Radiation imaging device with an array of image cells

• US 6,248,990 B1
• Filed: 10/10/1997
• Issued: 06/19/2001
• Est. Priority Date: 10/15/1996
• Status: Expired due to Term

• Current Assignee: Siemens Healthcare GMBH (Siemens AG)
• Original Assignee: Simage OY
• Inventors: Spartiotis, Konstantinos Evangelos, Pyyhtiä, Jouni Ilari
• Primary Examiner(s): Lee, John R.
• Application Number:
  US08/948,778
• Time in Patent Office: 1,348 Days
• Field of Search: 250/208.1, 250/208.2, 250/208.3, 250/208.4, 250/208.5, 250/231.1, 250/574, 250/328, 250/366, 250/369, 250/370.01, 250/370.02, 250/370.03, 250/370.06, 250/370.07, 250/370.08, 250/370.09, 250/370.11, 250/370.14, 378/62, 378/63, 378/98.8, 378/98.9, 378/98.11, 378/98.12
• US Class Current: 250/208.1
• CPC Class Codes: G01T 1/247 Detector read-out circuitry for processing gain or off-set correction H04N

Abstract

A radiation imaging device includes an image cell array having an array of detector cells and an array of image cell circuits. Each image cell circuit is associated with a respective detector cell and includes counting. The image cell circuits may include threshold circuitry configured to receive signals generated in the respective detector cell and having values dependent on the incident radiation energy. The counting circuitry may be coupled to the threshold circuitry.

Claims

1. A semiconductor imaging device including an imaging substrate comprising an image cell array of detector cells, each detector cell corresponding to an individual pixel of said image cell array, and which directly generate charge in response to incident high energy radiation, and a counting substrate containing an array of image cell circuits, each image cell circuit being associated with a respective detector cell, said image cell circuit comprising counting circuitry coupled to said respective detector cell, and configured to count plural radiation hits incident on said respective detector cell, wherein the counting substrate is directly connected to the imaging substrate by bump-bonds.

2. The imaging device of claim 1, wherein said image cell circuit comprises threshold circuitry coupled to receive signals generated in said respective detector cell and having values dependent on incident radiation energy, said counting circuitry being coupled to said threshold circuitry and being responsive to radiation hits within a predetermined energy range.

3. The imaging device of claim 2, wherein said threshold circuitry comprises first and second comparators configured to compare an input signal value to respective upper and lower threshold values.

4. The imaging device of claim 3, wherein said counting circuitry is configured to count radiation hits having an energy which generates an input signal value between said upper and lower threshold values.

5. The imaging device of claim 4, wherein said counting circuitry comprises trigger circuitry responsive to outputs of said first and second comparators, said trigger circuitry being configured to increment a counter in response to said input signal value.

6. The imaging device of claim 5, wherein said trigger circuitry comprises a flip-flop having a clock input coupled via a delay circuit to an output of said second comparator, a data signal input coupled via a one-shot circuit to an output of said first comparator, and an output coupled to said counter.

7. The imaging device of claim 6, wherein said image cell circuit further comprises a loadable shift register, said output of said counter being coupled to said loadable shift register, and said loadable shift register being chained with respective shift registers of other image cell circuits of said image cell circuit array.

8. The imaging device of claim 4, further comprising a first counter responsive to an output of said first comparator and a second counter responsive to an output of said second comparator.

9. The imaging device of claim 8, wherein an output of said first counter is coupled to a first loadable shift register, and said output of said second counter is coupled to a second loadable shift register, said first and second loadable shift registers being chained together and with respective loadable shift registers of other image cell circuits of said image cell circuit array.

10. The imaging device of claim 7, wherein said loadable shift registers are coupled to an output shift register arrangement external to said image cell circuit array.

11. The imaging device of claim 10, wherein said output shift register comprises a dual x-y configuration.

12. The imaging device of claim 1, wherein said image cell array is a pixel cell array.

13. A semiconductor radiation imaging system including a high energy radiation imaging device, said high energy radiation imaging device including an imaging substrate comprising an image cell array including an array of detector cells which directly generate charge in response to incident radiation and a counting substrate containing an array of image cell circuits, each image cell circuit being associated with a respective detector cell, said image cell circuit comprising counting circuitry coupled to said respective detector cell and configured to count plural radiation hits incident on said respective detector cell, wherein the counting substrate is directly connected to the imaging substrate by bump-bonds.

14. A method for high energy radiation imaging using a semiconductor radiation imaging device including an imaging substrate comprising an image cell array, the image cell array having an array of detector cells and a counting substrate containing an array of image cell circuits, wherein each detector cell is coupled to a corresponding image cell circuit, wherein the imaging substrate is directly connected to the counting substrate by bump-bonds, said method comprising the steps of:

directly generating charge in response to a radiation hit on a detector cell;

counting radiation hits incident on said detector cell in a corresponding image cell circuit.

15. The method of claim 14, wherein said counting step further comprises counting only radiation hits which generate charge within a predetermined energy range.

16. A semiconductor radiation imaging device including an imaging substrate comprising an image cell array of detector cells which directly generate charge in response to incident high energy radiation, and a counting substrate containing an array of image cell circuits, each image cell circuit being associated with and proximal to a respective detector cell, said image cell circuit comprising counting circuitry coupled to said respective detector cell and configured to count plural radiation hits incident on said respective detector cell, wherein the imaging substrate is directly connected to the counting substrate by bump-bonds.

17. The imaging device of claim 16, wherein said image cell circuit comprises threshold circuitry coupled to receive signals generated in said respective detector cell and having values dependent on incident radiation energy, said counting circuitry being coupled to said threshold circuitry and being responsive to radiation hits within a predetermined energy range.

18. A semiconductor radiation imaging system including a high energy radiation imaging device, said high energy radiation imaging device including an imaging substrate comprising an array of detector cells which directly generate charge in response to incident radiation and a counting substrate containing an array of image cell circuits, each image cell circuit being associated with a respective detector cell, said image cell circuit comprising counting circuitry proximally coupled to said respective detector cell and configured to count plural radiation hits incident on said respective detector cell, wherein the imaging substrate is directly connected to the counting substrate by bump-bonds.

19. A semiconductor imaging device including a semiconductor substrate comprising an image cell array of detector cells which directly generate charge in response to incident high energy radiation, the semiconductor substrate further including an array of image cell circuits, each image cell circuit being associated with a respective detector cell, said image cell circuit comprising counting circuitry coupled to said respective detector cell and configured to count plural radiation hits incident on said respective detector cell.