【摘 要】
:
We design a novel X-ray image detector by lens coupling a Gd2O2S:Tb intensifying screen with a high performance low-light-level (L3, which often means luminescence less than 10^(-3) Lux) image intensifier. Different coupling effects on imaging performance
【机 构】
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KeyLaboratoryofIntegratedMicrosystems,ShenzhenGraduateSchoolofPekingUniversity,Shenzhen518055Schoolo
【出 处】
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ChineseOpticsLetters
论文部分内容阅读
We design a novel X-ray image detector by lens coupling a Gd2O2S:Tb intensifying screen with a high performance low-light-level (L3, which often means luminescence less than 10^(-3) Lux) image intensifier. Different coupling effects on imaging performance between zoom lens and fix-focus lens are analyzed theoretically. In experiment, for designing a detector of 15-inch visual field, the system coupled by zoom lens is of 12.25-lp/cm resolution, while the one with fix-focus lens is 10 lp/cm. The superiority of zoom lens is validated. It is concluded that zoom lens preserves the image information better than fix-focus lens and improves the imaging system’s performance in this design, which is referential to the design of other optical imaging systems.
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