Designing the Response of an Optical Quad-Cell as Position-Sensitive Detector

This paper focuses on 2-D position-sensitive detectors based on the quad-cell architecture, and presents design solutions to compensate the usual nonlinear response of a conventional quad-cell to radially symmetric light spots. It has been observed that by changing the quad-cell perimeter geometry and by adding a properly sized central region with a different sensitivity, the output response can be linearized. The simulation results presented herein will enable one to estimate the most appropriate quad-cell design for the requirements of a given application.