Thermal sensing detector cell for a computed tomography system and method of manufacturing same

• US 6,654,443 B1
• Filed: 02/25/2002
• Issued: 11/25/2003
• Est. Priority Date: 02/25/2002
• Status: Expired due to Term

• Current Assignee: GE Medical Systems Global Technology Company LLC (GE Healthcare Technologies, Inc.)
• Original Assignee: GE Medical Systems Global Technology Company LLC (GE Healthcare Technologies, Inc.)
• Inventors: Hoffman, David M.
• Primary Examiner(s): MCCALL, ERIC SCOTT
• Application Number:
  US09/683,869
• Time in Patent Office: 638 Days
• Field of Search: 378/19, 250/370.01, 250/370.08, 250/370.09
• US Class Current: 378/19
• CPC Class Codes: G01T 1/2985 In depth localisation, e.g. using positron emitters; Tomographic imaging (longitudinal and transverse section imaging; apparatus for radiation diagnosis sequentially in different planes, steroscopic radiation diagnosis); using external radiation sources A61B6/02
• CPC Class Codes: G01V 5/226 using tomography

Abstract

The present invention provides a detector cell having an x-ray absorption component and a thermal sensing component configured to detect thermal differentials in the absorption component resulting from the absorption of x-rays. The absorption component comprises high density materials that respond thermally to the reception of x-rays or other HF electromagnetic energy. The thermal sensing component detects the changes in temperature of the absorption component and outputs electrical signals indicative of the number and intensity of the x-rays absorbed. An image reconstructor then processes those electrical signals to reconstruct an image of the subject scanned. A method of manufacturing the detector cell is also provided.

Claims

1. A CT detector cell comprising:

a high frequency (HF) electromagnetic energy absorption component comprised of a material configured to change in temperature in response to absorption of HF electromagnetic energy; and

a thermal sensing component configured to detect changes in temperature of the absorption component and output a signal indicative of the HF electromagnetic energy absorbed by the HF electromagnetic energy absorption component based on the detected changes in temperature.

2. The CT detector cell of claim 1 wherein the material includes at least one of tungsten, lead, and tantalum.

3. The CT detector cell of claim 1 wherein the thermal sensing component is affixedly connected to the HF electromagnetic energy absorption component.

4. The CT detector cell of claim 1 wherein the thermal sensing component includes one of an IR thermal sensor and a microbolometer.

5. The CT detector cell of claim 4 wherein the microbolometer includes a room temperature microbolometer.

6. The CT detector cell of claim 1 incorporated as an array in at least one of a medical imaging device and a non-invasive package/baggage inspection device.

7. A CT system comprising;

a rotatable gantry having an opening therein and configured to receive an subject to be scanned;

a subject positioner configured to place the subject to be scanned within the opening;

an (HF) electromagnetic energy projection source configured to project HF electromagnetic energy toward the subject to be scanned;

an HF electromagnetic energy detector array having a plurality of detector cells and configured to absorb HF electromagnetic energy passing through the subject to be scanned, wherein each detector cell includes;

an HF electromagnetic energy absorption component; and

a thermal sensing component;

a data acquisition system (DAS) connected to the detector array and configured to receive electrical signals from each thermal sensing component indicative of a change in temperature of a corresponding HF electromagnetic energy absorption component; and

an image reconstructor connected to the DAS and configured to reconstruct an image of the subject from the electrical signals received by the DAS.

8. The CT system of claim 7 incorporated into a medical diagnostic imaging device wherein the subject positioner includes a movable table and the subject to be scanned includes a medical patient.

9. The CT system of claim 7 incorporated into a non-invasive package/baggage inspection device wherein the subject positioner includes a conveyor apparatus and the subject to be scanned includes at least one of a package and a piece of baggage.

10. The CT system of claim 9 incorporated into at least one of a postal inspection security system and an airport security system.

11. The CT system of claim 7 wherein the HF electromagnetic energy absorption component includes material that undergoes a change in temperature In response to absorption of HF electromagnetic energy.

12. The CT system of claim 7 wherein the thermal sensing component includes one of a night vision IR thermal sensor and a room temperature microbolometer.

13. The CT system of claim 7 wherein the HF electromagnetic energy detector array includes one of a pixilated and a columnar orientation.

14. The CT system of claim 7 further comprising a collimator to reduce HF electromagnetic energy scatter from the subject to be scanned.

15. A detector array for a CT imaging system, the detector array comprising:

means for absorbing high frequency (HF) electromagnetic energy;

means for experiencing thermal differentials in response to absorbed HF electromagnetic energy;

means for detecting the thermal differentials; and

means for outputting a signal indicative of the HF electromagnetic energy absorbed based on the detected thermal differentials.

16. A CT detector array comprising:

a plurality of high frequency (HF) electromagnetic energy absorption cells comprised of a material configured to change in temperature in response to absorption of HF electromagnetic energy; and

a plurality of thermal sensing cells to sense changes in temperature of the plurality of HF electromagnetic energy absorption cells and output a signal indicative of the HF electromagnetic energy absorbed by the HF electromagnetic energy absorption component based on the change in temperature of the HF electromagnetic energy absorption cells.

17. The CT detector array of claim 16 wherein the plurality of HF electromagnetic energy absorption cells comprises at least one of tungsten, lead, and tantalum.

18. The CT detector array of claim 16 incorporated into a CT imaging system comprising:

a rotatable gantry having an opening therein and configured to receive an subject to be scanned;

a subject positioner configured to place the subject to be scanned within the opening;

a HF electromagnetic energy projection source configured to project HF electromagnetic energy toward the subject to be scanned;

a data acquisition system (DAS) configured to receive electrical signals from each thermal sensing cell; and

an image reconstructor connected to the DAS and configured to reconstruct an image of the subject from the electrical signals received by the DAS.

19. The CT detector array of claim 16 wherein each thermal sensing cell includes one of a night vision IR thermal sensor and a room temperature microbolometer.