Design and performance evaluation of different high-resolution scintillators in digital X-ray imaging detector

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 1063; p. 169323
• Main Authors: Cha, Bo Kyung, Jeon, Sungchae, Lee, Minjae, Lee, Hunwoo, Cho, Hyosung, Seo, Chang-Woo
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.06.2024
• Subjects: CMOS flat panel imager; Scintillation screens; X-ray imaging; Scintillation screens; X-ray imaging; CMOS flat panel imager
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/j.nima.2024.169323

In recent years, digital X-ray imaging detectors with indirect detection technology have been widely used in dental digital radiography such as intra-oral, panorama and dental CT. These indirect X-ray imaging detectors are based on the combination of a complementary metal-oxide semiconductor (CMOS) array with various high-resolution scintillating screens such as CsI, GOS materials. Currently, a CMOS panel-based indirect X-ray imaging detector with low radiation dose and excellent spatial resolution has been widely utilized for digital intra-oral radiography. In this work, different high-resolution scintillation screens such as FOS (fiber optic scintillator) with needle structured CsI:Tl and Gd2O2S:Tb(GOS) materials with different mass density(or screen thickness) were used to investigate and optimize the imaging characterization. The used different FOS screens are a highly X-ray absorption material that minimizes and removes the direct X-ray induced noise. The used scintillator's configuration parameters were tested and optimized for superior image quality at low X-ray exposure condition. For image characterization and optimization of the X-ray image device, different scintillating screens were directly combined on the bare high-resolution CMOS photodiode array. The imaging performance such as the relative light response to same X-ray exposure dose, modulation transfer function (MTF) and X-ray imaging with a tooth phantom was measured under practical dental condition with 60-65 kVp tube voltage and 10 mA tube current. The X-ray imaging with high spatial resolution could be implemented through the experimental results with a CMOS imaging detector using different FOS with CsI and GOS materials.