Method for calibrating a device for detecting ionising radiation, the device comprising a detector capable of generating electrical charges under the effect of an interaction between ionising radiation in said detector, the method including the following steps: a) irradiation of the detector using a known reference source (Sref) so as to generate interactions in the detector, b) selection of a plurality of correction factors (j), and determination of reference spectra (Sp refj ), each reference spectrum being associated with a correction factor (j), each reference spectrum representing a distribution of the amplitude (A) of the signal (S) detected when the detector is irradiated by said reference source (Sref), the amplitude (A) of the detected signal being modulated by said correction factor (j); c) detection of a plurality of interactions in the detector during said irradiation and, for each interaction, measurement of the amplitude A of an electronic signal S generated by said detector; d) for each detected interaction, determination of a calibration function F such that: ▪ each calibration function F is defined on a plurality of correction factors j, ▪ each term F(j) of said calibration function represents a probability associated with said correction factor j ▪ each term F(j) being updated at each detected interaction, by combining the amplitude A measured during this interaction with each reference spectrum Sp ref j, e) determination of a correction factor j corr by identifying a remarkable point of said calibration function F. a) irradiation of the detector using a known reference source (Sref) so as to generate interactions in the detector, b) selection of a plurality of correction factors (j), and determination of reference spectra (Sp refj ), each reference spectrum being associated with a correction factor (j), each reference spectrum representing a distribution of the amplitude (A) of the signal (S) detected when the detector is irradiated by said reference source (Sref), the amplitude (A) of the detected signal being modulated by said correction factor (j); c) detection of a plurality of interactions in the detector during said irradiation and, for each interaction, measurement of the amplitude A of an electronic signal S generated by said detector; d) for each detected interaction, determination of a calibration function F such that: ▪ each calibration function F is defined on a plurality of correction factors j, ▪ each term F(j) of said calibration function represents a probability associated with said correction factor j ▪ each term F(j) being updated at each detected interaction, by combining the amplitude A measured during this interaction with each reference spectrum Sp ref j, ▪ each calibration function F is defined on a plurality of correction factors j, ▪ each term F(j) of said calibration function represents a probability associated with said correction factor j ▪ each term F(j) being updated at each detected interaction, by combining the amplitude A measured during this interaction with each reference spectrum Sp ref j, e) determination of a correction factor j corr by identifying a remarkable point of said calibration function F. <EOS>