Radiation detector head

• US 20060011852A1
• Filed: 07/14/2005
• Published: 01/19/2006
• Est. Priority Date: 07/14/2004
• Status: Active Grant

• Current Assignee: Orbotech Limited (KLA Corporation)
• Original Assignee: Orbotech Medical Solutions Ltd. (General Electric Company)
• Inventors: Shahar, Arie, El-Hanany, Uri, Tsigelman, Alex
• Granted Patent: US 7,339,176 B2
• Time in Patent Office: Days
• US Class Current: 250/370.90
• CPC Class Codes: G01T 1/243 Modular detectors, e.g. arrays formed from self contained units constructional or manufacturing details H01L25/00
• CPC Class Codes: G01T 1/2928 using solid state detectors

Abstract

A radiation detection camera head having a focal-plane array of pixelated detectors having constant pitch between pixels over the whole of the camera head, while using detector modules having normal production tolerances, and which can nevertheless be readily removed and replaced in the detector array by means of predetermined gaps between adjacent detector modules. The pixels on the side walls of the detector modules have reduced size to maintain constant pitch over the array in spite of production variation between modules. The reduction in sensitivity due to this reduced size is compensated for by the addition of insulated conductive bands on the side walls. The head collimator is such that the septa fall between pixels and between modules, such that head sensitivity is maintained at its optimum value.

Claims

1. A radiation detector camera head comprising an array of at least two pixelated detector modules mounted in said head, said modules comprising pixels and having side walls,

wherein each of said at least two modules has module lateral dimensions, said modules being mounted at a pitch at least equal to the largest module lateral dimension of any of said at least two modules, such that a gap exists between said side walls of an adjacent pair of said at least two modules, and

wherein said pixels on said modules not located adjacent to said side walls have first lateral dimensions, and at least some of said pixels disposed along said side walls have second lateral dimensions smaller than said first lateral dimensions.

2. A radiation detector camera head according to claim 1, and wherein any one of said adjacent pair of modules is at least one of removable from or insertable into said head, without interference from the other of said adjacent pair.

3. A radiation detector camera head according to claim 1, and wherein said gap between said modules compensates dimensionally for said second lateral dimensions being smaller than said first lateral dimensions, such that an essentially constant pitch is maintained between said pixels across said array.

4. A radiation detector camera head according to claim 3, and wherein said constant pitch between said pixels is operative to reduce deformation of images acquired by said camera.

5. A radiation detector camera head according to claim 1, and wherein said module lateral dimension varies according to a first production tolerance of said module and has a first maximum permitted value, and wherein said gap is at least twice as large as said first maximum permitted value.

6. A radiation detector camera head according to claim 5, and wherein said at least two modules are mounted in said camera head by means of mounting hardware, said mounting hardware also varying in lateral dimension according to a second production tolerance and having a second maximum permitted value, and wherein said gap is at least twice as large as a sum of said first and second maximum permitted values.

7. A radiation detector camera head comprising an array of at least two pixelated detector modules mounted in said head, said modules comprising pixels and having side walls,

wherein each of said at least two modules has module lateral dimensions, said modules being mounted at a pitch at least equal to the largest module lateral dimension of any of said at least two modules, such that a gap exists between said side walls of an adjacent pair of said at least two modules, and

wherein the pixels on said modules not located adjacent to a side wall have first lateral dimensions, and at least some of said pixels disposed along said side walls have second lateral dimensions smaller than said first lateral dimensions, and

wherein said camera head also comprises a collimator having multiple holes, said holes being arranged in a pitch generally equal to the pitch of said pixels of said modules and said holes being spaced by septa, and

wherein said collimator is arranged such that said septa fall in a region between said detector pixels.

8. A radiation detector camera head according to claim 7, and wherein said collimator and said modules are arranged such that said septa also fall on said gaps between said modules.

9. A radiation detector camera head according to claim 7, and wherein said camera head reduces detection loss due to dead areas in said array.

10. A radiation detector camera head according to claim 7, and wherein any one of said adjacent pair of modules is at least one of, removable from or insertable into said head, without interference from the other of said adjacent pair.

11. A radiation detector camera head according to claim 7, and wherein said gap between said modules compensates dimensionally for said second lateral dimensions being generally smaller than said first lateral dimensions, such that an essentially constant pitch is maintained between said pixels across said array

12. A radiation detector camera head according to claim 11, and wherein said constant pitch between said pixels is operative to reduce deformation of images acquired by said camera.

13. A radiation detector camera head according to claim 7, and wherein said module lateral dimensions vary according to a first production tolerance of said modules and have a first maximum permitted value, and wherein said gap is at least twice as large as said first maximum permitted value.

14. A radiation detector camera head according to claim 13, and wherein said at least two modules are mounted in said camera head by means of mounting hardware, said mounting hardware also varying in lateral dimensions according to a second production tolerance and having a second maximum permitted value, and wherein said gap is at least twice as large as a sum of said first and second maximum permitted values.

15. A radiation detector camera head comprising an array of at least two pixelated detector modules mounted in said head, said modules comprising pixels and having side walls, and

wherein each of said at least two modules has module lateral dimensions, said modules being mounted at a pitch at least equal to the largest module lateral dimension of any of said at least two modules, such that a gap exists between an adjacent pair of said at least two modules, and

wherein said pixels on said modules not located adjacent to said side walls have first lateral dimensions, and at least some of said pixels disposed along said side walls have second lateral dimensions smaller than said first lateral dimensions, and

wherein said camera head also comprises an insulated conductive band applied to at least one of said side walls of at least one of said modules, such as to compensate for reduced sensitivity arising from said smaller lateral dimensions of said pixels disposed along said at least one side wall.

16. A radiation detector camera head according to claim 15, and wherein said gap is sufficiently large also to accommodate said insulated conductive band.

17. A radiation detector camera head according to claim 15, and wherein any one of said adjacent pair of modules is at least one of removable from or insertable into said head, without interference from the other of said adjacent pair.

18. A radiation detector camera head according to claim 15, and wherein said gap between said modules compensates dimensionally for said second lateral dimensions being smaller than said first lateral dimensions, such that an essentially constant pitch is maintained between said pixels across said array.

19. A radiation detector camera head according to claim 18, and wherein said constant pitch between said pixels is operative to reduce deformation of images acquired by said camera.

20. A radiation detector camera head according to claim 15, and wherein said module lateral dimensions vary according to a first production tolerance of said modules and has a first maximum permitted value, and wherein said gap is at least twice as large as said first maximum permitted value.

21. A radiation detector camera head according to claim 20, and wherein said at least two modules are mounted in said camera head by means of mounting hardware, said mounting hardware also varying in lateral dimension according to a second production tolerance and having a second maximum permitted value, and wherein said gap is at least twice as large as a sum of said first and second maximum permitted values.

22. A radiation detector camera head according to claim 15, and also comprising a collimator having multiple holes, said holes being arranged in a pitch equal to the pitch of said pixels of said modules and being spaced by septa, and said collimator being arranged such that said septa fall in a region between said detector pixels.

23. A radiation detector camera head according to claim 22, and wherein said collimator and said modules are arranged such that said septa also fall on said gaps between said modules.

24. A radiation detector camera head according to claims 22, and wherein said camera head reduces detection loss due to dead areas in said array.

25. A method for producing a radiation detector camera head, comprising:

providing at least two pixelated detector modules, said modules having side walls and comprising pixels, wherein said pixels on said modules not located adjacent to said side walls have first lateral dimensions, and at least some of said pixels disposed along said side walls have second lateral dimensions smaller than said first lateral dimensions; and

mounting an array of said at least two pixelated detector modules in said head, wherein each of said at least two modules has module lateral dimensions, said modules being mounted at a pitch at least equal to the largest module lateral dimension of any of said at least two modules, such that a gap exists between an adjacent pair of said at least two modules.

26. A method for producing a radiation detector camera head, comprising:

providing at least two pixelated detector modules, said modules having side walls and comprising pixels, wherein said pixels on said modules not located adjacent to said side walls have first lateral dimensions, and at least some of said pixels disposed along said side walls have second lateral dimensions smaller than said first lateral dimensions;

mounting an array of said at least two pixelated detector modules in said head, wherein each of said at least two modules has module lateral dimensions, said modules being mounted at a pitch at least equal to the largest module lateral dimension of any of said at least two modules, such that a gap exists between an adjacent pair of said at least two modules; and

applying to a surface of the array a collimator having multiple holes, said holes being arranged in a pitch equal to the pitch of said pixels of said modules and said holes being spaced by septa, so that said septa fall in a region between said detector pixels.

27. A method for producing a radiation detector camera head, comprising:

providing at least two pixelated detector modules, said modules having side walls and comprising pixels, wherein said pixels on said modules not located adjacent to said side walls have first lateral dimensions, and at least some of said pixels disposed along said side walls have second lateral dimensions smaller than said first lateral dimensions;

mounting an array of said least two pixelated detector modules in said head, wherein each of said at least two modules has module lateral dimensions, said modules being mounted at a pitch at least equal to the largest module lateral dimension of any of said at least two modules, such that a gap exists between an adjacent pair of said at least two modules; and

applying an insulated conductive band to at least one of said side walls of at least one of said modules, so as to compensate for a reduced sensitivity arising from said smaller lateral dimensions of said pixels disposed along said at least one side wall.