BEAM DETECTION AND FILTERING NOISE

• US 20190310382A1
• Filed: 06/26/2017
• Published: 10/10/2019
• 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
• Granted Patent: US 10,732,301 B2
• Time in Patent Office: 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, the method comprising:

monitoring output signals of the detector;

detecting positive signals in the output signals;

not detecting negative signals in the output signals; and

determining that the detected positive signals are a result of x-rays impacting the imaging pixels based on said not detecting the negative signals.

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

measuring a magnitude of the detected positive signals; and

determining that the magnitude of the detected positive signals exceeds a preset positive threshold.

3. The method of claim 2, further comprising:

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

determining that the number of the detected positive signals whose magnitude exceeds the preset positive threshold exceeds a preset number threshold.

4. The method of claim 2, further comprising:

determining a mean magnitude of the detected positive signals for each of a preset number of vertically consecutive strips of pixels; and

determining that the mean magnitude of the detected positive signals for each of the preset number of vertically consecutive strips of pixels all exceed the preset positive threshold.

5. The method of claim 2, wherein the step of measuring further comprises determining a statistical measure of the magnitude of the detected positive signals.

6. 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 positive signals are the result of x-rays impacting the imaging pixels.

7. A method of operating a digital radiographic detector that includes a plurality of imaging pixels, the method comprising:

monitoring output signals of the detector;

detecting positive signals in the output signals;

detecting negative signals in the output signals; and

determining that the detected positive signals are not caused by x-rays impacting the imaging pixels in the detector based on said detecting the negative signals.

8. The method of claim 7, 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 less than a preset negative threshold.

9. The method of claim 8, further comprising:

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

determining that the number of the detected negative signals whose magnitude are less than the preset negative threshold exceeds a preset number threshold.

10. The method of claim 8, further comprising:

determining a mean magnitude of the detected negative signals for each of a preset number of vertically consecutive strips of pixels; and

determining that the mean magnitude of the detected negative signals for each of the preset number of vertically consecutive strips of pixels all are less than the preset negative threshold.

11. The method of claim 8, wherein the step of measuring further comprises determining a statistical measure of the magnitude of the detected negative signals.

12. The method of claim 7, 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 the detected positive signals are not caused by x-rays impacting the imaging pixels.