A pixel acquisition circuit, comprising: a photodetection unit operative to output a first electrical signal corresponding to the light signal illuminating thereon in real time; a filter-amplifier unit with its input terminal coupled with the output terminal of the photodetection unit, and operative to perform amplification on the first electrical signal and filter out the signal component below a frequency threshold on the first electrical signal, so as to output a second electrical signal; a threshold comparison unit with its input terminal coupled with the output terminal of the filter-amplifier unit, and operative to determine whether the second electrical signal is greater than a first threshold, and/or whether the second electrical signal is less than a second threshold which is lower than the first threshold, and generate an activation instruction signal when the second electrical signal is greater than the first threshold or less than the second threshold; characterized in that the pixel acquisition circuit further comprising: a sample and hold unit with its input terminal coupled with the output terminal of the photodetection unit and its output terminal coupled with the an interface bus of the image sensor; an activation control unit operative to, in response to receiving an activation instruction signal, instruct the sample and hold unit to acquire and buffer the first electrical signal corresponding to the instant in time when the activation instruction signal being received, and send a transmission request for the buffered first electrical signal to the interface bus. a photodetection unit operative to output a first electrical signal corresponding to the light signal illuminating thereon in real time; a filter-amplifier unit with its input terminal coupled with the output terminal of the photodetection unit, and operative to perform amplification on the first electrical signal and filter out the signal component below a frequency threshold on the first electrical signal, so as to output a second electrical signal; a threshold comparison unit with its input terminal coupled with the output terminal of the filter-amplifier unit, and operative to determine whether the second electrical signal is greater than a first threshold, and/or whether the second electrical signal is less than a second threshold which is lower than the first threshold, and generate an activation instruction signal when the second electrical signal is greater than the first threshold or less than the second threshold; characterized in that the pixel acquisition circuit further comprising: a sample and hold unit with its input terminal coupled with the output terminal of the photodetection unit and its output terminal coupled with the an interface bus of the image sensor; an activation control unit operative to, in response to receiving an activation instruction signal, instruct the sample and hold unit to acquire and buffer the first electrical signal corresponding to the instant in time when the activation instruction signal being received, and send a transmission request for the buffered first electrical signal to the interface bus. a sample and hold unit with its input terminal coupled with the output terminal of the photodetection unit and its output terminal coupled with the an interface bus of the image sensor; an activation control unit operative to, in response to receiving an activation instruction signal, instruct the sample and hold unit to acquire and buffer the first electrical signal corresponding to the instant in time when the activation instruction signal being received, and send a transmission request for the buffered first electrical signal to the interface bus.