Abstract: A method of calibrating time in a Positron Emission Tomography (PET) device includes obtaining original time information and energy information of a first pulse signal collected by a detecting module during a scanning process of the PET device. A detector of the PET device includes a plurality of detecting modules. The original time information of the first pulse signal includes a moment at which an amplitude of the first pulse signal begins to be greater than a threshold. The method includes determining a pulse time calibration amount corresponding to the energy information of the first pulse signal according to stored information indicative of a correspondence between the pulse time calibration amount and the energy information of each detecting module. The method includes generating calibrated time information of the first pulse signal by calibrating the original time information with the pulse time calibration amount; and reconstructing a PET image based on the generated calibrated time information.

Abstract: A method of calibrating time in a Positron Emission Tomography (PET) device includes obtaining original time information and energy information of a first pulse signal collected by a detecting module during a scanning process of the PET device. A detector of the PET device includes a plurality of detecting modules. The original time information of the first pulse signal includes a moment at which an amplitude of the first pulse signal begins to be greater than a threshold. The method includes determining a pulse time calibration amount corresponding to the energy information of the first pulse signal according to stored information indicative of a correspondence between the pulse time calibration amount and the energy information of each detecting module. The method includes generating calibrated time information of the first pulse signal by calibrating the original time information with the pulse time calibration amount; and reconstructing a PET image based on the generated calibrated time information.

Abstract: A method of calibrating time in a Positron Emission Computed Tomography (PET) device includes determining a rising edge slope of an electrical signal corresponding to a photon which is detected by a detector of the PET device when the PET device is used to scan a part of a subject to be examined. The method includes determining a time shift corresponding to the rising edge slope based on a correspondence between the rising edge slope and the time shift; calibrating time information of the photon based on the time shift; and reconstructing a PET image of the part of the subject to be examined based on the calibrated time information of the photon.

Abstract: A method of calibrating time in a Positron Emission Computed Tomography (PET) device includes determining a rising edge slope of an electrical signal corresponding to a photon which is detected by a detector of the PET device when the PET device is used to scan a part of a subject to be examined. The method includes determining a time shift corresponding to the rising edge slope based on a correspondence between the rising edge slope and the time shift; calibrating time information of the photon based on the time shift; and reconstructing a PET image of the part of the subject to be examined based on the calibrated time information of the photon.

Abstract: Methods and devices for calibrating a gain of a scintillator detector are disclosed, where a scintillation crystal of the scintillator detector includes two or more energy regions. In an example, the scintillation crystal of the scintillator detector is adopted as a radiation source for calibrating. Electric signals outputted from a rear end of the scintillator detector are collected, and actual counts of the electric signals from each of at least two energy regions of the scintillation crystal at a specified position are obtained, respectively. Then, a gain of the scintillator detector may be adjusted according to the obtained actual counts of the electric signals from the at least two energy regions.

Abstract: Methods, systems, and machine-readable storage mediums for determining response lines for reconstructing images are provided. An example imaging method includes: receiving single event signals in a detector module and associated with a single event, determining a crystal in the detector module and corresponding to a maximum single event signal of the single event signals, determining an actual energy weighting factor of the crystal, determining an actual depth position corresponding to the actual energy weighting factor of the crystal according to associations between depth positions of the crystal and respective reference energy weighting factors for the crystal, as an acting position in the detector module for the single event, determining a response line of a coincidence event according to respective acting positions in the detector module for two single events constituting the coincidence event, the two single events including the single event, and reconstructing an image according to the response line.

Abstract: A method of adjusting a gain of a detector is provided in the present disclosure. According to an example, whether a gain of a photomultiplier tube in the detector meets a gain determination condition may be determined, where the gain determination condition may indicate that an absolute of a difference between the gain of the photomultiplier tube and a target gain is within a predetermined numerical range. When the gain of the photomultiplier tube does not meet the gain determination condition, a voltage of the photomultiplier tube may be adjusted, such that the gain of the photomultiplier tube meets the gain determination condition.

Abstract: Methods, systems, and machine-readable storage mediums for determining response lines for reconstructing images are provided. An example imaging method includes: receiving single event signals in a detector module and associated with a single event, determining a crystal in the detector module and corresponding to a maximum single event signal of the single event signals, determining an actual energy weighting factor of the crystal, determining an actual depth position corresponding to the actual energy weighting factor of the crystal according to associations between depth positions of the crystal and respective reference energy weighting factors for the crystal, as an acting position in the detector module for the single event, determining a response line of a coincidence event according to respective acting positions in the detector module for two single events constituting the coincidence event, the two single events including the single event, and reconstructing an image according to the response line.

Abstract: An apparatus for recognizing a position of a crystal in a nuclear detector, including: a silicon semiconductor detector array arranged in a crystal array in the nuclear detector, where each row/or column of silicon semiconductor detectors is configured to output a sum of voltages outputted by the silicon semiconductor detectors in the row/or column at a row/or column signal output end; row signal comparing modules, one to one correspondingly connected to each row signal output end and configured to obtain a row comparison result for each row of silicon semiconductor detectors; column signal comparing modules, one to one correspondingly connected to each column signal output end and configured to obtain a column comparison result for each column of silicon semiconductor detectors; and a crystal position recognizing module configured to recognize a position of a crystal hit by a photon according to each row comparison result and each column comparison result.

Abstract: A method of adjusting a gain of a detector is provided in the present disclosure. According to an example, whether a gain of a photomultiplier tube in the detector meets a gain determination condition may be determined, where the gain determination condition may indicate that an absolute of a difference between the gain of the photomultiplier tube and a target gain is within a predetermined numerical range. When the gain of the photomultiplier tube does not meet the gain determination condition, a voltage of the photomultiplier tube may be adjusted, such that the gain of the photomultiplier tube meets the gain determination condition.

Abstract: Methods and devices for calibrating a gain of a scintillator detector are disclosed, where a scintillation crystal of the scintillator detector includes two or more energy regions. In an example, the scintillation crystal of the scintillator detector is adopted as a radiation source for calibrating. Electric signals outputted from a rear end of the scintillator detector are collected, and actual counts of the electric signals from each of at least two energy regions of the scintillation crystal at a specified position are obtained, respectively. Then, a gain of the scintillator detector may be adjusted according to the obtained actual counts of the electric signals from the at least two energy regions.

Abstract: An apparatus for recognizing a position of a crystal in a nuclear detector, including: a silicon semiconductor detector array arranged in a crystal array in the nuclear detector, where each row/or column of silicon semiconductor detectors is configured to output a sum of voltages outputted by the silicon semiconductor detectors in the row/or column at a row/or column signal output end; row signal comparing modules, one to one correspondingly connected to each row signal output end and configured to obtain a row comparison result for each row of silicon semiconductor detectors; column signal comparing modules, one to one correspondingly connected to each column signal output end and configured to obtain a column comparison result for each column of silicon semiconductor detectors; and a crystal position recognizing module configured to recognize a position of a crystal hit by a photon according to each row comparison result and each column comparison result.