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

Abstract

Flexible X‐ray storage phosphor sheets are regarded as promising alternatives to conventional electronic flat‐panel X‐ray detectors, enabling X‐ray imaging and dosimetry in less accessible situations. However, it is a challenge to develop phosphor‐based detectors with high memory stability and convenient readout processes. Here, an approach to realize this using radiation‐induced photoluminescence tuning in (Ba1‐xSrx)2SiO4:Eu phosphors is demonstrated, ascribed to the reduction of Eu3+ toward Eu2+. The associated photoluminescence spectral change and the accompanying color contrast in response to the radiation dose are exploited for simultaneous X‐ray dosimetry and imaging. The recorded image can be read out conveniently by a regular photo camera upon UV illumination and the radiation dose can be extracted during the imaging process in a ratiometric way via the green to red pixel intensity, avoiding the need for absolute intensity measurement. Moreover, the imaged information can be maintained for longer than 28 days and the plate can 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 (Ba1‐xSrx)2SiO4:Eu for X‐ray‐based microbeam radiation therapy and nondestructive inspection and are expected to stimulate research on phosphor‐based photoluminescence modulated detectors.

Recent Progress and Trends in X-ray-Induced Photodynamic Therapy with Low Radiation Doses

“…Holloway et al reported that the radioluminescence intensity of Y 2 O 2 S:Eu 3+ decreased under ionizing radiation because of the low-efficiency Y 2 O 3 :Eu 3+ “dead layer” grown on the surface . Poelman et al found that (Ba 1– x Sr x ) 2 SiO 4 :Eu scintillators induced a new luminescence center through the valence change of Eu 2+ toward Eu 3+ under X-ray irradiation . Such radiation-induced luminescence tuning phenomenon may lead to a decrease in FRET efficiency between the scintillator and the photosensitizer, which results in a decrease in ROS production.…”

“…78 The decrease in a material's luminescence performance may also be due to induced absorption of the color center caused by radiation and radiation defects. 67 79 Such radiation-induced luminescence tuning phenomenon may lead to a decrease in FRET efficiency between the scintillator and the photosensitizer, which results in a decrease in ROS production. Fortunately, high-temperature sintering or hot-injection methods enabled the high crystalline nature of nanoscintillators to avoid possible defects or decomposition.…”

A Versatile Photochromic Dosimeter Enabling Detection of X‐Ray, Ultraviolet, and Visible Photons

“…[27][28][29][30] The well-developed passive dosimeters mainly include luminescent materials and photochromic materials. [11,17,29,[31][32][33][34][35][36][37] Luminescent materials operating on the principles of thermoluminescence (LiF:Mg,Ti and CaF 2 :Dy), optically stimulated luminescence (Al 2 O 3 :C and BeO, e.g. ), and radio-photoluminescence (Ag-doped phosphate glass and Al 2 O 3 :C,Mg, e.g.…”

Metal Halides Based Flexible X‐Ray Detectors

“…The development of X-ray detection has caused a high research boom due to its broad application prospects in non-destructive detection and medical diagnosis. [1][2][3][4] In recent years, X-ray detectors based on semiconductors like CdTe, 𝛼-Se, Si, and CsI:Tl have experienced rather rapid development, culminating in the application of planar detection. [5,6] However, with the rapid development of wearable devices and the diversification of detected object shapes, it is urgent to develop flexible X-ray detectors.…”