Tiny Incident Light Angle Sensor

A novel device for detecting the intensity and the angles of incoming light is presented. The silicon chip with 1 mm edge length comprises a segmented photo diode with four active areas within the inclined surfaces of a deep etched cavity. Simple signal difference analysis of these signals allow for accurate azimuth and inclination measurement in the range of 0 to 360deg and 0 to 55deg, respectively. Using an artificial neural network (ANN) calibration strategy the operation range of inclination can be increased up to 85deg with typical angle errors below 2deg. In this report we present details on design, fabrication, signal analysis and calibration strategies.