Radiation camera with high spatial, temporal, and energy resolution

• US 6,180,946 B1
• Filed: 04/16/1998
• Issued: 01/30/2001
• Est. Priority Date: 04/17/1997
• Status: Expired due to Term

• Current Assignee: Lexitek Inc.
• Original Assignee: Lexitek Inc.
• Inventors: Ebstein, Steven M.
• Primary Examiner(s): Ham, Seungsook
• Assistant Examiner(s): HANIG, RICHARD E
• Application Number:
  US09/061,455
• Time in Patent Office: 1,020 Days
• Field of Search: 250/370.11, 250/363.06, 250/390.01, 250/390.11, 250/369, 250/367, 250/370.1, 250/390.12
• US Class Current: 250/370.11
• CPC Class Codes: G01T 1/20 with scintillation detectors
• CPC Class Codes: G01T 1/295 using coded aperture devices, e.g. Fresnel zone plates handling of radiation of particles, e.g. using diaphragms, collimators, diffraction G21K1/00

Abstract

An imaging ionizing radiation detector with a high pixel resolution is described. The detector comprises a scintillating crystal and associated sensors which determine the energy and position of the scintillation with high spatial, temporal, and energy resolution. The position sensing is done with a photon counting and position sensitive detector. The detector can achieve sub-millimeter resolution and the position determination is performed at MHZ rates.

Claims

1. An ionizing radiation detector for determining position of radiation and at least one characteristic of radiation besides position, the ionizing radiation detector comprising:

a scintillator, wherein in response to the radiation the scintillator emits a first at least one photon in a first path and a second at least one photon in a second path;

a photon counting and position sensitive detector in the first path in optical communication with the scintillator responsive to the first at least one photon for providing position information of the radiation, the photon counting and position sensitive detector capable of counting a single photon and determining the position of radiation corresponding to a single photon; and

a photodetector in the second path responsive to the second at least one photon for determining at least one characteristic of the radiation other than position of the radiation.

2. The ionizing radiation detector of claim 1 wherein the at least one characteristic of the radiation is the energy level of the radiation.

3. The ionizing radiation detector of claim 1 wherein the at least one characteristic of the radiation is the type of radiation.

14. The ionizing radiation detector of claim 1 wherein

the photon counting and position sensitive detector is a precision analog photon address detector.

4. An ionizing radiation detector for determining the position and at least one other characteristic of radiation, the ionizing radiation detector comprising:

a scintillator for emitting photons in response to radiation;

at least one photo multiplier receiving the emitted photons from the scintillator;

a photon counting and position sensitive detector in optical communication with the scintillator for detecting the position of the radiation; and

an optical lens for coupling the emitted photons received from the scintillator to the photon counting and position sensitive detector.

5. The ionizing radiation detector of claim 4, wherein the scintillator has an internally facing mirrored front radiation entrance and at least one side, the internally facing mirrored front radiation entrance directs some of the emitted photons out the side of the scintillator.

6. The ionizing radiation detector of claim 4, wherein

the scintillator is rectangular in shape and has an internally facing mirrored radiation entrance, two mirrored side windows, two clear side windows and a clear exit window through which emitted photons may exit the scintillator.

7. The ionizing radiation detector of claim 6, wherein

the at least one photo multiplier is positioned adjacent to at least one of the two clear side windows.

8. An ionizing radiation detector comprising:

an imaging plate which has at least one aperture through which radiation may pass;

a scintillator in optical alignment with the imaging plate, the scintillator receiving radiation and producing emitted photons;

a photon counting and position sensitive detector in optical communication with the scintillator for detecting the position of the radiation, the photon counting and position sensitive detector capable of counting a single photon and determining the position of radiation corresponding to a single photon; and

at least one photo multiplier in optical alignment with the scintillator, the at least one photo multiplier receiving some of the emitted photons for determining at least one characteristic of the radiation besides position.

9. The ionizing radiation detector of claim 8 wherein the at least one characteristic of the radiation is the energy level of the radiation.

10. The ionizing radiation detector of claim 8 wherein the at least one characteristic of the radiation is the type of radiation.

13. The ionizing radiation detector of claim 8 wherein

the scintillator further comprises a fast-phosphor output screen.

11. An ionizing radiation detector for determining position of radiation and the energy level of radiation, the ionizing radiation detector comprising:

a scintillator for emitting photons in response to gamma radiation;

at least one photodetector responsive to the radiation for determining the energy level of the gamma radiation; and

a photon counting and position sensitive detector in optical communication with the scintillator for providing the position of the gamma radiation, the photon counting and position sensitive detector capable of counting a single photon and determining the position of radiation corresponding to a single photon.

12. An ionizing radiation detector for determining position of radiation and the type of radiation, the ionizing radiation detector comprising:

a scintillator for emitting photons in response to neutron radiation;

at least one photodetector responsive to the neutron radiation for distinguishing the type of radiation; and

a photon counting and position sensitive detector in optical communication with the scintillator for providing the position of the neutron radiation, the photon counting and position sensitive detector capable of counting a single photon and determining the position of radiation corresponding to a single photon.

15. An ionizing radiation detector for determining the position and at least one characteristic of radiation besides position, the ionizing radiation detector comprising:

a scintillator for emitting photons in response to radiation;

at least one photo multiplier for receiving the emitted photons from the scintillator;

a precision analog photon address detector in optical communication with the scintillator for detecting the position of the radiation, the precision analog photon address detector capable of counting each photon and determining the position of radiation corresponding to each photon; and

an optical lens for coupling the emitted photons received from the scintillator to the photon counting and position sensitive detector.

16. The ionizing radiation detector of claim 15, wherein

the scintillator has an internally facing mirrored radiation entrance and at least one side, the mirrored radiation entrance directs some of the emitted photons out the side of the scintillator.

17. The ionizing radiation detector of claim 15, wherein

the scintillator is rectangular in shape and has an internally facing mirrored radiation entrance, two mirrored side windows, two clear side windows and a clear exit window through which emitted photons may exit the scintillator.

18. The ionizing radiation detector of claim 17, wherein

the at least one photo multiplier is positioned adjacent to at least one of the two clear side windows.

19. An ionizing radiation detector comprising:

an imaging plate which has at least one aperture through which radiation may pass;

a scintillator in optical alignment with the imaging plate for receiving radiation and producing emitted photons;

a precision analog photon address detector in optical communication with the scintillator for detecting the position of the radiation, the precision analog photon address detector capable of counting each photon and determining the position of radiation corresponding to each photon; and

at least one photo multiplier in optical alignment with the scintillator receiving some of the emitted photons for determining at least one characteristic of the radiation besides position.

20. The ionizing radiation detector of claim 19 wherein the at least one characteristic of the radiation is the energy level of the radiation.

21. The ionizing radiation detector of claim 19 wherein the at least one characteristic of the radiation is the type of radiation.

24. The ionizing radiation detector of claim 19 wherein

the scintillator further comprises a fast-phosphor output screen.

22. An ionizing radiation detector for determining position of radiation and energy level of radiation, the ionizing radiation detector comprising:

a scintillator for emitting photons in response to gamma radiation;

at least one photodetector responsive to the gamma radiation for determining the gamma radiation'"'"'s energy level; and

a precision analog photon address detector in optical communication with the scintillator for providing the position of the gamma radiation, the precision analog photon address detector capable of counting each photon and determining the position of radiation corresponding to each photon.

23. An ionizing radiation detector for determining position of radiation and type of radiation, the ionizing radiation detector comprising:

a scintillator for emitting photons in response to neutron radiation;

at least one photodetector responsive to the radiation for determining the type of radiation; and

a precision analog photon address detector in optical communication with the scintillator for providing the position of the radiation, the precision analog photon address detector capable of counting each photon and determining the position of radiation corresponding to each photon.