摘要
针对实际锥束CT系统成像质量退化的问题,提出一种基于多孔成像的方法测量并评估锥束CT系统的点扩展函数(point spread function,PSF)。首先针对平板探测器(flat panel detector,FPD)的PSF进行测量,设计了针孔测量装置,并据此提出一种简便的基于图像恢复的针孔成像PSF测量方法;然后分析了一般条件下锥束CT成像的PSF,提出面向切片图像恢复质量的多孔成像PSF测量与评估方法,并建立了任意直径针孔测量PSF的计算模型。实验结果验证了该方法的可行性,并得到了可恢复出较高质量切片图像的锥束CT系统PSF。
Aiming at the imaging quality degradation problem of the actual cone-beam CT, a method based on multipinhole imaging has been proposed to measure and evaluate the point spread function （PSF） of the cone-beam CT system. First of all, the PSF of the flat panel detector （FPD） is measured, and a pinhole measurement device is designed. Hereby, a simple method of pinhole imaging is put forward to measure the PSF based on image restoration.Then, the PSF of the cone-beam CT under general condition is analyzed ; the measurement and evaluation method of the PSF of multi-pinhole imaging is put forward based on the recovery quality of the slice image. A PSF calculation model is established for the pinholes with any diameters. Experiment results show the feasibility of this method, and the PSF cone-beam CT system is obtained, with which high quality image slices are restored.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2012年第9期2061-2066,共6页
Chinese Journal of Scientific Instrument
基金
国家自然科学基金(51105315)
国家科技重大专项(2012ZX04007021)
西北工业大学基础研究基金(JC20110253)资助项目
关键词
锥束CT
点扩展函数
平板探测器
小孔成像
图像恢复
cone beam CT
point spread function （PSF）
fiat panel detector （FPD）
pinhole imaging
image restoration
