A photon-counting camera is used to generate images of thermal (blackbody) objects. Analytical estimates of the count rates that can be obtained for thermal objects in the 300–800-K temperature range are given for several different photocathode materials. Images generated with a photon-counting camera are compared with those obtained with infrared cameras that operate in the 3–5 and 8–12-μm ranges. It is found that high-resolution images of thermal objects can be generated with the photon-counting camera. The noise-equivalent differential temperature that can be obtained with a photon-counting camera is given as a function of the number of detected photoevents. Pattern-recognition experiments that use low-light-level (quantum-limited) images of thermal objects are reported. In the experiments, photon-limited images of thermal objects are correlated with a reference function that is stored in computer memory. The number of detected photoevents required to reliably distinguish between two thermal objects is determined and compared to the noise-equivalent differential temperature figure of merit.
© 1992 Optical Society of America
Original Manuscript: August 2, 1991
Published: August 10, 1992
Edward A. Watson and G. Michael Morris, "Imaging thermal objects with photon-counting detectors," Appl. Opt. 31, 4751-4757 (1992)