Quality Evaluation for the Digital Radiography Inspection Based on Imaging Parameters

摘要

The systme properties and qualities should be nleasured periodically to ensure the good condition of the digital radiography imaging system The parameters of mlsharpness,contrast and sgnal to noise ratio were defined and measured in this paper.Based on these parameters,an evaluationg for the system could be achieved for the digital radiography inspectiong By means of measuring the mlsharpness using modulation transfoilllation fimction(MTF) method and duplex method,the basic spatial resolution could be detemfined. Contrast properlies were described by the contrast sensitivity and the wall thickness range The signal to noise ratio was characterized by the measurement of mean and standard deviation value on different regions of interesting. The Image Quahty Indicator(IQI)was used to control the imaging qualities. Under its incorporating with three imaging paranleters,the inspection system could be check for its rehability and stable perfoi]ilance. Also it could provide a guidance to check and accept a new system.