Abstract

The principle of transmitting information using free-space optics poses a serious challenge to collecting diagnostic signals within large-scale digital photonic systems¹. High concentrations of parallel optical channels and localized electronic signals bring about great difficulties in monitoring high speed operations using conventional contact techniques. Up to now, the typical diagnostic procedure was to sample a portion of the light reflected from the output modulators with a system viewport and form a remote magnified image. A high-sensitivity photodetector was then sequentially aligned with each spot to transform the signal to an electronic format that could be monitored using an electronic oscilloscope. This sampling procedure and other electro-optic sampling techniques^2,3 developed for high speed systems are too time consuming when many signals must be actively monitored.

© 1995 Optical Society of America