Atlanta Fiber System Experiment: GaAIAs Laser Transmitter for Lightwave Transmission Systems

Abstract

A feedback-stabilized GaAlAs injection laser optical-communication source for transmission of NRZ data at 44.736 Mb/s has been built and tested. The emitter-coupled driver circuit and the feedback scheme utilizing an operational amplifier are described. Two special hybrid packages contain the circuit components on thick-film substrates, and the package holding the laser provides laser heat-sinking as well as the interface between the laser and optical fiber. The laser source packages that were fabricated were capable of launching an average power of >0.5 mW into the 55-μm diameter core of a graded-index fiber (N.A. = 0.23). The sources draw a total of 0.9 W from the +5.0 V and −5.2 V (±5 percent) supplies and operate properly over a temperature range of 5° to 55°C.