Share Email Print

Proceedings Paper

X-ray tube focal spot size, digital detectors, imaging system aperture and spatial resolution
Author(s): Edward L. Nickoloff
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Most modern radiology facilities are all digital, and film is not available for physics QC testing. An important test is the measurement of the effective focal spot sizes of the x-ray tube which has an impact on overall image system spatial resolution. Focal spot size measurements typically utilize a star pattern which is magnified and recorded on plain film. Plain film is ideal because it has a spatial resolution of 50-75 LP/mm. Utilizing digital image receptors to record the star pattern images does degrade the measurement because of the size of the individual detector elements (DEL). This article presents a method for the determination of focal spot size using the digital image receptor (DIR) to record the image of the star pattern. An equation which corrects for the image blur introduced by the finite size of the digital detector is given. Measurements of effective focal spot sizes are still important to the assessment of radiographic spatial resolution.

Paper Details

Date Published: 6 March 2013
PDF: 10 pages
Proc. SPIE 8668, Medical Imaging 2013: Physics of Medical Imaging, 86685S (6 March 2013); doi: 10.1117/12.2005964
Show Author Affiliations
Edward L. Nickoloff, Columbia Univ. (United States)
Columbia Univ. Medical Ctr. of New York-Presbyterian Hospital (United States)

Published in SPIE Proceedings Vol. 8668:
Medical Imaging 2013: Physics of Medical Imaging
Robert M. Nishikawa; Bruce R. Whiting; Christoph Hoeschen, Editor(s)

© SPIE. Terms of Use
Back to Top