Optical transceiver module providing EMI shielding and electrical isolation between a signal ground and a chassis ground
View Patent ↗A transceiver module includes a receptacle assembly that isolates the signal ground potential at which an opto-electronic subsystem operates from the chassis ground potential at which the transceiver module housing is maintained, while also helping maintain optical alignment of the system elements. The receptacle assembly can include a receptacle made of metal, a coupling made of metal, and a connector made of a dielectric material. The connector is interposed between the receptacle and the coupling to electrically isolate the signal ground potential of the opto-electronic subsystem from the chassis ground potential of the housing and receptacle. As the metal receptacle is mounted in an opening of the housing, it helps shield the housing against EMI.
1. A transceiver module, comprising:
a housing made of an electrically conductive material;
an opto-electronic subsystem mounted in the housing, the opto-electronic subsystem having an optical axis;
a receptacle made of an electrically conductive material, the receptacle mounted in an opening in the housing and mateable with an optical cable plug aligned with the optical axis;
a coupling made of an electrically conductive material, the coupling in mechanical and electrical contact with the opto-electronic subsystem; and
a connector made of a dielectric material, the connector disposed between the receptacle and the coupling and aiding mechanical alignment of the receptacle and the coupling with the optical axis, whereby the connector electrically isolates a chassis ground potential of the housing and receptacle from a signal ground potential of the opto-electronic subsystem.
2. The transceiver module claimed in claim 1 , wherein the connector is substantially ring-shaped.
3. The transceiver module claimed in claim 1 , wherein:
the receptacle has a cylindrical receptacle body portion with a cylindrical receptacle cavity;
the coupling has a cylindrical coupling body portion with a cylindrical coupling cavity; and
the connector has a first cylindrical portion mating with the receptacle cavity, a second cylindrical portion mating with the coupling cavity, and a flange portion between the first and second cylindrical portions.
4. The transceiver module claimed in claim 3 , wherein:
the receptacle is made of metal;
the coupling is made of metal; and
the connector is made of a plastic material.
5. A transceiver module, comprising:
a housing made of an electrically conductive material, the housing elongated in a direction of a housing axis;
an elongated opto-electronic transmitter system in the housing extending in the direction of the housing axis; and
an elongated opto-electronic receiver system in the housing extending in the direction of the housing axis;
wherein at least one of the transmitter system and receiver system comprises:
an opto-electronic subsystem having an optical axis oriented in the direction of the housing axis;
a receptacle made of an electrically conductive material, the receptacle mounted in an opening in the housing and mateable with an optical cable plug aligned with the optical axis;
a coupling made of an electrically conductive material, the coupling in mechanical and electrical contact with the opto-electronic subsystem; and
a connector made of a dielectric material, the connector disposed between the receptacle and aiding mechanical alignment of the receptacle and the coupling with the optical axis, whereby the connector electrically isolates a chassis ground potential of the housing and receptacle from a signal ground potential of the opto-electronic subsystem.
6. A method of operation of a transceiver module, the transceiver module comprising a housing made of an electrically conductive material, an opto-electronic subsystem, a receptacle made of an electrically conductive material and mounted in an opening in the housing, a coupling made of an electrically conductive material and in mechanical and electrical contact with the opto-electronic subsystem, and a connector made of a dielectric material and disposed between the receptacle and the coupling, the method of operation comprising:
mating an optical cable with the receptacle; and
operating the opto-electronic subsystem to communicate an optical signal between the opto-electronic subsystem and the optical cable, the opto-electronic subsystem having a node coupled to a signal ground potential, and the housing and the receptacle coupled to a chassis ground potential;
wherein the connector electrically isolates the signal ground potential from the chassis ground potential while aiding mechanical alignment of the receptacle and the coupling with the opto-electronic subsystem.