Australian Optical Society

Glass-Ceramic Based X-Ray Storage Phosphors

G. V. M. WILLIAMS,
Industrial Research Limited, P.O. Box 31310, Lower Hutt, New Zealand.

A. EDGAR,
School of Chemical and Physical Sciences, Victoria University, Wellington, New Zealand.

J. –M. SPAETH and S. SCHWEIZER,
Department of Physics, University of Paderborn, Germany.

X-Ray Storage phosphors can replace the photographic film traditionally used for medical and industrial radiography. They have the advantages of a vastly increased dynamic range of contrast, are re-useable, and are readily interfaced to computers for image enhancement processing. These solid state phosphors store an X-ray image as a concentration of radiation-created trapped electrons and holes. The electrons and holes can be stimulated to recombine during a raster scan of a phosphor screen by a red "read-out" laser beam; the energy of recombination is given off as blue light which is detected by a photomultiplier.

We have identified glass-ceramics based on a fluorozirconate glass which shows a significant X-ray storage effect. The properties and characteristics of this glass ceramic will be described and compared with existing single crystal materials.  Specifically we will discuss the results from annealing studies, photo-luminescence measurements, photo-stimulated luminescence measurements, thermo-stimulated luminescence measurements, electron spin resonance and optical absorption measurements.