Applied Optoelectronics, Inc.
Laser subassembly having impedance-matching network integrated on laser submount and a transmitter optical subassembly (TOSA) implementing same

Abstract:

The present disclosure is generally directed to a laser subassembly for use in a TOSA module that includes an integrated impedance matching network to enable a plurality of selectable resistance configurations to ensure the driving circuit and laser emitter of the TOSA module have matching, or substantially matching, impedances. The laser subassembly includes a substrate with a driving circuit disposed thereon. The driving circuit includes signal conductors for electrically coupling to an external transmit connecting circuit, a conductive laser mounting section, and an impedance matching network. The impedance matching network includes a plurality of resistors, with one or more of the resistors being selectively electrically coupled to the conductive laser mounting section to introduce a selected amount of impedance to minimize or otherwise reduce reflection.