Optical communication device, optical transceiver using the same and manufacturing method of optical communication device

An optical communication device, comprising:

• a first means for including at least an optical module which inputs or outputs an optical signal, and a peripheral circuit connecting electrically with the optical module;
• a second means for including an electric connector which inputs and/or outputs an electric signal;
• and
• a third means for adjusting a relative position of the first means and the second means, and transmitting the electric signal among these boards;
• wherein the optical module is surface mounted on the first means, and
• the first means is formed of one substrate including
• a peripheral circuit mount part, having a thickness, which mounts the peripheral circuit,
• a module mount part which mounts the optical module while being formed in a substrate thickness thinner than the thickness of the peripheral circuit mount part,
• a first through-hole terminal which path through the peripheral circuit mount part and connects wirings of the third means and a terminal of the peripheral circuit, and
• a second through-hole terminal which path through the module board mount part and connects wirings of the third means and a terminal of the optical module, in order that a current loop length of a return current produced between the optical module and the peripheral circuit may become short corresponding to a difference between the thickness of the peripheral circuit mount part and the substrate thickness of the module mount part.

An optical transceiver, comprising:

• an optical communication device, comprising:
• a module board which includes at least an optical module for inputting and/or outputting an optical signal, and a peripheral circuit connecting electrically with the optical module;
• a connector board which includes an electric connector inputting and/or outputting an electric signal;
• and
• a flexible board which adjusts a relative position of the module board and the connector board, and transmits the electric signal among these boards;
• and
• a case, comprising:
• a mount part which receives the optical communication device;
• a cable connecting part that optically connects a communication cable with the optical module;
• and
• a main body connecting part that electrically connects an electrical connector with a main communication device;
• wherein:
• the optical module transforms the optical signal received via the communication cable into electric signal, and provides an output to the main communication device via the electric connector;
• and
• the optical module transforms the electric signal received from the main communication device via the electric connector into the optical signal, and provides an output to the communication cable;
• the optical module is surface mounted on the module board;
• and
• the module board is formed of one substrate including
• a peripheral circuit mount part, having a thickness, which mounts the peripheral circuit,
• a module mount part which mounts the optical module while being formed in a substrate thickness thinner than the thickness of the peripheral circuit mount part,
• a first through-hole terminal which path through the peripheral circuit mount part and connects wirings of the flexible board and a terminal of the peripheral circuit, and
• a second through-hole terminal which path through the module board mount part and connects wirings of the flexible board and a terminal of the optical module, in order that a current loop length of a return current produced between the optical module and the peripheral circuit may become short corresponding to a difference between the thickness of the peripheral circuit mount part and the substrate thickness of the module mount part.

A manufacturing method of an optical communication device, comprising:

• a device arrangement procedure for arranging at least an optical module on a flex-rigid circuit board which includes a module board, a connector board, a the flexible board;
• and
• a reflow procedure for soldering the optical module to the module board by heating a solder pattern on the module board;
• wherein the optical module is surface mounted on the module board, and
• the module board is formed of one substrate including
• a peripheral circuit mount part, having a thickness, which mounts the peripheral circuit,
• a module mount part which mounts the optical module while being formed in a substrate thickness thinner than the thickness of the peripheral circuit mount part,
• a first through-hole terminal which path through the peripheral circuit mount part and connects wirings of the flexible board and a terminal of the peripheral circuit, and
• a second through-hole terminal which path through the module board mount part and connects wirings of the flexible board and a terminal of the optical module, in order that a current loop length of a return current produced between the optical module and the peripheral circuit may become short corresponding to a difference of between the thickness of the peripheral circuit mount part and the substrate thickness of the module mount part.