Photon counting imaging detector system

• US 20080099689A1
• Filed: 10/31/2006
• Published: 05/01/2008
• Est. Priority Date: 10/31/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: DxRay, Inc. (OSI Systems Incorporated)
• Inventors: Barber, William C., Iwanczyk, Jan S., Nygard, Einar
• Granted Patent: US 7,829,860 B2
• Time in Patent Office: Days
• US Class Current: 250/370.09
• CPC Class Codes: G01T 1/17 Circuit arrangements not adapted to a particular type of detector pulse-selection circuits H03K, G01R
• CPC Class Codes: G01T 1/20182 Modular detectors, e.g. tiled scintillators or tiled photodiodes stacked detectors G01T1/20181
• CPC Class Codes: G01T 1/20186 Position of the photodiode with respect to the incoming radiation, e.g. in the front of, below or sideways the scintillator
• CPC Class Codes: G01T 1/247 Detector read-out circuitry for processing gain or off-set correction H04N
• CPC Class Codes: G01T 1/249 specially adapted for use in SPECT or PET SPECT imaging G01T1/1642; PET imaging G01T1/2985; detecting prohibited goods, e.g. weapons, explosives, hazardous substances, contraband or smuggled objects G01V5/20
• CPC Class Codes: H04N 25/773 comprising photon counting circuits, e.g. single photon detection [SPD] or single photon avalanche diodes [SPAD]

Abstract

An imaging detector system includes a radiation detector having a plurality of pixels for generating a plurality of detection signals in response to radiation. Each of the pixels is used to generate a corresponding one of the detection signals. The imaging detector system includes a plurality of photon counting channels. Each photon counting channel is coupled to a corresponding one of the pixels to receive and process the corresponding one of the detection signals. Each photon integrating channel is coupled to a corresponding one of the pixels to receive and process the corresponding one of the detection signals. An image processor receives outputs from the photon counting channels and the photon integrating channels, wherein the image processor is adapted to generate an image using the received outputs.

Claims

1. An imaging detector system comprising:

a radiation detector having a plurality of pixels for generating a plurality of detection signals in response to radiation, each of the pixels being used to generate a corresponding one of the detection signals;

a plurality of photon counting channels, each of the photon counting channels being coupled to a corresponding one of the pixels to receive and process the corresponding one of the detection signals;

a plurality of photon integrating channels, each of the photon integrating channels being coupled to a corresponding one of the pixels to receive and process the corresponding one of the detection signals; and

an image processor for receiving outputs from the photon counting channels and the photon integrating channels, wherein the image processor is adapted to generate an image using the received outputs,

wherein corresponding ones of the photon counting and photon integrating channels concurrently receive a same one of the detection signals.

2. The imaging detector system of claim 1, wherein the corresponding ones of the photon counting and photon integrating channels concurrently process the same one of the detection signals.

3. The imaging detector system of claim 1, wherein the photon counting channels are adapted to generate a digital output corresponding to a number of photons detected by the corresponding one of the pixels.

4. The imaging detector system of claim 1, wherein the photon counting channels are adapted to generate digital outputs corresponding to both number of photons and energies carried by these photons detected by the corresponding one of the pixels.

5. The imaging detector system of claim 1, further comprising means for configuring the system to operate in either a photon counting mode or a photon integrating mode.

6. The imaging detector system of claim 5, wherein said configuring means is adapted to switch the system between the photon counting mode and the photon integrating mode in accordance with a feedback signal from the image processor.

7. The imaging detector system of claim 5, wherein said configuring means comprises an impedance network being switchable between the photon counting mode and the photon integration mode.

8. The imaging detector system of claim 7, wherein the impedance network comprises a plurality of resistors and at least one capacitor in parallel, wherein at least one of the resistors or the capacitor is selectively connected or disconnected in response to a feedback signal from the image processor.

9. The imaging detector system of claim 5, wherein said configuring means is adapted to configure particular ones of the channels to be in a photon integrating mode when a photon counting mode is saturated.

10. The imaging detector system of claim 1, wherein the radiation comprises x-rays.

11. The imaging detector system of claim 1, wherein at least one of the photon integrating channels is adapted to be concurrently calibrated with at least one of the photon counting channels.

12. The imaging detector system of claim 1, further comprising a computer for further processing an image generated by the image processor, and an image display for displaying the image.

13. An imaging detector system comprising:

a radiation detector having a plurality of pixels for generating a plurality of detection signals in response to radiation, each of the pixels being used to generate a corresponding one of the detection signals;

a plurality of photon counting channels, each of the photon counting channels being coupled to a corresponding one of the pixels to receive and process the corresponding one of the detection signals;

a plurality of photon integrating channels, each of the photon integrating channels being coupled to a corresponding one of the pixels to receive and process the corresponding one of the detection signals;

an image processor for receiving outputs from the photon counting channels and the photon integrating channels, wherein the image processor is adapted to generate an image using the received outputs; and

a switch for providing the detection signals to the photon counting channels or to the photon integrating channels.

14. The imaging detector system of claim 13, wherein the switch comprises a plurality of switches, each of the switches being adapted to provide a corresponding one of the detection signals to a corresponding one of the photon counting channels or a corresponding one of the photon integrating channels.

15. The imaging detector system of claim 14, wherein each of the switches is adapted to provide the corresponding one of the detection signals to the corresponding one of the photon counting channels or to the corresponding one of the photon integrating channels, in accordance with whether the corresponding one of the photon counting channels is saturated.

16. The imaging detector system of claim 15, wherein the image processor provides a feedback signal to at least one of the switches to indicate that the corresponding one of the photon counting channels is saturated.

17. The imaging detector system of claim 13, wherein the radiation comprises x-rays.

18. An imaging detector system comprising:

a photon counting detector having a plurality of first pixels for generating a plurality of first detection signals in response to radiation, each of the first pixels being used to generate a corresponding one of the first detection signals;

a photon integrating detector having a plurality of second pixels for generating a plurality of second detection signals in response to the radiation, each of the second pixels being used to generate a corresponding one of the second detection signals;

a plurality of photon counting channels, each of the photon counting channels being coupled to a corresponding one of the first pixels to receive and process the corresponding one of the first detection signals;

a plurality of photon integrating channels, each of the photon integrating channels being coupled to a corresponding one of the second pixels to receive and process the corresponding one of the second detection signals; and

an image processor for receiving outputs from the photon counting channels and the photon integrating channels, wherein the image processor is adapted to generate an image using the received outputs.

19. The imaging detector system of claim 18, wherein the photon counting detector and the photon integrating detector are disposed one on top of another.

20. The imaging detector system of claim 18, wherein the photon counting detector receives the radiation first, and the photon integrating detector receives a portion of the radiation that passes through the photon counting detector.

21. The imaging detector system of claim 20, wherein the photon counting channels and photon integrating channels are adapted to generate digital outputs corresponding to both intensity of photons and energies carried by these photons detected by the corresponding pixels.

22. The imaging detector system of claim 18 wherein the radiation comprises x-rays.