Realizing Simultaneous X-Ray Imaging and Dosimetry Using Phosphor-Based Detectors with High Memory Stability and Convenient Readout Process

摘要

Flexible X-ray storage phosphor sheets are regarded as promising alternativesto conventional electronic flat-panel X-ray detectors, enabling X-ray imagingand dosimetry in less accessible situations. However, it is a challenge todevelop phosphor-based detectors with high memory stability and convenientreadout processes. Here, an approach to realize this using radiation-inducedphotoluminescence tuning in (Ba_(1-x)Sr_x)_2SiO_4:Eu phosphors is demonstrated,ascribed to the reduction of Eu~(3+) toward Eu~(2+). The associated photoluminescencespectral change and the accompanying color contrast in responseto the radiation dose are exploited for simultaneous X-ray dosimetry andimaging. The recorded image can be read out conveniently by a regular photocamera upon UV illumination and the radiation dose can be extracted duringthe imaging process in a ratiometric way via the green to red pixel intensity,avoiding the need for absolute intensity measurement. Moreover, theimaged information can be maintained for longer than 28 days and the platecan be reused for X-ray detection after bleaching upon 420 nm illumination,exhibiting superior memory retention ability and good cycling resistance.These results reveal the great potential of (Ba_(1-x)Sr_x)_2SiO_4:Eu for X-ray-basedmicrobeam radiation therapy and nondestructive inspection and are expectedto stimulate research on phosphor-based photoluminescence modulateddetectors.