High efficiency photon detection

Patent metadata

Field	Value
Publication number	US-2017205361-A1
Application number	US-201615379006-A
Country	US
Kind code	A1
Filing date	Dec 14, 2016
Priority date	Dec 15, 2015
Publication date	Jul 20, 2017
Grant date	—

Abstract

A detection pixel includes a material that is chosen so that its (averaged) atomic number density leads to the Compton process being the dominant scattering mechanism in response to incident photons, leading to production of Compton electrons with sufficient number and kinetic energy to produce an electric or magnetic response in the material. The incident photon and Compton electrons each have a characteristic travel distance in the material, and the detection pixel has at least one dimension that is selected according to a range defined by these characteristic travel distances. The detection pixels may be arranged in an array for imaging.

First claim

What is claimed is:

1 . An apparatus comprising:
a detection pixel including a first material that is responsive to incident photons to produce Compton electrons and an electric or magnetic response in the first material, wherein the incident photons and the Compton electrons each have a characteristic travel distance in the first material; and wherein the detection pixel has at least one dimension that is selected according to at least one of the characteristic travel distance of the incident photons and the characteristic travel distance of the Compton electrons.

2 . The apparatus of claim 1 wherein the first material includes a ferroelectric material, a piezoelectric material, or a multiferroic material.

3 . The apparatus of claim 1 wherein the first material includes at least one of titanates of lead, bismuth, barium, zirconium, and their alloys.

4 . The apparatus of claim 1 wherein the first material includes at least one of a niobate and a tantalate.

5 . (canceled)

6 . The apparatus of claim 1 wherein the first material is responsive to photons in a first energy range to produce Compton electrons, wherein the first energy range is substantially between 20 KeV and 5 MeV.

7 . The apparatus of claim 1 wherein the first material is selected to have an electric or magnetic response to incident photons in the x-ray frequency band.

8 . The apparatus of claim 1 wherein the detection pixel is characterized by a cross-sectional dimension and a length, and wherein the cross-sectional dimension of the detection pixel is selected according to the characteristic travel distance of the Compton electrons.

9 . The apparatus of claim 8 wherein the cross-sectional dimension of the detection pixel is at least one of a diameter, a side of a square, and a side of a rectangle.

10 - 11 . (canceled)

12 . The apparatus of claim 1 wherein the detection pixel is characterized by a cross-sectional dimension and a length, and wherein the cross-sectional dimension of the detection pixel is selected according to the characteristic travel distance of the incident photons.

13 . The apparatus of claim 1 wherein the detection pixel is characterized by a cross-sectional dimension and a length, and wherein the length of the detection pixel is selected according to the characteristic travel distance of the incident photons.

14 - 15 . (canceled)

16 . The apparatus of claim 1 further comprising detection circuitry configured to measure the electric or magnetic response associated with the detection pixel.

17 . The apparatus of claim 16 wherein the detection pixel and the detection circuitry form a resonant circuit having a resonance.

18 . The apparatus of claim 17 further comprising circuitry configured to determine at least one property of the resonance.

19 . (canceled)

20 . The apparatus of claim 18 further comprising circuitry configured to determine at least one change in the at least one property of the resonance, wherein the determined at least one change corresponds to a passage of photons in the detection pixel.

21 . The apparatus of claim 17 wherein the detection pixel is configured as an inductor or a capacitor in the resonant circuit, and wherein the detection circuitry is configured to measure a relative resonant frequency of the resonant circuit.

22 . The apparatus of claim 21 wherein the detection circuitry is further configured to measure a change in the relative resonant frequency of the resonant circuit, wherein the change in the relative resonant frequency of the resonant circuit corresponds to a detection of photons by the detection pixel.

23 . The apparatus of claim 1 wherein the detection pixel forms at least a portion of a capacitor having a capacitance, and wherein the capacitance is indicative of an interaction of photons with the detection pixel.

24 . The apparatus of claim 1 wherein the detection pixel forms at least a portion of an inductor having an inductance, and wherein the inductance is indicative of an interaction of photons with the detection pixel.

25 . A system comprising:
an array of detection pixels, each detection pixel in the array of detection pixels including a first material that is responsive to incident photons to produce Compton electrons and an electric or magnetic response in the first material, wherein the incident photons and the Compton electrons each have a characteristic travel distance in the first material; and wherein each detection pixel in the array of detection pixels has at least one dimension that is selected according to at least one of the characteristic travel distance of the incident photons and the characteristic travel distance of the Compton electrons.

26 . The system of claim 25 wherein each detection pixel in the array of detection pixels is separated from a subset of nearest neighbor detection pixels by a gap comprising a dielectric material.

27 - 30 . (canceled)

31 . The system of claim 25 wherein each detection pixel in the array of detection pixels includes a first material, and wherein the first materials of the detection pixels in the array are not all the same.

32 . The system of claim 25 wherein the first material includes a ferroelectric material or a multiferroic material.

33 . The system of claim 25 wherein the first material includes at least one of titanates of lead, bismuth, barium, zirconium, and their alloys.

34 . The system of claim 25 wherein the first material includes at least one of a niobate and a tantalate.

35 . (canceled)

36 . The system of claim 25 wherein the first material is selected to have an electric or magnetic response to incident photons in the x-ray energy band.

37 . The system of claim 25 wherein each detection pixel in the array is characterized by a cross-sectional dimension and a length, and wherein the cross-sectional dimensions of the detection pixels are selected according to at least one of the characteristic travel distance of the incident photons and the characteristic travel distance of the Compton electrons.

38 . The system of claim 37 wherein the cross-sectional dimension of the detection pixel is at least one of a diameter, a side of a square, and a side of a rectangle.

39 - 40 . (canceled)

41 . The system of claim 37 wherein the incident photons have a characteristic travel distance in the first material for a selected range of energies, and wherein the lengths of the detection pixels are selected according to the characteristic travel distance.

42 . The system of claim 37 wherein the incident photons have a characteristic travel distance in the first material for a selected range of electromagnetic energies, and wherein the array has at least one dimension that is selected according to the characteristic travel distance.

43 . The system of claim 25 further comprising a source configured to produce the incident photons, wherein the array of detection pixels is arranged relative to the source to receive the photons produced by the source.

44 - 45 . (canceled)

46 . The system of claim 25 further comprising detection circuitry configured to measure the electric or m

Assignees

• Elwha Llc

Inventors

• Cannara Rachel
• Sharifi Fred
• Smolyanitsky Alex

Classifications

• G01N23/20066 Primary

  Measuring inelastic scatter of gamma rays, e.g. Compton effect · CPC title

• G01N2223/063

  inelastic scatter, e.g. Compton effect · CPC title

• G01V5/005

  Physics · mapped topic

• G01N23/046

  using tomography, e.g. computed tomography [CT] · CPC title

• G01N2223/501

  array · CPC title