DETECTION AND CORRECTION OF A LOSS OF CALIBRATION OF MICROBOLOMETER THERMAL IMAGING RADIOMETERS

摘要

A method for detecting a loss of calibration of a thermal imaging radiometer including an array of imaging microbolometers and a gauge microbolometer is provided. The detection method includes applying a first and a second electrical stimulation to the gauge microbolometer to bring it to a first and a second predetermined temperature, followed by measuring an ohmic responsivity of the gauge microbolometer that is representative of a difference between the first and second electrical stimulations. The measured ohmic responsivity is compared with a reference ohmic responsivity, such that a loss of calibration is signaled whenever the measured and reference ohmic responsivities differ by more than a predetermined threshold. A correction method is also provided, including steps of the detection method, to yield a corrected voltage response function for each imaging microbolometer. Advantageously, the methods involve probing the electrical response of the gauge microbolometer without requiring thermoregulated blackbody calibrations sources.