A method for sampling a pulse signal, comprising: step S1, collecting a plurality of first sampling points on a rising edge portion of the pulse signal according to a plurality of preset sampling thresholds, where each of the first sampling points is represented by one of the preset sampling thresholds and first time corresponding to the one of the preset sampling thresholds; step S2, collecting a plurality of second sampling points on a falling edge portion of the pulse signal according to the plurality of preset sampling thresholds, where each of the second sampling points is represented by one of the preset sampling thresholds and second time corresponding to the one of the preset sampling thresholds; and step S3, collecting a third sampling point of the pulse signal at third time separated from the first or second time by a preset time interval (Δ), where the third sampling point is represented by the third time and a response amplitude corresponding to the third time, characterized in that the preset time interval (Δ) is determined in the following manners of: calculating, for each of a plurality of pre-collected pulse signals, a difference between an abscissa value of a pulse amplitude point and an abscissa value of a selected calibration point, where the calibration point is one of the plurality of the first sampling points or one of the plurality of the second sampling points; performing Gaussian fitting on the calculated differences to obtain Gaussian curves and fitted parameters; and comparing discrete degrees of the obtained Gaussian curves with each other, and using the fitted parameter of the Gaussian curve conforming to an optimal normal distribution as the preset time interval (Δ). step S1, collecting a plurality of first sampling points on a rising edge portion of the pulse signal according to a plurality of preset sampling thresholds, where each of the first sampling points is represented by one of the preset sampling thresholds and first time corresponding to the one of the preset sampling thresholds; step S2, collecting a plurality of second sampling points on a falling edge portion of the pulse signal according to the plurality of preset sampling thresholds, where each of the second sampling points is represented by one of the preset sampling thresholds and second time corresponding to the one of the preset sampling thresholds; and step S3, collecting a third sampling point of the pulse signal at third time separated from the first or second time by a preset time interval (Δ), where the third sampling point is represented by the third time and a response amplitude corresponding to the third time, characterized in that the preset time interval (Δ) is determined in the following manners of: calculating, for each of a plurality of pre-collected pulse signals, a difference between an abscissa value of a pulse amplitude point and an abscissa value of a selected calibration point, where the calibration point is one of the plurality of the first sampling points or one of the plurality of the second sampling points; performing Gaussian fitting on the calculated differences to obtain Gaussian curves and fitted parameters; and comparing discrete degrees of the obtained Gaussian curves with each other, and using the fitted parameter of the Gaussian curve conforming to an optimal normal distribution as the preset time interval (Δ). calculating, for each of a plurality of pre-collected pulse signals, a difference between an abscissa value of a pulse amplitude point and an abscissa value of a selected calibration point, where the calibration point is one of the plurality of the first sampling points or one of the plurality of the second sampling points; performing Gaussian fitting on the calculated differences to obtain Gaussian curves and fitted parameters; and comparing discrete degrees of the obtained Gaussian curves with each other, and using the fitted parameter of the Gaussian curve conforming to an optimal normal distribution as the preset time interval (Δ).