Beam detection and filtering noise

• US 10,732,301 B2
• Filed: 06/26/2017
• Issued: 08/04/2020
• Est. Priority Date: 06/27/2016
• Status: Active Grant

• Current Assignee: CareStream Health Incorporated
• Original Assignee: CareStream Health Incorporated
• Inventors: Scott, Richard T., Welch, Eric M., Toepfer, Karin
• Primary Examiner(s): Porta, David P
• Assistant Examiner(s): Sahu, Meenakshi S
• Application Number:
  US16/309,509
• Publication Number:
  US 20190310382A1
• Time in Patent Office: 1,135 Days
• CPC Class Codes: A61B 6/42 Arrangements for detecting radiation specially adapted for radiation diagnosis
• CPC Class Codes: A61B 6/50 specially adapted for specific body parts; specially adapted for specific clinical applications
• CPC Class Codes: A61B 6/54 Control of apparatus or devices for radiation diagnosis
• CPC Class Codes: G01T 1/1663 Processing methods of scan data, e.g. involving contrast enhancement, background reduction, smoothing, motion correction, dual radio-isotope scanning, computer processing for measuring spatial distribution of radiation G01T1/2992; general purpose image data processing G06T1/00; computerized tomography G06T11/003; Ancillary equipment colour printers G01T1/1666
• CPC Class Codes: G01T 1/17 Circuit arrangements not adapted to a particular type of detector pulse-selection circuits H03K, G01R

Abstract

A digital radiographic detector outputs positive read out signals that may oscillate. The presence of negative going portions of the read out signals may be used to determine that the detected positive signals are a result of noise, while an absence of the negative going portions may be used to determine that x-rays are impacting the detector.

Claims

1. A method of operating a digital radiographic detector that includes a plurality of imaging pixels disposed in rows and columns, the method comprising:

monitoring an output signal from each of a plurality of individual adjacent strips of the imaging pixels of the detector, wherein the individual adjacent strips each consist of a preselected portion of one of a plurality of adjacent rows of the imaging pixels;

when detecting one or more only positive signals in the output signals that satisfy a preset positive threshold, determining that the detected one or more only positive signals are caused by x-rays impacting the imaging pixels; and

when detecting one or more negative signals in the output signals that satisfy a preset negative threshold, determining that any detected positive signals are not caused by x-rays impacting the imaging pixels.

2. The method of claim 1, wherein the step of detecting one or more only positive signals further comprises:

measuring a magnitude of the detected one or more only positive signals; and

determining that the magnitude of the detected one or more only positive signals satisfies the preset positive threshold.

3. The method of claim 2, further comprising:

determining a number of the detected one or more only positive signals whose magnitude satisfies the preset positive threshold; and

determining that the number of the detected one or more only positive signals whose magnitude satisfies the preset positive threshold also satisfies a preset number threshold.

4. The method of claim 2, wherein the step of measuring further comprises determining a statistical measure of the magnitude of the detected one or more only positive signals.

5. The method of claim 1, further comprising:

capturing radiographic image data in the detector; and

storing the captured radiographic image data for diagnostic purposes based upon the step of determining that the detected one or more only positive signals are caused by x-rays impacting the imaging pixels.

6. A method of operating a digital radiographic detector that includes a plurality of imaging pixels disposed in rows and columns, the method comprising:

monitoring output signals from each of a plurality of individual adjacent strips of the imaging pixels of the detector, wherein the individual adjacent strips each consist of a preselected portion of one of a plurality of adjacent rows of the imaging pixels;

when detecting only positive signals in the output signals that satisfy a preset positive threshold, determining that the detected positive signals are caused by x-rays impacting the imaging pixels; and

when detecting negative signals in the output signals that satisfy a preset negative threshold, determining that any detected positive signals are not caused by x-rays impacting the imaging pixels.

7. The method of claim 6, wherein the step of detecting negative signals further comprises:

measuring a magnitude of the detected negative signals; and

determining that the magnitude of the detected negative signals are greater than a preset negative threshold.

8. The method of claim 7, further comprising:

determining a number of the detected negative signals whose magnitude are greater than the preset negative threshold; and

determining that the number of the detected negative signals whose magnitude are greater than the preset negative threshold also satisfy a preset number threshold.

9. The method of claim 7, wherein the step of measuring further comprises determining a statistical measure of the magnitude of the detected negative signals.

10. The method of claim 6, further comprising:

capturing a frame of radiographic image data in the detector; and

discarding the frame of radiographic image data based upon the step of determining that any detected positive signals are not caused by x-rays impacting the imaging pixels.

11. A method of operating a digital radiographic detector that includes a plurality of imaging pixels disposed in rows and columns, the method comprising:

monitoring output signals from a plurality of imaging pixel windows, wherein the imaging pixel windows each consist of a portion of each of two or more adjacent rows of the imaging pixels;

when detecting only positive signals in the output signals that satisfy a preset positive threshold, determining that the detected only positive signals are caused by x-rays impacting the imaging pixels; and

when detecting negative signals in the output signals that satisfy a preset negative threshold, determining that any detected positive signals are not caused by x-rays impacting the imaging pixels.

12. The method of claim 11, wherein the step of detecting negative signals further comprises:

measuring a magnitude of the detected negative signals; and

determining that the magnitude of the detected negative signals are greater than a preset negative threshold.

13. The method of claim 12, further comprising:

determining a number of the detected negative signals whose magnitude are greater than the preset negative threshold; and

determining that the number of the detected negative signals whose magnitude are greater than the preset negative threshold also satisfy a preset number threshold.

14. The method of claim 12, wherein the step of measuring further comprises determining a statistical measure of the magnitude of the detected negative signals.

15. The method of claim 11, further comprising:

capturing a frame of radiographic image data in the detector; and

discarding the frame of radiographic image data based upon the step of determining that any detected positive signals are not caused by x-rays impacting the imaging pixels.

16. The method of claim 11, wherein the step of detecting only positive signals further comprises:

measuring a magnitude of the detected only positive signals; and

determining that the magnitude of the detected only positive signals satisfies the preset positive threshold.

17. The method of claim 16, further comprising:

determining a number of the detected only positive signals whose magnitude satisfies the preset positive threshold; and

determining that the number of the detected only positive signals whose magnitude satisfies the preset positive threshold also satisfies a preset number threshold.

18. The method of claim 16, wherein the step of measuring further comprises determining a statistical measure of the magnitude of the detected only positive signals.

19. The method of claim 11, further comprising:

capturing radiographic image data in the detector; and

storing the captured radiographic image data for diagnostic purposes based upon the step of determining that the detected only positive signals are caused by x-rays impacting the imaging pixels.