Laser Packaging for Very High Speed Lightwave Systems

Laser modules with broadband characteristics are required in multi-gigabit/s lightwave systems and in some analog applications. In addition, optical isolation is necessary to prevent spectral instabilities and enhanced intensity noise arising from optical reflections. We report here on fully packaged 1.3micron distributed feedback lasers having a bandwidth in excess of 9 GHz, and modulation capability to 8 Gb/s. When operated directly into an InGaAs APD, receiver sensitivities as low as -25.2 dBm have been obtained at a bit error rate of 10 sup -9. We also report on techniques for providing optical isolation both internal and external to the laser module.