The output of uncooled microbolometer is nonuniform, and the traditional two-point nonuniformity correction method requires a tight restriction on substrate temperature. The circuit proposed by this article can relax the restriction on the substrate temperature and perform nonuniformity correction when reading out the image signal. The dummy pixels reduce static current. And the Column shared DACs transfer correction data to the gates of MOS transistors and the positive reference edge of amplifier, to control the bias current of detector and dummy one, and set the start point of integration. This circuit has higher sensitivity, wider dynamic range, and frame frequency of more than 30 Hz for 128×128 array. PSPICE simulation results seem that this circuit functions well.
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