JP2011249727A - Optical transceiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical transceiver having excellent EMI shield characteristics.SOLUTION: An optical transceiver comprises an optical reception sub-assembly 14, an optical transmission sub-assembly 12, and a housing 16. The optical reception sub-assembly 14 and the optical transmission sub-assembly 12 have a case defining an outer surface around an axial line extending toward a first direction. The case of at least one of the optical reception sub-assembly and the optical transmission sub-assembly is made of resin. The optical transceiver further comprises a metal shield member 18 that is provided so as to cover an outer surface of the at least one optical sub-assembly. The housing 16 includes two metal surfaces facing each other in a second direction that is orthogonal to the first direction. The shield member includes two contact surfaces in contact with two surfaces of the housing, and a portion that urges the two contact surfaces against the two surfaces of the housing.

Description

  The present invention relates to an optical transceiver.

  An optical transceiver generally includes an optical transmission subassembly, an optical reception subassembly, and a housing. The optical transmission subassembly converts an electrical signal into an optical signal and outputs the optical signal. The optical receiving subassembly converts an optical signal into an electrical signal and outputs the electrical signal. The housing is provided so as to cover the optical transmission subassembly and the optical reception subassembly. Such optical transceivers require countermeasures against electromagnetic interference (EMI).

  For example, in the optical transceiver described in Patent Document 1, leakage of electromagnetic waves is suppressed by providing a metal plate in the gap between the optical transmission subassembly and the optical reception subassembly.

US Pat. No. 6,609,838

  In the optical transceiver, a case that defines the outline of the optical transmission subassembly and the optical reception subassembly may be made of resin. In such cases, even more EMI shielding may be required.

  An object of the present invention is to provide an optical transceiver excellent in EMI shielding performance.

  An optical transceiver according to an aspect of the present invention includes an optical reception subassembly, an optical transmission subassembly, and a housing. The optical receiving subassembly converts the optical signal into an electrical signal and outputs the electrical signal. The optical transmission subassembly converts an electrical signal into an optical signal and outputs the optical signal. The housing is provided so as to cover the optical reception subassembly and the optical transmission subassembly. The optical receiving subassembly and the optical transmitting subassembly have a case that defines an outer peripheral surface around an axis extending in the first direction. The case of at least one of the optical receiving subassembly and the optical transmitting subassembly is made of resin. The optical transceiver further includes a metal shield member provided so as to cover the outer peripheral surface of at least one of the optical subassemblies. The housing includes two metal surfaces facing each other in a second direction orthogonal to the first direction. The shield member includes two contact surfaces that contact the two surfaces of the housing, and a portion that urges the two contact surfaces against the two surfaces of the housing.

  According to this optical transceiver, since the shield member is provided on the outer periphery of the resin case, crosstalk between the optical reception subassembly and the optical transmission subassembly is suppressed. Further, since the shield member is biased against the metal surface of the casing, the connection of the shield member to the frame ground is ensured reliably. Therefore, this optical transceiver is excellent in EMI shielding performance.

  In one embodiment, the case of the optical receiving subassembly may be made of resin.

  In one embodiment, the outer peripheral surface of the case of at least one of the optical subassemblies includes one protrusion, includes two flat portions facing each other in a direction orthogonal to the first direction, and the shield member Are formed with holes into which the protrusions are fitted, and the shield member may have two flat portions in contact with the two flat portions of the outer peripheral surface of the case. According to this aspect, the position of the shield member relative to the outer peripheral surface of the case is uniquely determined, and the shield member is prevented from rotating with respect to the outer peripheral surface of the case even if the portion of the shield member described above is deformed. Is done.

  In one embodiment, in a state before the shield member is attached to the outer peripheral surface of the case, the distance between the two flat portions of the outer peripheral surface of the case is larger than the distance between the two flat portions of the shield member. Also good. According to this aspect, since the case can be held between the two flat portions of the shield member, the rotational movement of the shield member relative to the outer peripheral surface of the case is more reliably prevented.

  As described above, according to the present invention, an optical transceiver excellent in EMI shielding performance is provided.

It is a perspective view of the optical transceiver concerning one embodiment. It is a perspective view which removes a case and shows an optical transceiver concerning one embodiment. 1 is a perspective view of an optical transmission subassembly according to one embodiment. FIG. It is a perspective view of the optical receiving subassembly and shield member concerning one embodiment. It is the top view which looked at the optical receiving subassembly and shield member concerning one embodiment from back. It is a perspective view of the shield member concerning one embodiment. It is the perspective view which looked at the optical receiving subassembly and shield member concerning one embodiment from another direction. It is a perspective view which removes a case and an optical transmission subassembly, and shows a part of optical transceiver concerning one embodiment. 1 is a perspective view showing a part of an optical transceiver according to an embodiment with a case, a frame, and an optical transmission subassembly removed. FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the central axis direction of the case of the optical transmission subassembly and the optical reception subassembly may be referred to as the front-rear direction or the first direction (X direction). The direction in which the optical transmission subassembly and the optical reception subassembly are arranged may be referred to as a width direction or a third direction (Y direction). In addition, a direction orthogonal to the first direction and the third direction may be referred to as a vertical direction or a second direction (Z direction).

  FIG. 1 is a perspective view of an optical transceiver according to an embodiment. FIG. 2 is a perspective view showing an optical transceiver according to an embodiment with a case removed. The optical transceiver 10 shown in FIGS. 1 and 2 is mounted on a host system, and is coupled to an external optical connector plug to convert an optical signal from the optical connector plug into an electrical signal, and the biographical signal is converted into the host system. To provide. Further, the optical transceiver 10 converts an electrical signal from the host system into an optical signal and applies the optical signal to the optical connector plug.

  As shown in FIGS. 1 and 2, the optical transceiver 10 includes an optical transmission subassembly (TOSA) 12, an optical reception subassembly (ROSA) 14, a housing 16, and a shield member 18. In addition, the optical transceiver 10 may include a circuit board 20.

  FIG. 3 is a perspective view of the TOSA 12. The TOSA 12 converts an electrical signal into an optical signal and outputs the optical signal. The TOSA 12 has a case 12a. The case 12a is a substantially cylindrical member extending along the central axis X1 extending in the first direction. The case 12a houses a semiconductor laser therein. In this example, the case 12a is made of metal.

  The TOSA 12 can also include a sleeve 12b. The sleeve 12b is a cylindrical portion and accommodates a ferrule attached to the tip of the optical connector plug in its inner hole. The sleeve 12b optically couples the optical fiber in the ferrule and the TOSA 12 semiconductor laser.

  The case 12a of the TOSA 12 may include a stem 12c at the rear end. The stem 12c is provided along a plane that intersects the axis X1. A plurality of lead pins are provided on the stem 12c. The flexible printed circuit board 12d can be joined to these lead pins. The flexible printed circuit board 12 d can also be bonded to the front end of the circuit board 20.

  FIG. 4 is a perspective view of an optical receiving subassembly and a shield member according to an embodiment. FIG. 5 is a plan view of the optical receiving subassembly and the shield member according to the embodiment as seen from the rear. FIG. 6 is a perspective view of a shield member according to an embodiment. FIG. 7 is a perspective view of the optical receiving subassembly and the shield member according to the embodiment as seen from different directions.

  The ROSA 14 converts an optical signal into an electrical signal and outputs the electrical signal. The ROSA 14 has a case 14a. As shown in FIGS. 4, 5, and 7, the case 14 a is a substantially cylindrical member that extends along the central axis X <b> 2 that extends in the first direction (X direction). The case 14a houses a photodiode therein. In this example, the case 14a is made of resin.

  ROSA 14 may also include a sleeve 14b. The sleeve 14b is a cylindrical portion, and accommodates a ferrule attached to the tip of the optical connector plug in its inner hole. The sleeve 14b optically couples the optical fiber in the ferrule and the ROSA 14 photodiode.

  The case 14a of the ROSA 14 may include a stem 14c at the rear end. The stem 14c is provided along a plane that intersects the axis X2. The stem 14c is provided with a plurality of lead pins. The flexible printed circuit board 14d can be joined to these lead pins. The flexible printed board 14 d is also bonded to the front end of the circuit board 20.

  The case 14a of the ROSA 14 defines an outer peripheral surface 14e around the axis X2. The outer peripheral surface 14e can include a flat surface portion 14f extending in the first direction. In this example, the outer peripheral surface 14e includes four plane portions 14f. Four plane parts 14f constitute a pair including two plane parts. The two flat portions 14f in one pair face each other in a direction orthogonal to the first direction. Further, the outer peripheral surface 14e is provided with a protrusion 14g raised from the surrounding surface.

  As shown in FIGS. 4, 5, and 7, the shield member 18 is provided so as to cover the outer peripheral surface 14e. The shield member 18 is a metal member, for example, a member manufactured by sheet metal processing.

  As shown in FIG. 6, the shield member 18 includes two contact surfaces 18a. The two contact surfaces 18a oppose each other in the second direction (Z direction). The shield member 18 includes two support portions 18b. The contact surface 18a and the support portion 18b are configured to protrude from other portions of the shield member 18 with respect to the outer peripheral surface 14e.

  Further, the shield member 18 may have a flat portion 18c. In this example, the shield member 18 includes four flat portions 18c. The four plane portions 18c constitute a pair including two plane portions. The two flat portions 18c in one pair face each other in a direction orthogonal to the first direction. In the optical transceiver 10, as shown in FIG. 5, the shield member 18 is attached to the outer peripheral surface 14e of the case 14a so that the flat surface portion 18c contacts the corresponding flat surface portion 14f.

  As shown in FIG. 6, one end of one contact surface 18a of the two contact surfaces 18a is connected to the adjacent plane portion 18c among the two plane portions 18c opposed in the second direction. The other end of the one contact surface 18a is connected to one end of the adjacent one of the two support portions 18b. The other end of one support portion 18b is connected to a flat portion 18c existing between the two support portions 18b.

  One end of the other contact surface 18a is connected to the adjacent flat surface portion 18c among the two flat surface portions 18c facing each other in the second direction. The other end of the other contact surface 18a is connected to one end of the other support portion 18b adjacent to the other of the two support portions 18b. The other end of the other support portion 18b is connected to a plane portion 18c existing between the two support portions 18b.

  The two support portions 18b have elasticity or flexibility that deforms when the two contact surfaces 18a come into contact with other surfaces. Thereby, when the two contact surfaces 18a contact another surface, the support portion 18b biases the two contact surfaces 18a against the other surfaces.

  Moreover, as shown in FIG. 6, the shield member 18 may have a hole 18d. As shown in FIG. 7, the shield member 18 can be attached to the outer peripheral surface 14e of the case 14a so that the projection 14g fits into the hole 18d.

  With this configuration, the position of the shield member 18 with respect to the outer peripheral surface 14e of the case 14a is uniquely determined. Further, even if the support portion 18b of the shield member 18 is deformed, the shield member 18 is prevented from rotating with respect to the outer peripheral surface 14e of the case 14a.

  In one embodiment, in a state before being attached to the case 14a, the distance between the two plane portions 14f constituting the pair may be larger than the distance between the two plane portions 18c in the corresponding pair. Thereby, the force which clamps case 14a between the plane parts 18c which comprise a pair is heightened. As a result, the rotational movement of the shield member 18 relative to the outer peripheral surface 14e of the case 14a is more reliably prevented.

  Please refer to FIG. 1 and FIG. 2 again. As illustrated in FIG. 2, the casing 16 is mounted so as to cover the TOSA 12 and the ROSA 14 to which the shield member 18 is mounted. FIG. 8 is a perspective view showing a part of the optical transceiver according to the embodiment with the case and the optical transmission subassembly removed. FIG. 9 is a perspective view showing a part of the optical transceiver according to the embodiment with a case, a frame, and an optical transmission subassembly removed. As shown in FIGS. 1, 2, 8, and 9, the housing 16 may include a frame 22, an optical receptacle 24, a conductive member 26, and a case 28.

  The frame 22 is a metal member configured by sheet metal processing, for example. The frame 22 includes a bottom surface portion 22a extending in a first direction (X direction) and a second direction (Y direction), and side wall portions 22b raised from both edges of the bottom surface portion 22a in the second direction. May be included. The frame 22 has the TOSA 12 and the ROSA 14 mounted on the front end portion of the bottom surface thereof. On the frame 22, the TOSA 12 and the ROSA 14 are mounted so as to be aligned in the third direction. Further, the circuit board 20 can be mounted on the frame 22 behind the TOSA 12 and the ROSA 14.

  The optical receptacle 24 is attached to the front end of the frame 22. The optical receptacle 24 defines two spaces extending in the first direction. In one of these two spaces, a sleeve 12b of TOSA 12 is inserted. Further, the sleeve 14b of the ROSA 14 is inserted into the other of the two spaces. The optical receptacle 24 receives an optical connector plug from the outside in the space. Thereby, the sleeve 12b of the TOSA 12 and the ferrule of the optical connector plug are coupled in the one space. Further, the sleeve 14b of the ROSA 14 and the ferrule of the optical connector plug are coupled in the other space.

  The conductive member 26 is, for example, a metal member formed by sheet metal processing. The conductive member 26 is attached to the optical receptacle 24 along the outer peripheral surface of the optical receptacle 24.

  In this example, the optical receptacle 24 has a wall facing the upper surface of the front end portion of the bottom surface 22 a of the frame 22. The conductive member 26 provided along the wall of the optical receptacle 24 provides a lower surface 26 a that faces the upper surface of the front end portion of the bottom surface portion 22 a of the frame 22. Therefore, the lower surface 26 a of the conductive member 26 and the upper surface of the bottom surface portion 22 a of the frame 22 face each other in the second direction with the TOSA 12 and the ROSA 14 interposed therebetween.

  In the optical transceiver 10, the case 28 is provided so as to cover the TOSA 12, the ROSA 14, the circuit board 20, and the frame 22. The case 28 is a substantially rectangular tube-shaped metal member opened at the front end and the rear end. The case 28 is engaged with the optical receptacle 24 at the front end portion thereof. In the housing 16, the frame 24, the conductive member 26, and the case 28 are electrically connected to each other.

  In the optical transceiver 10, as shown in FIG. 2, the shield member 18 attached to the case 14 a of the ROSA 14 is interposed between the TOSA 12 and the ROSA 14. Therefore, crosstalk between TOSA 12 and ROSA 14 is prevented.

  Further, in the housing 16, one of the contact surfaces 18 a of the shield member 18 is in contact with the lower surface 26 a of the conductive member 26. The other of the contact surfaces 18 a of the shield member 18 is in contact with the upper surface of the bottom surface portion 22 a of the frame 22. In one embodiment, the distance between the lower surface 26 a of the conductive member 26 and the upper surface of the bottom surface portion 22 a of the frame 22 in the state before the ROSA 14 fitted with the shield member 18 is accommodated in the housing 16 is The distance between the two contact surfaces 18a of the shield member 18 is smaller. Accordingly, when the two contact surfaces 18a come into contact with the lower surface 26a of the conductive member 26 and the upper surface of the bottom surface portion 22a of the frame 22, the support portion 18b is deformed, and the support portion 18b conducts the two contact surfaces 18a. The bottom surface 26 a of the manufacturing member 26 and the bottom surface portion 22 a of the frame 22 are biased. As a result, the shield member 18 is securely connected to the frame ground of the housing 16.

  The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, in the optical transceiver 10, the case 14a of the ROSA 14 is made of resin, but only the case 12a of the TOSA 12 or both the case 14a of the ROSA 14 and the case 12a of the TOSA 12 may be made of resin. . Further, the shield member 18 may be attached only to the TOSA 12 or to both the TOSA 12 and the ROSA 14.

  DESCRIPTION OF SYMBOLS 10 ... Optical transceiver, 12 ... Optical transmission subassembly (TOSA), 12a ... Case, 12b ... Sleeve, 12c ... Stem, 12d ... Flexible printed circuit board, 14 ... Optical reception subassembly (ROSA), 14a ... Case, 14b ... Sleeve , 14c ... stem, 14d ... flexible printed circuit board, 14e ... outer peripheral surface, 14f ... flat surface part, 14g ... projection, 16 ... housing, 18 ... shield member, 18a ... contact surface, 18b ... support part, 18c ... flat surface part, 18d ... hole, 20 ... circuit board, 22 ... frame, 22a ... bottom surface part, 22b ... side wall part, 24 ... optical receptacle, 26 ... conductive member, 26a ... lower surface, 28 ... case.

Claims (4)

An optical receiver subassembly for converting an optical signal into an electrical signal and outputting the electrical signal;
An optical transmission subassembly for converting an electrical signal into an optical signal and outputting the optical signal;
A housing provided to cover the optical receiving subassembly and the optical transmitting subassembly;
With
The optical receiving subassembly and the optical transmitting subassembly have a case defining an outer peripheral surface about an axis extending in a first direction;
The case of at least one of the optical receiving subassembly and the optical transmitting subassembly is made of resin.
A metal shield member provided to cover the outer peripheral surface of the at least one optical subassembly;
The housing includes two metal surfaces facing each other in a second direction orthogonal to the first direction,
The shield member includes two contact surfaces that contact the two surfaces of the housing, and a portion that biases the two contact surfaces against the two surfaces of the housing.
Optical transceiver.   The optical transceiver according to claim 1, wherein the case of the optical receiving subassembly is made of resin. The outer peripheral surface of the case of the at least one optical subassembly includes one protrusion, and includes two flat portions facing each other in a direction orthogonal to the first direction,
The shield member has a hole into which the protrusion fits,
The shield member has two flat portions in contact with the two flat portions of the outer peripheral surface of the case.
The optical transceiver according to claim 1 or 2.   In a state before the shield member is attached to the outer peripheral surface of the case, a distance between the two flat portions of the outer peripheral surface of the case is larger than a distance between the two flat portions of the shield member. The optical transceiver according to claim 3.

Images