Assembly of VCSEL light source and VCSEL optical detector

摘要

There is provided an assembly of a light source and an optical detector, each using a vertical cavity surface emitting laser (VCSEL). To control light emission of the VCSEL light source, spontaneous light emitted laterally therefrom is converted into an electrical signal. The optical detector for monitoring is provided around the light source to supply the feedback electrical signal. The inner surface facing the light source of the optical detector is circular to absorb the spontaneous light and the outer surface thereof is polygonal having a plurality of peaks and valleys. Therefore, most of spontaneous light absorbed in the optical detector is reflected within, not penetrating the outer surface thereof, thereby extending the path of the spontaneous light in the optical detector and increasing the light intensity converted into an electrical signal. <IMAGE>