Abstract：
:System modeling is used to investigate the effect of various system parameters on the image quality in CCD-based x-ray imaging systems. The systems considered consist of a typical phosphor-based scintillating screen coupled to a CCD through lens or fiberoptic taper. Two applications, chest radiography and mammography, are analyzed. For each application typical system characteristics and operating conditions are used to determine the detective quantum efficiency (DQE) as a function of spatial frequency, optical collection efficiency, optical demagnification factor, and electronic noise. The DQE is modeled by extending the analysis for storage phosphor systems. The calculations are done for typical exposure conditions (0.25 mR for chest and 10.0 mR for mammography); however, the exposure effects are also discussed. It was found that a reasonable DQE can be obtained for both applications through each coupling approach; however, the demagnification requirements and electronic noise limitations are more stringent for the digital mammography application.
journal_name
Med Physjournal_title
Medical physicsauthors
Hejazi S,Trauernicht DPdoi
10.1118/1.598072subject
Has Abstractpub_date
1997-02-01 00:00:00pages
287-97issue
2eissn
0094-2405issn
2473-4209journal_volume
24pub_type
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