目的 设计低微参数采集器用于CT机,实现CT机低微参数扫描高性能成像.方法采用多层固体探测器或硅光电池与碘化铯闪烁晶体等组成微光积分增强式探测器和高功率线性放大器,用于CT机,可使球管电流降为μA级,并加深聚焦罩的负电压和提高管电压.用20 cm厚的水模体定位曝光测试,将本文设计参数、影像质量与原CT机采集器的相应参数和影像质量相比较.结果用5~47μA(μGy级)、100 kV或140 kV曝光:原CT机采集器输出为5 mV~12 V、0.12~60 mA,稳定度与重复性为±0.089 V%,噪声电信号为0.083 nV、69 pA,一致性2.7%;而本文设计的采集器输出为5 mV~28 V或109 mA~1.67 A、噪声信号为0.033 nV、2.43 pA,稳定度与重复性为±0.014 V%,一致性＜2.1%,本文设计的采集器参数均优于传统CT机的采集器参数.结论本文设计的微参数采集器可使CT机实现球管μA级电流,低功耗、微剂量、超微焦点的低微参数扫描和高速度、高清晰、多功能的高性能成像.且小体积和低成本,有望成为CT机的新设计模式.%Objective To design a micro-parameter collector used in CT, to realize high-performance imaging by low micro-parameters scanning of CT. Methods Used multilayer solid detector or silicon photocell with a CSI scintillator crystal to make twilight integral enhancement type detector and high voltage, power linear amplifier, and the whole light enhancement collector of coupled transmission is used in CT collector. The tube current is reduced to micro-ampere level, the negative voltage focusing hood is deepened and tube voltage is improved. 20 cm water phantom is used in positioning and exposure test, to compare corresponding parameters and the image quality. Results Using 5-47 μA(μGy), 100 kV or 140 kV exposure: the original CT collector output is 5 mV～12 V, 0.12 mA～60 mA, stability and repeatability is about ± 0.089 V%, noise signal is 0.083 nV, 69 pA, consistency is 2.7%. But the collector output in this paper is 5 mV～28 V or 109 mA～l .67 A noise signal is 0.033 nV, 2.43 pA stability and repeatability is ± 0.014V%, actual consistency is less than 2.1%, collector parameters are all better than conventional CT. Conclusion Micro-parameter collector can make CT tube micro ampere-level current, low power, micro dose, low micro-parameter scanning of fine focus and high speed, high resolution, multi function of high-performance imaging, and the small size and low cost, which would be expected to become the new design pattern of CT.
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