Method to identify defective detectors of thermal focal plane array based on its frequency domain characteristics

The targets on the earth can be detected by its radiation in thermal band from the remote sensing satellite day and night. The State-of-the-art infrared detector technology makes it possible to use thermal focal plane array (FPA) to probe interested target in the boundless sea. Unfortunately due to accidental and uncontrollable factors during detector production, there always are defective detectors in the thermal focal plane array, more or less. We can call it dark element if it has no or weaker response, or can call it hot element if it has abnormal stronger response. These two kinds of defective response cannot be mitigated by linearity correcting, contrarily it will be harmful to the target detecting. Method to identify these defective detectors by analyzing their frequency domain characteristics is stated here. The recognition rate of defective detectors is greater than 98% by using such method.