Abstract: The present invention relates to a photon detector, a detector device and an imaging apparatus for detection of radiation, in particular gamma radiation. The photon detector comprises a direct conversion detector (11) configured to detect gamma radiation and generate direct conversion signals responsive to impingement of photons, a single photon avalanche diode. SPAD, detector array (12) comprising a plurality of SPAD detectors (13) configured to detect Cherenkov radiation generated in the direct conversion detector in response to impingement of photons and generate SPAD detection signals, and an electrode array (14) comprising aurality of electrodes arranged on top of the direct conversion detector and between the direct conversion detector and the SPAD detector array and configured to read out the direct conversion signals. The SPAD detector array substantially covers a surface on one side of the direct conversion detector.

Abstract: A positron emission tomography imaging system (100) includes a plurality of detector elements (1301..i) and a plurality of compute elements (1401..j). Each compute element (1401..j) comprises one or more of the detector elements (1301..i), and the compute elements (1401..j) are arranged around the bore (110) of the PET imaging system. Each compute element (1401..j) includes a first communication path (1601..j) coupling the compute element to an adjacent compute element in a5circumferential direction around the bore, and a second communication path (1701..j) coupling the compute element to a non-adjacent compute element in the circumferential direction. Each compute element (1401..j) includes a processor configured to receive the event data generated by its one or more detector elements (1301..i), and to communicate the event data to the processor of its adjacent compute element, and to the processor of its non-adjacent compute element, via its first communication path10(1601..

Abstract: The present invention relates to a photon counting detector and method. The detector (20) comprises a scintillator (21) configured to convert incident gamma radiation into optical photons, a pixelated photodetector (22) configured to detect the flux of optical photons, and circuitry (23). The circuitry (23) is configured to iteratively determine, per photodetector pixel, a photon count by accumulating the number of optical photons detected by the respective photodetector pixel during an integration time, assign the photon count, per photodetector pixel, to one of multiple energy bins by use of energy thresholds separating the multiple energy bins, and dynamically adapt, per photodetector pixel or group of photodetector pixels, the energy thresholds for use in a subsequent iteration based on information on the estimated photon count of said photodetector pixel or group of photodetector pixels in the subsequent iteration.

Abstract: The present invention relates to a photon counting detector and method. The detector comprises a scintillator (21) configured to convert incident gamma radiation into optical photons; a pixelated photodetector (20, 30) configured to detect the flux of optical photons wherein the pixelated photodetector is a silicon photomultiplier, SiPM, detector, wherein each photodetector pixel comprises an array of silicon avalanche photo diodes, SPADs; and circuitry (23, 90) configured to carry out, per photodetector pixel, the steps of controlling a stop timing at which one or more functions of the photodetector pixel are stopped; determining a first photon count by accumulating the number of optical photons detected by the SPADs of the respective photodetector pixel from the start of an integration period up to the stop timing; and estimating a second photon count based on the first photon count and the stop timing, the second photon count representing an estimate of the photon count for the total integration period.

Abstract: The present invention relates to a photon counting detector and method. The detector (2) comprises a scintillator (10) configured to convert incident gamma radiation into optical photons, a pixelated photodetector (11) configured to detect the flux of optical photons, and circuitry (12). The circuitry is configured to determine, per photodetector pixel, a photon count by accumulating the number of optical photons detected by the respective photodetector pixel during an integration time period, compare, per photodetector pixel or group of photodetector pixels, a single photon count or multiple photon counts to a counting threshold, detect an event if, per photodetector pixel or group of photodetector pixels, the one or more photon counts exceed the counting threshold, and temporarily adapt the counting threshold for use in the comparison in one or more subsequent integration time periods based on the energy of the detected event.

Abstract: The present invention relates to a photon counting detector comprising a scintillator (10, 20) configured to convert incident gamma radiation into optical photons; a pixelated photodetector (11, 22) configured to detect the flux of optical photons wherein the pixelated photodetector (22) is a silicon photomultiplier, SiPM, detector, wherein each photodetector pixel comprises an array of silicon avalanche photo diodes, SPADs; and circuitry (80, 90) configured to heat SPADs by applying, if dark count rate of a SPAD exceeded a dark count rate threshold, an elevated reverse bias voltage to the SPAD to force the SPAD into breakdown with current flowing through the SPAD for the time of a heating period to locally increase the temperature of the SPAD, and controlling the length of the heating period.

Abstract: The present application relates generally to silicon photomultiplier (SiPM) detector arrays. In one aspect, there is a system including an array of cells each including a single-photon avalanche diode (SPAD) reverse-biased above a breakdown voltage of the SPAD. Each cell may further include trigger logic connected to the SPAD, and configured to output a trigger signal indicating whether the SPAD is in breakdown. Each cell may still further include a conditional recharge circuit configured to recharge the SPAD conditional upon both (i) the recharge circuit applying the recharge signal to the cell and (ii) the trigger signal output by the trigger logic of the cell indicating the SPAD of the cell is in breakdown.

Abstract: The present application relates generally to silicon photomultiplier (SiPM) detector arrays. In one aspect, there is a system including an array of cells each including a single-photon avalanche diode (SPAD) reverse-biased above a breakdown voltage of the SPAD. The system may further include a trigger network configured to generate pulses on a trigger line in response to SPADs of the array undergoing breakdown. The system may still further include a pulse-width filter configured to block pulses on the trigger line whose pulse width is less than a threshold width.

Abstract: The present invention relates to a photon detector, a detector device and an imaging apparatus for detection of radiation, in particular gamma radiation. The photon detector comprises a direct conversion detector (11) configured to detect gamma radiation and generate direct conversion signals responsive to impingement of photons, a single photon avalanche diode. SPAD, detector array (12) comprising a plurality of SPAD detectors (13) configured to detect Cherenkov radiation generated in the direct conversion detector in response to impingement of photons and generate SPAD detection signals, and an electrode array (14) comprising aurality of electrodes arranged on top of the direct conversion detector and between the direct conversion detector and the SPAD detector array and configured to read out the direct conversion signals. The SPAD detector array substantially covers a surface on one side of the direct conversion detector.

Abstract: A positron emission tomography imaging system (100) includes a plurality of gamma detector elements (130i), a plurality of detector cassettes (140j), and mounting frame (150). Each detector cassette (140j) is configured to replaceably receive a plurality of gamma detector elements (130i). The mounting frame (150) is configured to replaceably receive the detector cassettes (140j) at a plurality of angular positions (fk) around the axis (120) of the bore (110) such that at each angular position (fk) a plurality of detector cassettes (140j) are receivable along a direction parallel to the axis (120) of the bore (110), and a plurality of gamma detector elements (130j) are receivable within a cassette (140j) in a transaxial direction with respect to the axis (120) of the bore (110).

Abstract: The present application relates generally to silicon photomultiplier (SiPM) detector arrays. In one aspect, there is a system including an array of cells each including a single-photon avalanche diode (SPAD) reverse-biased above a breakdown voltage of the SPAD. Each cell may further include trigger logic connected to the SPAD, and configured to output a trigger signal indicating whether the SPAD is in breakdown. Each cell may still further include a conditional recharge circuit configured to recharge the SPAD conditional upon both (i) the recharge circuit applying the recharge signal to the cell and (ii) the trigger signal output by the trigger logic of the cell indicating the SPAD of the cell is in breakdown.

Abstract: A positron emission tomography imaging system (100) includes a plurality of detector elements (1301..i) and a plurality of compute elements (1401..j). Each compute element (1401..j) comprises one or more of the detector elements (1301..i), and the compute elements (1401..j) are arranged around the bore (110) of the PET imaging system. Each compute element (1401..j) includes a first communication path (1601..j) coupling the compute element to an adjacent compute element in a5circumferential direction around the bore, and a second communication path (1701..e) coupling the compute element to a non-adjacent compute element in the circumferential direction. Each computeelement (1401..j) includes a processor configured to receive the event data generated by its one or more detector elements (1301..i), and to communicate the event data to the processor of its adjacent computeelement, and to the processor of its non-adjacent compute element, via its first communication path10(1601..

Abstract: The present application relates generally to silicon photomultiplier (SiPM) detector arrays. In one aspect, there is a system including an array of cells each including a single-photon avalanche diode (SPAD) reverse-biased above a breakdown voltage of the SPAD. The system may further include a trigger network configured to generate pulses on a trigger line in response to SPADs of the array undergoing breakdown. The system may still further include a pulse-width filter configured to block pulses on the trigger line whose pulse width is less than a threshold width.

Abstract: A detector array (200) (200) according to the present teachings includes: a substrate (101) (101) adapted to function as a core layer of an optical waveguide (210) (210); a plurality of single photon avalanche photodiodes (SPAD (100)s (201)) disposed along a width of the substrate (101); a first cladding layer (202) (202) disposed over the plurality of SPADs (201) and along the width; and a second cladding layer (206) (206) disposed above the substrate and along the width.

Abstract: The present application relates generally to silicon photomultiplier (SiPM) detector arrays. In one aspect, there is a system including an array of cells each including a single-photon avalanche diode (SPAD) reverse-biased above a breakdown voltage of the SPAD. Each cell may further include trigger logic connected to the SPAD, and configured to output a trigger signal indicating whether the SPAD is in breakdown. Each cell may still further include a conditional recharge circuit configured to recharge the SPAD conditional upon both (i) the recharge circuit applying the recharge signal to the cell and (ii) the trigger signal output by the trigger logic of the cell indicating the SPAD of the cell is in breakdown.

Abstract: The present application relates generally to silicon photomultiplier (SiPM) detector arrays. In one aspect, there is a system including an array of cells each including a single-photon avalanche diode (SPAD) reverse-biased above a breakdown voltage of the SPAD. The system may further include a trigger network configured to generate pulses on a trigger line in response to SPADs of the array undergoing breakdown. The system may still further include a pulse-width filter configured to block pulses on the trigger line whose pulse width is less than a threshold width.

Abstract: The present invention relates to a calibration method for a gamma ray detector (100) including a pixelated scintillator array (110) for emitting scintillation photons at photo conversion positions (94) in response to incident gamma rays (90), and a pixelated photodetector array (120) for determining a spatial intensity distribution of the scintillation photons. The present invention bases on the idea that using the concept of optical light sharing of scintillation photons, which are emitted in one element, i.e., one scintillator pixel (112) of the scintillator array (110) and distributed over multiple photodetector pixels (122) of the pixelated photodetector army (120), allows obtaining an estimate for the time skew between adjacent photodetector pixels (122). The present invention further relates to a calibration module (200) for a gamma ray detector (100) including a recorder (210) and a processing module (220) for performing the function of the above-explained method.

Abstract: The present invention relates to a calibration method for a gamma ray detector (100) including a pixelated scintillator array (110) for emitting scintillation photons at photo conversion positions (94) in response to incident gamma rays (90), and a pixelated photodetector array (120) for determining a spatial intensity distribution of the scintillation photons. The present invention bases on the idea that using the concept of optical light sharing of scintillation photons, which are emitted in one element, i.e., one scintillator pixel (112) of the scintillator array (110) and distributed over multiple photodetector pixels (122) of the pixelated photodetector array (120), allows obtaining an estimate for the time skew between adjacent photodetector pixels (122). The present invention further relates to a calibration module (200) for a gamma ray detector (100) including a recorder (210) and a processing module (220) for performing the function of the above-explained method.

Abstract: The present application relates generally to silicon photomultiplier (SiPM) detector arrays. In one aspect, there is a system including an array of cells each including a single-photon avalanche diode (SPAD) reverse-biased above a breakdown voltage of the SPAD. Each cell may further include trigger logic connected to the SPAD, and configured to output a trigger signal indicating whether the SPAD is in breakdown. Each cell may still further include a conditional recharge circuit configured to recharge the SPAD conditional upon both (i) the recharge circuit applying the recharge signal to the cell and (ii) the trigger signal output by the trigger logic of the cell indicating the SPAD of the cell is in breakdown.

Abstract: The present application relates generally to silicon photomultiplier (SiPM) detector arrays. In one aspect, there is a system including an array of cells each including a single-photon avalanche diode (SPAD) reverse-biased above a breakdown voltage of the SPAD. The system may further include a trigger network configured to generate pulses on a trigger line in response to SPADs of the array undergoing breakdown. The system may still further include a pulse-width filter configured to block pulses on the trigger line whose pulse width is less than a threshold width.