Koninklijke Philips Corporation N.V.

Avago Technologies International Sales Pte. Limited

Koninklijke Philips Electronics N.v.

Philips Intellectual Property & Standards Gmbh

Thomas Frach

Gordian Prescher

Torsten Solf

Andreas Thon

Klaus Fiedler

Carsten Degenhardt

Herfried Karl Wieczorek

Dennis Groben

Christoph Herrmann

Gereon Vogtmeier

Roger Steadman Booker

Anco Heringa

Guenter Zeitler

Christian Baeumer

Prabhat Agarwal

Andreas Goedicke

Bernardus Antonius Maria Zwaans

Jacobus A J M Deckers

Anja Schmitz

Rob Ballizany

Herfried Wieczorek

Sjaak Deckers

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.

Recharge circuit for digital silicon photomultipliers

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.

Time-domain filtering of gamma events

The present invention relates to a calibration method for a gamma ray detector () including a pixelated scintillator array () for emitting scintillation photons at photo conversion positions () in response to incident gamma rays (), and a pixelated photodetector array () 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 () of the scintillator array () and distributed over multiple photodetector pixels () of the pixelated photodetector army (), allows obtaining an estimate for the time skew between adjacent photodetector pixels (). The present invention further relates to a calibration module () for a gamma ray detector () including a recorder () and a processing module () for performing the function of the above-explained method. Still further, the present invention relates to a gamma my detector () as well as to a medical imaging device () comprising this gamma my detector ().

Sub-pixel time skew correction for positron emission tomography (PET)

When designing detector arrays for diagnostic imaging devices, such as PET or SPECT devices, a virtual detector, or pixel, combines scintillator crystals with photodetectors in ratios that deviate from the conventional 1:1 ratio. For instance, multiple photodetectors can be glued to a single crystal to create a virtual pixel which can be software-based or hardware-based. Light energy and time stamp information for a gamma ray hit on the crystal can be calculated using a virtualizer processor or using a trigger line network and time-to-digital converter logic. Additionally or alternatively, multiple crystals can be associated with each of a plurality of photodetectors. A gamma ray hit on a specific crystal is then determined by a table lookup of adjacent photodetectors that register equal light intensities, and the crystal common to such photodetectors is identified as the location of the hit.

Virtual pet detector and quasi-pixelated readout scheme for pet

A PET scanner includes a ring of detector modules encircling an imaging region. Each of the detector modules includes one or more sensor avalanche photodiodes (APDs) that are biased in a breakdown region in a Geiger mode. The sensor APDs output pulses in response to light from a scintillator corresponding to incident photons. A reference APD also biased in a breakdown region in a Geiger mode is optically shielded from light and outputs a voltage that is measured by an analog to digital converter. Based on the measurement, a bias control feedback loop directs a variable voltage generator to adjust a bias voltage applied to the APDs such that a difference between a voltage of a breakdown pulse and a preselected logic voltage level is minimized.

Advanced temperature compensation and control circuit for single photon counters

The invention relates to a gamma radiation detector that provides compensation for the parallax effect. The gamma radiation detector includes a plurality of scintillator elements, a planar optical detector array, and a pinhole collimator that includes a pinhole aperture. Each scintillator element has a gamma radiation receiving face and an opposing scintillation light output face. The gamma radiation receiving face of each scintillator element faces the pinhole aperture for generating scintillation light in response to gamma radiation received from the pinhole aperture. The scintillator elements are arranged in groups. Each group has a group axis that is aligned with the pinhole aperture and is perpendicular to the radiation receiving face of each scintillator in that group. The scintillation light output faces of each of the scintillator elements are in optical communication with the planar optical detector array.

Gamma radiation detector with parallax compensation

A radiation detector includes an array of detector pixels each including an array of detector cells. Each detector cell includes a photodiode biased in a breakdown region and digital circuitry coupled with the photodiode and configured to output a first digital value in a quiescent state and a second digital value responsive to photon detection by the photodiode. Digital triggering circuitry is configured to output a trigger signal indicative of a start of an integration time period responsive to a selected number of one or more of the detector cells transitioning from the first digital value to the second digital value. Readout digital circuitry accumulates a count of a number of transitions of detector cells of the array of detector cells from the first digital state to the second digital state over the integration time period.

Digital silicon photomultiplier for TOF-PET

When detecting scintillation events in a nuclear imaging system, time-stamping and energy-gating processing is incorporated into autonomous detection modules (ADM) () to reduce downstream processing. Each ADM () is removably coupled to a detector fixture (), and comprises a scintillation crystal array () and associated light detect or (s) (), such as a silicon photomultiplier or the like. The light detector(s) () is coupled to a processing module () in or on the ADM (), which performs the energy gating and time-stamping.

Autonomous detector module as a building block for scalable PET and SPECT systems

When designing detector arrays for diagnostic imaging devices, such as PET or SPECT devices, a virtual detector, or pixel, combines scintillator crystals () with photodetectors () in ratios that deviate from the conventional 1:1 ratio. For instance, multiple photodetectors can be glued to a single crystal to create a virtual pixel () which can be software-based or hardware-based. Light energy and time stamp information for a gamma ray hit on the crystal can be calculated using a virtualizer processor or using a trigger line network and time-to-digital converter logic. Additionally or alternatively, multiple crystals () can be associated with each of a plurality of photodetectors (). A gamma ray hit on a specific crystal is then determined by a table lookup of adjacent photodetectors () that register equal light intensities, and the crystal () common to such photodetectors () is identified as the location of the hit.

Virtual PET detector and quasi-pixelated readout scheme for PET

A radiation detector module for use in a time-of-flight positron emission tomography (TOF-PET) scanner generates a trigger signal indicative of a detected radiation event. A timing circuit including a first time-to-digital converter (TDC) and a second TDC is configured to output a corrected timestamp for the detected radiation event based on a first timestamp determined by the first TDC and a second timestamp determined by the second TDC. The first TDC is synchronized to a first reference clock signal and the second TDC is synchronized to a second reference clock signal, the first and second reference clock signals being asynchronous.

Method to improve the time resolution of digital silicon photomultipliers

A detector () detects an event. First and second time-to-digital converters (TDCs) () generate first and second time stamps (TS, TS) for the detection of the event. The first TDC and the second TDC are both synchronized with a common clock signal () that defines a fixed time offset between the second TDC and the first TDC. An autocalibration circuit () adjusts the first TDC and the second TDC to keep the time difference between the second time stamp and the first time stamp equal to the fixed time offset between the second TDC and the first TDC. The detector may be a detector array, and trigger circuitry () propogates a trigger signal from a trigger detector of the array of detectors to the first and second TDC's. Skew correction circuitry () adjusts a timestamp (TS) based on which detector is the triggering detector.

Growing community of inventors

Aachen, Germany

Thomas Frach