System to detect failed pixels in a sensor array

摘要

A system to test operation of an optical sensor is disclosed. The optical sensor includes one or more photosensitive devices configured to convert light to electrical signals. A test light source is included within the housing of the optical sensor. The test light source is periodically pulsed on to emit radiation at a sufficient intensity to saturate each of the photosensitive devices. Each of the photosensitive devices generates a signal corresponding to the intensity of light detected at that device. A logic circuit uses the signals corresponding to the intensity of light to identify whether each of the photosensitive devices is performing at an acceptable level.

主权项

1. An optical sensor for use in a safety system, comprising
a housing; an optical receiver mounted within the housing; an optical source mounted within the housing and configured to emit radiation at an intensity sufficient to saturate the optical receiver wherein the emitted radiation remains within the housing between the optical source and the optical receiver; and a logic circuit configured to:
receive at least one signal from the optical receiver corresponding to the intensity of the radiation received by the optical receiver,compare the intensity of the radiation received by the optical receiver to a predetermined threshold, andgenerate a signal responsive to the intensity of the radiation received by the optical receiver.