No-shutter uncooled infrared imaging system and nonuniformity correction method

The invention provides a no-shutter uncooled infrared imaging system and a nonuniformity correction method. The system comprises an optical lens, an infrared detector, a field-programmable gate array, an analog-digital converter, a storage device and an image encoder. The optical lens collects optical signals of a target; the infrared detector converts the optical signals into analog voltage signals which are then converted by the analog-digital converter into digital signals which are output to the field-programmable gate array; the analog-digital converter carries out sampling on the analog signals output by the infrared detector and then transmits the signals to the field-programmable gate array; and the field-programmable gate array processes the digital signals and outputs the processed signals. The method is characterized by, to begin with, collecting response values of the system for the same uniform target background; calculating substrate temperature of an infrared focal plane array; then, calculating background value under the current state according to the background values and the substrate temperature; and finally, carrying out nonuniformity correction by utilizing one-point correction. The method has the advantages of easy realization and high precision and can be widely applied to the current uncooled infrared imaging system.