Abstract:

The technical theory of digital radiography mainly includes three aspects: the image quality representation, the theory of detail recognition, and the control theory of testing technology. In recent years, the testing image quality parameters are concerned by foreign correlative research. In China, the testing image quality parameters are fully discussed, the theory of detail recognition is systematically given from the visual characteristic law, and the technology of image digital control is introduced into the control theory of testing technology. Equivalence assessment is a question that needs to be solved and answered, when the film radiography technology is replaced by digital radiographic testing. In foreign countries, the comparison test is carried out. In China, the theory of imaging process is introduced, and a simple method is given to deal with the problem of technical standard and system equivalence.

Key words: defect testing, detail recognition, equivalence, testing image, digital radiography