of the receptacle member 13, the front end of the actuator 12 is pushed downward. The central portion of the actuator 12 is fixed to the receptacle member 13, and the rear end is pushed upward by the movement of the seesaw with this fixed point as a fulcrum. That is, the protrusion provided at the rear end of the actuator 12 is pulled toward the main body side of the transceiver 1 and released from the engagement hole of the cage 2.

  In the description of the optical transceiver 1 of the present embodiment, the side on which the receptacle member 13 is installed in the optical axis direction (long axis direction of the optical transceiver) of the OSA (TOSA / ROSA) 15 corresponding to the Z-axis direction in FIG. Is the front side and the opposite side is the rear side. Also, among the directions orthogonal to the front-rear direction, the X-axis direction in FIG. 1 is the left-right direction, and the Y-axis direction in FIG.

The assembly of the optical subassembly mounted on the receptacle member 13, the tab plate 14, and the receptacle member 13 is called an OSA unit.
FIG. 2 is a perspective view showing a configuration example of an optical subassembly (OSA) incorporated in the OSA unit. The OSA 15 includes a transmission subassembly (TOSA) and a reception subassembly (ROSA). These OSAs 15 each have a coaxial type package.

  In the ROSA, a semiconductor light receiving element (APD; Avalanche Photodiode) or PIN-PD (generally referred to as “PD”) and a preamplifier for amplifying a weak electric signal generated by the PD are mounted. In addition to the semiconductor light emitting element (LD: Laser Diode), a PD for monitoring the emission intensity of the LD or a thermoelectric conversion element (Peltier Device) for adjusting the temperature of the LD is mounted in the TOSA. There is also a case. In addition, when the driving frequency is high (10 GHz or higher), a semiconductor device for LD driving may be included.

  The signal / power supply line from the OSA (TOSA / ROSA) 15 or the signal / power supply line to the OSA 15 is connected via a lead pin 15b provided on the stem 15a at the rear end. It is also common to use a flexible substrate (not shown) instead of the lead pin 15b or in addition to the lead pin 15b.

  A sleeve 15 d is provided at the front end of the OSA 15. When the OSA 15 is set with respect to the receptacle member 13, optical coupling is performed between an element such as a semiconductor laser or a photodiode mounted on the OSA 15 and an optical fiber connected to the optical connector inserted into the receptacle member 13. Is realized.

The OSA (TOSA / ROSA) as described above is composed of a sleeve 101 with a stub, a joint sleeve (J sleeve) 102, and a CAN package 103.
The stub-containing sleeve 101 has a built-in stub, and the stub has an optical fiber at its center, the end surface on the joint sleeve 102 side is polished at an arbitrary angle, and the opposite end surface is physically connected to the ferrule of the optical connector. It is processed into a protruding shape so as to abut. The CAN package 103 is a coaxial package having a PD that receives an optical signal in a ferrule of an optical connector inserted into the sleeve 101 with a stub and converts it into an electrical signal. The joint sleeve 102 connects the stub-containing sleeve 101 and the CAN package 103. Before fixing the stub-containing sleeve 101, the rear end surface of the sleeve is slid on the flat surface at the front end of the joint sleeve 102, thereby providing an optical fiber. And optical alignment between the CAN package 103 and the PD.

  The sleeve 101 with the stub of the OSA 15 is provided with a pair of flanges 15c. An OSA holding portion (holding portion) 15e for holding the OSA 15 is formed in a region between the pair of flanges 15c. The diameter of the flange 15c is, for example, about 5 mmφ, and the diameter of the OSA holding portion 15e is, for example, about 4.2 mmφ. The length of the OSA holding portion 15e in the Z direction is, for example, about 1 to 1.5 mm.

  As described above, the rear end surface of the stub-containing sleeve 101 and the front end surface of the joint sleeve 102 are abutted with each other, optically aligned with XY, and fixed by welding with a YAG laser. With this configuration, a portion having a small diameter is formed between the rear flange of the flange 15c formed on the stub-containing sleeve 101 and the front end surface of the joint sleeve 102. A gap G of about 0.2 mm is formed. The gap G is formed in the joint sleeve 101, and the shield member according to the feature of the present invention is attached to the gap G. A portion to which the shield member is attached is referred to as a shield member attachment portion 15f. The detailed configuration of the shield member and its mounting structure will be described later.

  3 to 5 are diagrams for explaining the configuration of the OSA unit in the optical transceiver according to the embodiment of the present invention. FIG. 3 is an exploded perspective view of the OSA unit as viewed from the bottom. FIG. 4 is an assembled view. FIG. 5 is an exploded perspective view of the OSA unit as seen from the bottom side, and FIG. 5 is a perspective view of the assembled OSA unit as seen from the bottom side.

  The receptacle member 13 is a resin member and has first to third portions 13a to 13c as shown in FIG. The first part 13a is located at the forefront of the optical transceiver 1 and includes an optical receptacle 10 that is two spaces into which optical connectors are inserted. In addition, a projection 13 d serving as the rotation center of the bail 11 is formed on the outer wall of the receptacle member 13.

  On the bottom surface of the first part 13a, a protrusion 13e is formed in the center along the boundary with the second part 13b, and hook-like hooks 13f are formed on both sides. And the protrusion 13e of the said 1st site | part 13a is engaged with the hollow 12j formed in the actuator 12 shown in FIG. 1, and the rotating shaft 12g of the actuator 12 is set to the hook 13f simultaneously. Thereby, the seesaw motion of the actuator 12 around the hook 13f is realized.

  The second portion 13b of the receptacle member 13 has a side wall 13h and a central partition wall 13i, and two cavities 13k for accommodating the OSA (TOSA / ROSA) 15 are formed thereby. The bottoms of these cavities 13k (upper side in FIG. 3) are open, so that the OSA 15 can be set in the cavities 13k.

  The boundary between the second part 13b and the third part 13c is bent in a U shape. A U-shaped rear wall 13q is provided in this portion, and a groove 13j is provided along the U-shaped rear wall 13q. 4 and 5, one of the front side of the pair of flanges 15c included in each OSA (TOSA / ROSA) 15 is set in the groove 13j. Thereby, the position of the OSA 15 with respect to the receptacle member 13 can be fixed. The pair of flanges 15c of the OSA 15 sandwich the surface 141 of the tab plate 14 and the rear wall 13q of the receptacle member 13 together. The configuration of the tab plate 14 will be described later.

  On the side wall 13h of the second portion 13b of the receptacle member 13, a protrusion 13g is formed substantially at the center of the outer surface. The tab plate 14 and the cover 23 can be fixed to the receptacle member 13 by engaging the protrusion 13g with the engagement hole of the tab plate 14 and the engagement hole of the cover 23. The cross-section of the protrusion 13g has a gentle shape on the side where the tab plate 14 and the cover 23 are inserted so that the tab plate 14 and the cover 23 are smoothly engaged. The opposite side has a steep shape so that the cover 23 is not easily detached.

  The third portion 13c of the receptacle member 13 has an upper wall 13l continuous from the upper side of the second portion 13b. Protrusions 13m are provided at both ends of the upper wall 13l, and the base 20 and the receptacle member 13 are engaged by the protrusions 13m.

  The tab plate 14 has a first part 14a and a second part 14b. The first portion 14a has a plurality of fins 14c, 14d, and 14f that surround the receptacle member 13 and expand outward. These fins 14c, 14d, and 14f are in contact with the inner surface of the cage 2 and exhibit a shielding function. Further, among the fins, fins 14d and 14f provided on both sides and above the first portion 14a project partially at the center, and these fins 14d and 14f reliably contact the inner surface of the cage 2. It is like that.

  The tips of the fins 14c, 14d, and 14f are bent in a wave shape so that the bottom of the bent portion is fitted in a groove provided at the boundary between the first portion 13a and the second portion 13b of the receptacle member 13. The fins 14d on both sides of the tab plate 14 have openings, and latch pieces 14e are formed in the openings. Then, the center hole of the latch piece 14 e and the protrusion 13 g of the receptacle member 13 are engaged to fix the tab plate 14 to the receptacle member 13.

  Moreover, the 2nd site | part 14b of the tab board 14 is folded double. In this double-folded portion, the surface 14g that continues to the fin 14f, the surface 14h that is bent substantially at right angles to the surface 14g, and the first portion 14a side of the surface 14h are bent again at a right angle. A surface 14i is formed. The upper wall 13l of the receptacle member 13 is sandwiched between the surface 14g and the surface 14i. As a result, the tab plate 14 is fixed to the receptacle member 13.

  Further, the second portion 14b of the tab plate 14 is further formed with a surface 141 that is bent at a substantially right angle in a direction opposite to the fin 14f. A U-shaped cut 14m is provided on the surface 141, and a latch piece 14k is formed at the back end of the cut 14m. The latch piece 14k corresponds to the notch 13n at the U-shaped back end of the receptacle member 13, and further defines the positions of the tab plate 14 and the receptacle member 13. Further, a spacer portion 14j obtained by bending the tab plate 14 is provided in the center of the surface 14l, that is, between the two U-shaped cuts 14m.

  The width of the U-shaped cut 14m of the tab plate 14 formed by the spacer portion 14j is set slightly smaller than the diameter of the OSA holding portion 15e provided in the OSA 15. Thus, after the OSA 15 is set on the tab plate 14 while applying a pressing force, the OSA 15 does not easily fall off the tab plate 14.

  In the receptacle member 13, a column holder 13 r is formed at a position facing the spacer portion 14 j of the tab plate 14, that is, a position between the central partition wall 13 i and the spacer portion 14 j. By inserting a post 20d of the base 20 (described later with reference to FIG. 10) into the column holder 13r, both members are fixed in cooperation with the engaging action of the projection 13g of the receptacle member 13 and the base 20 described above. Is done.

  The tab plate 14 is formed, for example, by cutting, drilling, bending, drawing, or the like on a single metal plate made of stainless steel having a thickness of 0.15 mm. Here, since welding, adhesion, cut-out processing, and the like are not used, it is possible to reduce the component unit price.

  As shown in FIG. 4, the OSA (TOSA / ROSA) 15 is accommodated in a cavity 13 k included in the receptacle member 13. At this time, the surface 141 of the tab plate 14 and the rear wall 13q of the receptacle member 13 are sandwiched together by the pair of flanges 15c included in the OSA 15 as described above.

  When the OSA 15 is set with respect to the receptacle member 13, the sleeve 15d provided at the tip of the OSA 15 protrudes into the optical receptacle 10 at the first portion 13a. Thereby, optical coupling is realized between an element such as a semiconductor laser or a photodiode mounted on the TOSA 15 / ROSA 16 and an optical fiber connected to the optical connector inserted in the optical receptacle 10. The geometric dimension of the optical receptacle 10 and the position of the sleeve 15d are strictly determined based on the standard of the optical connector.

  Further, the sleeve 15d and the flange portion 15c are made of metal, and the latch piece 14k is provided in the U-shaped cut of the tab plate 14, thereby ensuring electrical continuity between the tab plate 14 and the sleeve 15d. In addition, since the tab plate 14 is grounded via the cage 2 outside the optical transceiver 1, the optical transceiver 1 having this structure can reliably ground the sleeve 15d of the OSA 15.

  The longitudinal position of the OSA 15 with respect to the optical transceiver 1 is defined by the flange 15c sandwiching the surface 14l of the tab plate 14 and the rear wall 13q of the receptacle member 13 together. Further, the position of the OSA 15 in the left-right direction with respect to the optical transceiver 1 is defined by a U-shaped rear wall 13q.

  The vertical position of the OSA 15 with respect to the optical transceiver 1 is roughly determined by a U-shaped cut 14m formed in the tab plate 14. Here, as described above, the dimensions of the two U-shaped cuts 14m formed in the tab plate 14 are set to be slightly narrower than the diameter D of the OSA holding portions 15e and 16e. Accordingly, the vertical position of the OSA 15 is substantially determined by the U-shaped cut 14m of the tab plate 14.

  With the above configuration, a predetermined shield member is attached to the shield member attachment portion 15f of the OSA 15 in the optical transceiver 1. 6A and 6B are perspective views showing a configuration example of a shield member used in the optical transceiver of the present invention, in which FIG. 6A is a view of the shield member as viewed from the upper front side, and FIG. 6B is a rear view of the shield member. It is the figure seen from diagonally downward. The vertical direction of the U-shaped portion 31 in FIG. 6 matches the installation state of the optical transceiver 1 (the state when it is incorporated in a data link such as a host), and here, XYZ (left / right / up / down / front / rear direction) is changed. Consider the above installation conditions.

  The shield member 30 is made of sheet metal, and has two U-shaped portions 31 for attachment to the shield member attachment portion 15 f of the OSA (TOSA / ROSA) 15. The U-shape formed by the U-shaped portion 31 has a convex portion on the lower side and is open on the upper side. The U-shaped opening is wide open to avoid YAG welding.

  A central post 32 is formed between the two U-shaped portions 31. The center post 32 has an upper end portion folded back to the front side to form a center post folded portion 32a. Here, an upper edge of a portion where the central post 32 is folded is referred to as an edge A.

  Two outer posts 33 are formed on the lateral outer sides of the two U-shaped portions 31. The two outer posts 33 have their upper end portions folded back to the front side to form an outer post folded portion 33a. And each outer post folding | returning part 33a is mutually connected in the front-end | tip part, and forms the connection part 33b. The upper end edge of the connecting portion 33b is configured to substantially coincide with the position of the U-shaped lower top portion of the U-shaped portion 31 in the height direction (vertical direction). Edges on both outer sides of the outer post 33 are referred to as edge B.

  A spring portion 34 that is bent and protrudes behind the shield member 30 is formed at the lower portion of the center post 32. The member connected to the center post 32 and the outer post 33 is bent approximately 90 ° to the front side at the position of the lower end of the shield member 30, and further connected at a predetermined distance from the bent position past the connecting portion 33b. Is bent approximately 90 ° upward so as to be held, and becomes substantially parallel to the central post 32. The portion bent upward is referred to as a lower folded portion 35. Two lower folded portions 35 are provided on both lateral sides of the spring portion 34, and each lower folded portion 35 has three claw portions 35a.

  FIGS. 7 to 9 are diagrams for explaining a structure for attaching the shield member to the OSA unit, and is a view of the unit with the circuit board attached to the base attached to the OSA unit of the optical transceiver as viewed from the bottom side. is there. FIG. 7 is a diagram showing a state of the unit before the shield member 30 is attached, and the shield member 30 is attached at a position S in FIG. At the position S, the shield member attaching portion 15f of the OSA 15 exists.

  FIG. 8 shows a state when the shield member 30 is attached to the OSA unit. As shown in FIG. 8, the shield member 30 is attached to the shield member attachment portion 15 f of the OSA 15 from the bottom surface side of the OSA unit to which the OSA (TOSA / ROSA) 15 is attached. At this time, the central post 32 and the outer post 33 (see FIG. 6) of the shield member 30 are respectively inserted into the gap G formed in the shield member attachment portion 15f of the OSA 15, and the U-shaped of the shield member 30 is formed. The shape part 31 is adapted to the outer peripheral shape of the shield member holding part 15 f of the OSA 15. At this time, the edge A of the central post contacts the surface 14 i of the tab plate, and the edges B on both outer sides of the outer post 33 contact the wall surface of the base 20.

  FIG. 9 shows a state where the shield member is attached to the OSA unit. With the shield member 30 attached to the OSA unit, the two lower folded portions 35 of the shield member 30 are sandwiched between the rear walls 13q of the receptacle member 13. Here, the claw portion 35a located on the outermost side in the left-right direction of the lower folded portion 32 abuts against the rear wall 13q located further outside. Then, the edge B of the outer post 33 abuts against the side wall 20b (not shown) of the base, whereby the position of the shield member 30 with respect to the base 20 is determined, and at the same time, the shield member 30 and the base 20 are electrically reliably connected. Since the contact is made, the inside of the optical transceiver 1 can be shielded.

  FIG. 10 is a perspective view of a state in which the base 20 is attached to the OSA unit configured as described above, as viewed from the bottom side. In a state where the main circuit board 16 and the OSA unit 6 are temporarily fixed, the main circuit board 16 is pressed against the base 20. Here, the protrusion 13m provided on the side surface of the OSA unit 6 (actually the side surface of the receptacle member 13) engages with the opening 20a of the base side wall 20b. Even after the receptacle member 13 and the tab plate 14 are assembled, the protrusion 13m is exposed to the side surface of the assembly, and thus can be engaged with the opening 20a of the base. Further, simultaneously with the engagement between the protrusion 13m and the base opening 20a, the post 20d at the front end of the base 20 engages with a column receiver 13r provided at the center of the receptacle member 13.

  As described above, the OSA unit 6 and the base 20 are fixed at three locations (two sidewalls and one front end) by the two protrusions 13m and the one pillar support 13r. In the protrusion 13m, the OSA unit 6 side is convex and the base 20 side is concave, and in the pillar support 13r, the OSA unit 6 side is concave and the base 20 side is convex.

  When the OSA 15 is pressed upward from the U-shaped open side of the receptacle member 13 by the tip 20c of the base 20, the vertical position thereof is determined. At this time, the edge A (see FIG. 6) of the central post 32 of the shield member 30 contacts the surface 14 i of the tab plate, and the spring portion 34 of the shield member 30 contacts the bottom surface of the base 20. Thereby, the contact of the up-down direction of the shield member 30 is ensured. Further, contact between the inner surface of the side wall of the base 20 and the edge B of the outer post 33 of the shield member 30 ensures a contact in the left-right direction. Thereby, the shield function by the shield member 30 is made sufficient.

FIG. 11 is a view showing a state where the main circuit board and the sub circuit board are attached to the base attached to the OSA unit of the optical transceiver, and is a perspective view of the unit including the base 20 as seen from the upper surface side.
On the main circuit board 16, an electronic circuit including the IC 16b is configured. As this electronic circuit, an LD driving circuit for driving an LD, or a circuit for processing an electric signal amplified in the ROSA and extracting a clock and data in the signal, or the like is used. When an APD is used as a receiving device, a circuit that generates and controls a bias voltage necessary for the APD is used.

  Further, when a thermoelectric conversion element (Peltier Device) for adjusting the temperature of the LD is mounted in the TOSA, it is necessary to include a control circuit for the thermoelectric conversion element. In addition, when other additional functions such as a CPU or a memory for controlling these circuits in general are added, there is a case where a single circuit board cannot fit. In this case, a circuit that does not handle a high-speed signal, such as a circuit that generates and controls the bias voltage of the APD or a circuit that controls the heat transfer conversion element, is mounted on another additional board (sub circuit board 17). .

  The sub circuit board 17 is connected from the side of the main circuit board 16 via the FPC board 17d. The FPC board 17d is soldered to the main circuit board 16. The sub circuit board 17 is overlapped with the main circuit board 16 by folding the FPC board 17d. In addition, an insulating film 18 is inserted into the back surface of the sub circuit board 17 in order to avoid the back surface of the sub circuit board 17 from being in electrical contact with the heat sink 21.

At the rear end of the main circuit board 16, an electrical plug 16a is formed. Then, the connector 2b electrically connected to the circuit board of the host system in the cage 2 is engaged with the electric plug 16a. As a result, the electronic circuit of the host system and the circuit on the main circuit board 16 in the optical transceiver 1 are electrically connected.
At the same time, by setting the electrode shape of the electric plug 16a to a predetermined one, it is possible to realize a so-called hot plug function in which the electric plug 16a and the connector can be inserted and removed while the host system is energized.

  In the optical transceiver 1 of this embodiment, the electrical circuit on the main circuit board 16 and the OSA 15 are electrically connected by the lead pin 15b included in the OSA 15. On the front side of the main circuit board 16, an electrode 16c for connecting to the lead pin 15b of the OSA 15 is formed. A flexible substrate can also be used for connection between the OSA 15 and the substrate.

When the operating frequency of the optical transceiver 1 exceeds 1 GHz, the connection between the OSA 15 and the circuit board is performed by impedance matching connection means. Even in the case of connection using an FPC board, it is preferable to achieve impedance matching by using wiring on the FPC board as a microstrip line and a coplanar line. Alternatively, it is preferable to adopt a configuration in which the length of the connecting means is made as short as possible to avoid the influence as much as possible even when impedance mismatch occurs.
The base 20 covers the lower surface of the OSA 15 and mounts the main circuit board 16. The base 20 is also obtained by cutting / bending a sheet of metal such as iron or stainless steel, and has a cost-effective structure. That is, the base 20 forms a space that opens upward.

  A heat sink can be further assembled to the base 20 attached to the OSA unit 6. Here, in order to increase the heat radiation efficiency from the IC etc. on the main circuit board 16, the heat radiation sheet 21 (FIG. 1) is attached directly to the upper surface of the IC or by interposing a resin material such as silicone. .

1 is an exploded view of an embodiment of an optical transceiver according to the present invention. FIG. It is a perspective view which shows the structural example of the optical subassembly (OSA) integrated in an OSA unit unit. It is a figure for demonstrating the structure of the OSA unit in one Embodiment of the optical transceiver which concerns on this invention, and is the disassembled perspective view which looked at the OSA unit from the bottom face side. It is a figure for demonstrating the structure of the OSA unit in one Embodiment of the optical transceiver which concerns on this invention, and is the exploded perspective view which looked at the assembled OSA unit from the bottom face side. It is a figure for demonstrating the structure of the OSA unit in one Embodiment of the optical transceiver which concerns on this invention, and is the perspective view which looked at the assembled OSA unit from the bottom face side. It is a perspective view which shows the structural example of the shield member used for the optical transceiver of this invention. It is the figure which looked at the state of the OSA unit before attaching a shield member from the bottom face side. It is a figure for demonstrating the state when attaching a shield member to an OSA unit. It is the figure which looked at the state which attached the shield member to the OSA unit from the bottom face side. It is the perspective view which looked at a mode that a base is attached to the assembled OSA unit from the bottom face side. It is a figure which shows the state which attached the main circuit board and the subcircuit board | substrate with respect to the base attached to the OSA unit of the optical transceiver. It is a figure which shows the structural example of a pluggable optical transceiver.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Optical transceiver, 2 ... Cage, 2a ... Opening port, 2b ... Electrical connector, 2c ... Stud pin, 2d ... Fin, 6 ... OSA unit, 10a, 10b ... Optical receptacle, 11 ... Bale, 12 ... Actuator, 12g ... Rotating shaft, 13 ... Receptacle member, 13a ... First part, 13b ... Second part, 13c ... Third part, 13d ... Projection, 13f ... Projection, 13f ... Hook, 13g ... Projection, 13h ... Side wall, 13i ... Central section Wall, 13j ... groove, 13k ... hollow, 13l ... upper wall, 13m ... projection, 13n ... cut, 13q ... rear wall, 13r ... post rest, 14 ... tab plate, 14a ... site, 14b ... site, 14c, 14d, 14f ... Fin, 14e ... Latch piece, 14g ... Face, 14h ... Face, 14i ... Face, 14j ... Spacer part, 14k ... Latch piece, 14l ... Face, 14m ... U 15 ... OSA, 15a ... stem, 15b ... lead pin, 15c ... flange, 15d ... sleeve, 15e ... OSA holding part, 15f ... shield member attaching part, 16 ... main circuit board, 16a ... electric plug, 16b ... IC 16c, 16d ... electrodes, 17 ... sub circuit board, 17d ... FPC board, 18 ... insulating film, 20 ... base, 20a ... opening, 20b ... base side wall, 20c ... tip, 20d ... post, 21 ... heat sink, 21a, 21b, 21c ... bent piece, 22 ... holding part, 23 ... cover, 24, 26, 27 ... heat dissipation sheet, 25 ... bracket, 28a, 28b, 28c ... label, 28d ... resin, 30 ... shield member, 31 ... U-shaped portion 31, 32 ... center post, 33 ... outer post, 33a ... outer post folded portion, 33b ... connection portion, 3 ... spring part, 35 ... lower folded portion, 35a ... claw portion, 101 ... stub containing the sleeve, 102 ... joint sleeve, 103 ... CAN package.

Claims (4)

An optical transceiver used by being inserted into the opening of a cage mounted on a host system having an opening at one end and an electrical connector at the other end,
A receptacle member having an optical receptacle for receiving the optical connector;
A receiving optical subassembly that optically couples to the optical connector and converts the optical signal propagating through the first optical fiber and an electrical signal;
A transmitting optical assembly optically coupled to the optical connector and converting an electrical signal into an optical signal propagating through a second optical fiber;
A circuit board connected to the two optical subassemblies, and a metal base engaged with the receptacle member;
A shield member that contacts the receptacle member and the metal base is attached to the two optical subassemblies ;
The shield member is manufactured by cutting and bending a plate-shaped metal plate, and has two U-shaped portions having a U-shape that matches the outer diameter shape of the two optical subassemblies, and the two A central post formed between the U-shaped portions and outer posts formed on both outer sides of the two U-shaped portions;
Further, when the major axis direction of each post is the vertical direction, the metal plate forming the central post and the outer post is bent at the lower part of the shield member, and further parallel to the central post after a predetermined distance. optical transceiver, wherein Rukoto includes a lower folded portion of the two locations so as to become is further bent upward. The two optical subassemblies each include a shield member attaching portion for attaching the shield member, and the shield member attaching portion is formed as a portion having a small diameter in the axial direction of each of the two optical subassemblies. is, optical transceiver according to claim 1, wherein the small gap formed in a portion of the diameter, characterized in that it is inserted the center post and the outer post. The shield member includes a spring portion that is projected from the center post in a direction opposite to the lower folded portion at the lower portion of the center post, and the spring portion is in contact with the metal base. The optical transceiver according to claim 1 . The outer edges of the two outer posts of the shield member abut against a predetermined wall surface of the metal base, and the edge of the upper end of the central post is the wall surface of the tab plate combined with the receptacle member The optical transceiver according to claim 1 , wherein the optical transceiver is in contact with the optical transceiver.

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