Patents by Inventor Thomas Frach

Thomas Frach has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10989819
    Abstract: 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.
    Type: Grant
    Filed: October 24, 2017
    Date of Patent: April 27, 2021
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Herfried Karl Wieczorek, Torsten Solf, Thomas Frach
  • Publication number: 20200284922
    Abstract: 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.
    Type: Application
    Filed: October 24, 2017
    Publication date: September 10, 2020
    Inventors: Herfried Karl WIECZOREK, Torsten SOLF, Thomas FRACH
  • Patent number: 10656288
    Abstract: 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.
    Type: Grant
    Filed: January 2, 2018
    Date of Patent: May 19, 2020
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Thomas Frach, Klaus Fiedler
  • Publication number: 20190137636
    Abstract: 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.
    Type: Application
    Filed: January 4, 2019
    Publication date: May 9, 2019
    Inventor: Thomas FRACH
  • Patent number: 9995829
    Abstract: When detecting scintillation events in a nuclear imaging system, time-stamping and energy-gating processing is incorporated into autonomous detection modules (ADM) (14) to reduce downstream processing. Each ADM (14) is removably coupled to a detector fixture (13), and comprises a scintillation crystal array (66) and associated light detect or (s) (64), such as a silicon photomultiplier or the like. The light detector(s) (64) is coupled to a processing module (62) in or on the ADM (14), which performs the energy gating and time-stamping.
    Type: Grant
    Filed: November 16, 2009
    Date of Patent: June 12, 2018
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Carsten Degenhardt, Thomas Frach, Gordian Prescher
  • Publication number: 20180156926
    Abstract: 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.
    Type: Application
    Filed: January 2, 2018
    Publication date: June 7, 2018
    Inventors: Thomas FRACH, Klaus FIEDLER
  • Patent number: 9874644
    Abstract: 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.
    Type: Grant
    Filed: January 19, 2016
    Date of Patent: January 23, 2018
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Thomas Frach, Klaus Fiedler
  • Publication number: 20160320496
    Abstract: 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.
    Type: Application
    Filed: July 14, 2016
    Publication date: November 3, 2016
    Inventors: Thomas FRACH, Andreas THON
  • Patent number: 9423511
    Abstract: When designing detector arrays for diagnostic imaging devices, such as PET or SPECT devices, a virtual detector, or pixel, combines scintillator crystals (10, 20, 40) with photodetectors (12) 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 (10, 20, 40) 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 (54) can be associated with each of a plurality of photodetectors (52). A gamma ray hit on a specific crystal is then determined by a table lookup of adjacent photodetectors (52) that register equal light intensities, and the crystal (54) common to such photodetectors (52) is identified as the location of the hit.
    Type: Grant
    Filed: April 29, 2008
    Date of Patent: August 23, 2016
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Thomas Frach, Andreas Thon
  • Patent number: 9405024
    Abstract: 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.
    Type: Grant
    Filed: July 24, 2014
    Date of Patent: August 2, 2016
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Thomas Frach, Gordian Prescher
  • Patent number: 9354332
    Abstract: A detector (22) detects an event. First and second time-to-digital converters (TDCs) (70, 72) generate first and second time stamps (TS1, TS2) for the detection of the event. The first TDC and the second TDC are both synchronized with a common clock signal (62) that defines a fixed time offset between the second TDC and the first TDC. An autocalibration circuit (120) 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 (28) propogates a trigger signal from a trigger detector of the array of detectors to the first and second TDC's. Skew correction circuitry (132, 134, 136, 142, 60, 162) adjusts a timestamp (TS) based on which detector is the triggering detector.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: May 31, 2016
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Bernardus Antonius Maria Zwaans, Thomas Frach
  • Publication number: 20160146949
    Abstract: 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.
    Type: Application
    Filed: January 19, 2016
    Publication date: May 26, 2016
    Inventors: Thomas FRACH, Klaus FIEDLER
  • Patent number: 9335421
    Abstract: 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.
    Type: Grant
    Filed: July 25, 2011
    Date of Patent: May 10, 2016
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Thomas Frach, Klaus Fiedler
  • Patent number: 9268033
    Abstract: 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.
    Type: Grant
    Filed: April 8, 2010
    Date of Patent: February 23, 2016
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Thomas Frach, Klaus Fiedler
  • Patent number: 9176241
    Abstract: A photon detector (10) includes a detector array (12) comprising single photon avalanche diode (SPAD) detectors (14) configured to break down responsive to impingement of a photon. Trigger circuitry (34) is configured to generate a trigger signal responsive to break down of a SPAD detector of the detector array. Latches (20, 22) are configured to store position coordinates of SPAD detectors of the detector array that are in break down. The latches are configured to latch responsive to a trigger signal generated by the trigger circuitry. The latches may include row latches (22) each connecting with a logical “OR” combination of SPAD detectors of a corresponding row of the detector array, and column latches (20) each connecting with a logical “OR” combination of SPAD detectors of a corresponding column of the detector array. Time to digital converter (TDC) circuitry (28) may generate a digital time stamp for the trigger signal.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: November 3, 2015
    Assignee: Koninklijke Philips N.V.
    Inventor: Thomas Frach
  • Patent number: 9087755
    Abstract: A photodiode includes an anode (1202, 1302, 1402) and a cathode (1306, 1406) formed on a semiconductor substrate (402). A vertical electrode (702, 1314, 1414) is in operative electrical communication with a buried component (502, 1312, 1412) of the photodiode. In one implementation, the photodiode is an avalanche photodiode of a silicon photomultiplier. The substrate may also include integrated CMOS readout circuitry (1102).
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: July 21, 2015
    Assignee: Koninklijke Philips N.V.
    Inventor: Thomas Frach
  • Publication number: 20150076357
    Abstract: 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.
    Type: Application
    Filed: November 20, 2014
    Publication date: March 19, 2015
    Inventor: Thomas FRACH
  • Patent number: 8975907
    Abstract: A photodetector array includes a plurality of photodetector cells such as avalanche photodiodes and readout circuits. An array self-tester tests a dark count or other performance characteristic of the cells. The test is performed in connection with the manufacture of the array or following the installation of the array in a detection system.
    Type: Grant
    Filed: January 31, 2012
    Date of Patent: March 10, 2015
    Assignee: Koninklijke Philips N.V.
    Inventors: Gordian Prescher, Thomas Frach
  • Patent number: 8921754
    Abstract: A PET scanner (10) includes a ring of detector modules (16) encircling an imaging region (18). Each of the detector modules includes one or more sensor avalanche photodiodes (APDs) (34) that are biased in a breakdown region in a Geiger mode. The sensor APDs (34) output pulses in response to light from a scintillator corresponding to incident photons. A reference APD (36) 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 (44). Based on the measurement, a bias control feedback loop (42) directs a variable voltage generator (48) to adjust a bias voltage applied to the APDs (34, 36) such that a difference (86) between a voltage of a breakdown pulse (68) and a preselected logic voltage level (70) is minimized.
    Type: Grant
    Filed: February 5, 2010
    Date of Patent: December 30, 2014
    Assignee: Koninklijke Philips N.V.
    Inventor: Thomas Frach
  • Publication number: 20140336987
    Abstract: 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.
    Type: Application
    Filed: July 24, 2014
    Publication date: November 13, 2014
    Applicant: KONINKLIJKE PHILIPS N.V.
    Inventors: Thomas FRACH, Gordian PRESCHER