US 12,468,050 B2
Direct energy windowing for photon counting detectors
Katsuyuki Taguchi, Elkridge, MD (US)
Assigned to THE JOHNS HOPKINS UNIVERSITY, Baltimore, MD (US)
Filed by THE JOHNS HOPKINS UNIVERSITY, Baltimore, MD (US)
Filed on Dec. 13, 2022, as Appl. No. 18/065,101.
Application 18/065,101 is a continuation in part of application No. 17/795,697, granted, now 12,196,897, previously published as PCT/US2021/015288, filed on Jan. 27, 2021.
Claims priority of provisional application 62/966,463, filed on Jan. 27, 2020.
Prior Publication US 2023/0138853 A1, May 4, 2023
Int. Cl. G01T 1/17 (2006.01); A61B 6/42 (2024.01); G01T 1/24 (2006.01)
CPC G01T 1/17 (2013.01) [A61B 6/4241 (2013.01); G01T 1/247 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of counting respective photons having energy levels within at least a first energy window and a second energy window, wherein the first energy window is higher than the second energy window, the method implemented using:
a first counter corresponding to a count of photons of the first energy window, the first counter coupled to a source indicative of a photon detection of at least a lower end of the first energy window,
a second counter corresponding to a count of photons of the second energy window, and
an AND gate comprising an output coupled to the second counter,
wherein a first input of the AND gate is coupled via a NOT gate to the source indicative of a photon detection of at least a lower end of the first energy window,
wherein a second input of the AND gate is coupled to a source indicative of a photon detection of at least a lower end of the second energy window,
the method comprising:
receiving, at the source indicative of a photon detection of at least a lower end of the second energy window, an indication of a photon detection of at least the lower end of the second energy window;
starting a timer for a predetermined time interval upon the receiving, at the source indicative of a photon detection of at least a lower end of the second energy window, the indication of the photon detection of at least the lower end of the second energy window;
prior to the timer reaching an end of the predetermined time interval, receiving, at the source indicative of a photon detection of at least a lower end of the first energy window, an indication of a photon detection of at least the lower end of the first energy window, wherein the first counter is incremented; and
when the timer reaches an end of the predetermined time interval, evaluating the output of the AND gate, wherein the second counter is not incremented.