射線數字成像檢測技術

介紹多種射線數字成像(DR)系統的組成及成像機理，分析其性能指標、優缺點及應用領域。光子放大的DR 系統(如圖像增強器DR 系統)實時性好，但適應的射線能量低，檢測靈敏度相對較低；其它系統的檢測靈敏度較高但成像時間較長。DR 系統成像方式的主要區別在于射線探測器，除射線轉換方式外，影響系統檢測靈敏度的主要因素是散射噪聲和量子噪聲；可采用加準直器和光量子積分降噪的方法提高檢測靈敏度。

The structure and imaging principle of digital radiographic （DR） systems are introduced. And thecharacteristics, performances, advantages, disadvantages and applications of the
systems are analyzed. The DR sys-tern with photon amplification such as the DR system with
intensifier can get real-time imaging, but it fits for lowerenergy and its inspection sensitivity is lower.The systems working with high energy can obtain higher sensitivity,while is time-eonsurning. The imaging way of a DR system depends on the detector used, and the factors influencinginspection sensitivity are the quantum noise from ray source and scatter noise besides the transform way of rays.Quantum integration noise reducer and collimator can be used to improve the inspection sensitivity of the system.