FIELD: information technology.
SUBSTANCE: signal charges of neighbouring frames are accumulated in a photodetector successively for a time interval exceeding the duration of the broadcast television subframe (Tk), and during accumulation of signal charges of a first frame from neighbouring frames, nondestructive measurement of the level of the formed charge relief is performed with period Tk, in the interval of its last row, by performing non-scanning "charge-voltage" conversion. Video signal voltage is detected and its value is compared with threshold voltage based on the criterion of a predetermined signal-to-noise ratio, wherein the accumulation process of the first frame continues if the current comparison result is less than the threshold, or is stopped if the current comparison result is equal to or higher than the threshold.
EFFECT: increase in sensitivity through automatic selection of accumulation time of compared frames depending on background illumination of the controlled scene.
2 cl, 14 dwg
