Focal spot position determiner
AssigneeAnalogic Corporation
InventorCharles Shaughnessy
Life of this patent
Estimating the term…
Abstract
One or more systems and/or techniques are disclosed herein for determining the orientation of a focal spot of a radiation source based upon shadows that are imposed on channels of a detector array from an anti-scatter grid. The anti-scatter grid is comprised of one or more anti-scatter plates that are focused on a point other than an intended focal spot of the radiation source. Such anti-scatters plates cast shadows on the detector array (even when the focal spot is located at the intended focal spot). By measuring changes in the signals generated by channels of the detector array that detect the shadows, it may be determined how the orientation of the focal spot has changed throughout an examination or between a calibration scan and an examination scan, for example.
Claims20
A radiography scanning apparatus, comprising:
- a radiation source configured to emit radiation;
- a detector array configured to detect the emitted radiation;
- and
- an anti-scatter grid comprised of a plurality of anti-scatter plates, wherein a first set of anti-scatter plates are focused on a point other than an intended focal spot of the radiation source, and wherein a second set of anti-scatter plates are focused on the intended focal spot, the second set different than the first set.
A method, comprising:
- receiving a signal that was generated by a calibration channel of a detector array during a calibration scan;
- receiving a signal that was generated by the calibration channel of the detector array during an examination scan;
- determining an orientation of a focal spot during the examination based on the signal that was generated by the calibration channel during the calibration scan and the signal that was generated by the calibration channel during the examination;
- receiving a signal that was generated by an imaging channel of the detector array during the examination;
- and
- correcting at least one of the signal that was generated by the imaging channel during the examination and projection data yielded from the signal that was generated by the imaging channel during the examination, the correction based upon the determined orientation of the focal spot during the examination.
The method of 12, wherein determining comprises comparing the signal generated by the calibration channel during the calibration scan with the signal generated by the calibration channel during the examination.
A radiography scanning apparatus, comprising:
- a radiation source configured to emit radiation;
- an anti-scatter grid comprised of at least first and second sets of anti-scatter plates, the first set comprising anti-scatter plates that are focused on a point other than an intended focal spot of the radiation source and the second set comprising anti-scatter plates that are focused on the intended focal spot of the radiation source;
- a detector array configured to detect the emitted radiation, the detector array comprising calibration channels and imaging channels, respective calibration channels positioned in close spatial proximity to an anti-scatter plate that is focused on the point other than the intended focal spot of the radiation source and respective imaging channels positioned in close spatial proximity to an anti-scatter plate that is focused on the intended focal spot of the radiation source, the calibration channels respectively configured to generate signals indicative of an orientation of a focal spot;
- and
- a correction component configured to identify a change in the orientation of the focal spot between a calibration scan and an examination based upon the signals generated by the calibration channels.
Dependencies are inferred from the claim text.