Hitachi, Ltd.

Hitachi Communication System, Inc.

Yuuki Sato

Nobuhiro Matsudaira

Atsushi Murata

An optical transmitter can communicate at a transmission speed exceeding Gb/s with a low bit error rate. An optical transmission module includes a semiconductor module having a semiconductor laser and an impedance matching element, a driver circuit for driving the semiconductor laser to emit an optical signal, and an optical fiber for transmitting the optical signal. The impedance matching element matches an impedance of the semiconductor laser module to an impedance of the driver circuit. The optical transmission module includes an impedance element for reducing an input impedance of the semiconductor laser module as viewed from the driving circuit in order to reduce a fall time of the optical signal. Impedance matching elements and are added to remove possible mismatching between the module and the driver circuit caused by a manufacturing error and to improve the yield of the module.

Growing community of inventors

Yokohama, Japan

Yuuki Sato