LUMINESCENT DECAY TIME MEASUREMENTS BY USE OF A CCD CAMERA

A video camera of a type using an array of charge coupled devices (CCDs) is utilized to measure a condition, such as temperature, by imaging onto the camera a luminescent signal which contains information of the signal's decay time. The luminescent decay time is measured by comparing, such as by ratioing, the integrated signal values obtained in successive frames of operation of the CCD. One application includes use to measure a two-dimensional temperature distribution across a surface. The surface of interest is either coated with a layer of the luminescent material or emissions from the surface are imaged onto a separate luminescent screen. Another application is as a multiplexer and detector system for a large array of optical fiber sensors, a luminescent signal from each of the sensors being imaged through its respective fiber onto a unique one or more of CCD photosites.