INTEGRATED SIDE-BY-SIDE PIXEL-ARRAY SENSOR FOR X-RAY BOTH DUAL-ENERGY AND EXTENDED DYNAMIC RANGE SINGLE-ENERGY

Abstract

A radiation image detector comprises two parallel rows of one dimensional pixel arrays in a single substrate so that the two pixel arrays are precisely aligned and spaced. Each pixel in one pixel array has a corresponding pixel in the other pixel array. Two arrays are responsive to radiation with different sensitivity by applying different scintillating material. When an object moves perpendicular to the both pixel arrays under radiation flux, two sets of correlated radiation images will be generated. By applying software image merging technique, dynamic range can be extended. If a filter material is placed in front of pixel array with more sensitivity then it then becomes a standard dual-energy detector. The pixel array with filter is high-energy (HE) detector and the other array is low-energy (LE) detector.

Claims

1. A radiation detector comprising: a first element array responsive to radiation to provide a first radiation response; a second element array responsive to radiation with different sensitivity to provide a second radiation response, the second element array being positioned to receive radiation independently of the first element array, the first and second element array placed parallel to each other in the same substrate.

2. The radiation detector of claim 1, wherein each said element array comprises: A scintillating material layer and a sensor array coupled to the scintillating material layer to provide an indication of the corresponding radiation response.

3. The radiation detector of claim 1, wherein photodiode detectors have peripheral circuits comprising pixel signal processing circuits, global video signal processing circuits and timing generators which generate all control clocks necessary for operation of the detectors.

4. The radiation detector of claim 1, wherein it includes time-delayed integration TDI type detector.

5. The radiation detector of claim 2, wherein said indication is a video signal.

6. A radiation detector comprising: a first element array responsive to radiation to provide a first radiation response; a second element array responsive to radiation with different sensitivity to provide a second radiation response, the second element array being positioned to receive radiation independently of the first element array, the first and second element array placed parallel to each other in the same substrate; a filter coupled to the second element to enhance the second radiation response independently of the first radiation response.

7. The radiation detector of claim 6, wherein each said element array comprises: A scintillating material layer and a sensor array coupled to the scintillating material layer to provide an indication of the corresponding radiation response.

8. The radiation detector of claim 6, wherein photodiode detectors have peripheral circuits comprising pixel signal processing circuits, global video signal processing circuits and timing generators which generate all control clocks necessary for operation of the detectors.

9. The radiation detector of claim 6, wherein said filter includes metal, plastic and composite material.

10. The radiation detector of claim 6, wherein it includes time-delayed integration (TDI) type detector.

11. The radiation detector of claim 7, wherein said indication is a video signal.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1 shows a typical dual energy application in which two side-by-side arrays and processing circuits are in a single substrate.

[0027] FIG. 2 shows two linear arrays and their processing circuit in a single substrate.

[0028] FIG. 3 shows a basic side-by-side dual energy X-ray detector in a single substrate after shielding and filter are in place.

[0029] FIG. 4 shows a long side-by-side X-ray detector can be achieved by cascading multiple basic detectors.

[0030] FIG. 5 shows two linear arrays and their processing circuit in separate substrate.

[0031] FIG. 6 shows a dual energy application in which two side-by-side arrays and processing circuits are in separate substrates.

[0032] FIG. 7 shows a basic single energy detector with extended dynamic range in separate substrates after shielding is in place.

[0033] FIG. 8 shows a typical single energy application with extended dynamic range in which two side-by-side arrays and processing circuits are in a single substrate.

[0034] FIG. 9 shows a single energy application with extended dynamic range in which two side-by-side arrays and processing circuits are in separate substrates.

[0035] FIG. 10 shows an advanced pixel binning feature of the current invention where two different pixel sizes can be achieved in one setup.

DETAILED DESCRIPTION OF THE INVENTION

[0036] The present invention is a versatile X-ray linear detector. This detector has a precise side-by-side configuration of two row sensor pixel arrays 13. This has dual functionalities. With an external filter material 11, it serves a dual energy detector; without filter material 11, it can extend dynamic range for a single energy X-ray detector.

[0037] For the side-by-side configuration detector to work with different pixel sizes, two sensor pixel arrays 13 must be precisely arranged in the same pixel array substrate 14 so that two arrays are precisely parallel and distance between two corresponding pixels are precisely the same.

[0038] Signal processing circuit 9 can be in the same pixel array substrate 14, or can be in a different substrate as processing circuit substrate 10. Two sensor pixel arrays 13 are attached with two kinds of scintillating material. One with more sensitive scintillating material 4, the other array is with less sensitive scintillating material 5.

[0039] FIG. 1 shows a typical implementation of a side-by-side dual energy application when two sensor pixel arrays 13 and processing circuit 9 in a single integrated sensor substrate 8.

[0040] X-ray source 1 generates X-ray beam 2. When scan objects 3 pass through X-ray beam 2, the image signal will be registered in the two parallel sensor pixel arrays 13. Usually shielding material 12 is needed to protect processing circuit 9.

[0041] External filter material 11 is placed in front of the array with more sensitive scintillating material 4, so this array is also called high energy sensor array 6; the array with less sensitive scintillating material 5 is also call low energy sensor array 7. In application, side-by-side configuration is not sensitive to direction of scan object 3 motion. Scan object 3 can either reach low energy sensor array 7 first or can reach high energy sensor array 6 first.

[0042] Referring to FIG. 2, two sensor pixel arrays 13 and processing circuit 9 are in a single integrated sensor substrate 8 are shown. Usually the single integrated sensor substrate 8 can be mounted in material like printed circuit board (PCB), glass etc

[0043] FIG. 3 shows a basic dual energy X-ray detector. Two sensor pixel arrays 13 and processing circuit 9 are in a single integrated sensor substrate 8. One array is attached with more sensitive scintillating material 4; the other array is attached with less sensitive scintillating material 5. External filter material 11 is placed in front of the array with more sensitive scintillating material 4. Shielding material 12 is needed to protect processing circuit 9. In this case, external filter material 11 and shielding material 12 are close to each other so that one option is to mount external filter material 11 on shielding material 12.

[0044] FIG. 4 shows that side-by-side x-ray detectors can be made to be buttable so that the detector can be cascaded to specific length. In this case, there is no limit on total length.

[0045] FIG. 5 shows two sensor pixel arrays 13 and processing circuit 9 in separate substrates. Two sensor pixel arrays 13 are in pixel array substrate 14; processing circuit 9 is in processing circuit substrate 10. Connection between sensor pixel arrays 13 and processing circuit 9 can be achieved through wire bonding on substrate.

[0046] FIG. 6 is an alternative implementation of a side-by-side dual energy application when two sensor pixel arrays 13 and processing circuit 9 in separate substrates.

[0047] FIG. 7 shows a basic dual row X-ray detector to extend dynamic range. Two sensor pixel arrays 13 and processing circuit 9 are in a single integrated sensor substrate 8. One array is attached with more sensitive scintillating material 4; the other array is attached with less sensitive scintillating material 5. Shielding material 12 is needed to protect processing circuit 9. In this case, no filter material 11 is needed.

[0048] FIG. 8 shows typical implementation of a side-by-side dual row linear detector to extend dynamic range when two sensor pixel arrays 13 and processing circuit 9 in a single integrated sensor substrate 8.

[0049] FIG. 9 shows an alternative implementation of a side-by-side row linear detector to extend dynamic range when two sensor pixel arrays 13 and processing circuit 9 in separate substrates.

[0050] FIG. 10 shows an advanced pixel binning feature over prior art. X-ray detector can run with two different pixel size modes can in one setup. In mode One, i.e. larger pixel mode: larger pixel size is equal to the sum of the first inner smaller pixel 15, the second smaller pixel 16 and one outer larger pixel 17; in mode Two, i.e. smaller pixel mode: data acquisition ignores the outer larger pixel, and only cares about the data from inner smaller pixels.

[0051] The above disclosure is not intended as limiting. Those skilled in the art will readily observe that variations and alterations of the device may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the restrictions of the following claims.