Abstract:
:Absolute speeds (mR-1) of screen-film systems were determined accurately and precisely from ten independent measurements over a six month period at several beam qualities that included both scatter and scatter-free conditions. The absorbed x-ray energies in the screens that yielded a net film density of 1.0 were obtained by means of Monte Carlo calculations and a semianalytical method. The standard deviations of the calculated absorbed x-ray energies at different beam qualities were less than 10% for all of the screen-film systems studied. Therefore, the absorbed x-ray energy that produces a given film density for these systems can be regarded as constant at the beam qualities used. Quantum absorption and fractional energy absorption of the screens were also calculated. The predicted Wiener spectral values based on the number of photons detected were compared with the measured Wiener spectral values of the screen-film systems.
journal_name
Radiologyjournal_title
Radiologyauthors
Kodera Y,Doi K,Chan HPdoi
10.1148/radiology.151.1.6701320subject
Has Abstractpub_date
1984-04-01 00:00:00pages
229-36issue
1eissn
0033-8419issn
1527-1315journal_volume
151pub_type
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