to calculate a covariance matrix of the atomic time label and determine a parameter of a time label combination and the time label combination parameter calculation module 400 is configured to test and operate the acquired parameter of the time label combination as shown in fig3 to fig1 the present disclosure is further understood in conjunction with fig3 to fig1 fig3 is a scintillation pulse sample according to the present disclosure a rising time period of the pulse is approximately 0 7 ns a time constant a time period during which the pulse is attenuated to 1 e of a falling edge of the pulse is approximately 22 ns and the pulse is an electrical pulse outputted from r9800 and is collected by a high speed oscillograph dpo71604 fig4 is a scintillation pulse data after alignment operation in a database according to the present disclosure the pulses are drawn in a timeline after the time of arrival of the pulses is aligned a main noise type of the scintillation pulse can be deduced from an envelope line of the data fig5 is a schematic diagram of a multi leading edge discrimination time label according to an embodiment of the present disclosure the multi leading edge discrimination time label is an example of multi threshold time discrimination for which only the rising edge which changes fast is considered and an influence of the falling edge on the time performance is ignored for an encoding part the label method is shown in fig5 which includes a comparator array a logic signal acquisition unit and an interpolation or correction module fig6 is a schematic diagram of a multi.