Integrated photodetector for VCSEL feedback control

摘要

An integrated photodetector means for controlling the output of a light source, where the control means is a photodetector formed on a silicon-on-insulator substrate. The integrated photodetector senses the optical power from the light source and provides an electrical feedback signal which can be used to adjust the DC bias levels of the light source control driver circuit. The approach readily lends itself to large arrays of light sources bonded to silicon-on-sapphire driver circuits and is especially suitable for controlling light sources such as VCSELs in arrays such as are found in communications systems.