Prediction of Perceptibility Curves of direct digital intraoral radiographic systems

Objectives: To derive and test a method to predict Perceptibility Curves (P Cs) for direct digital intraoral radiographic systems. Methods: A test object was used to determine the performance of an average observer with respect to the threshold contrast and internal noise of the h uman visual system. These data were combined with system parameters to pred ict PCs mathematically. Results: Data on the performance of an average observer could be defined to obtain values of the effective threshold contrast as a function of backgro und gray level. This function combined with the gamma-value of the system p redicted PCs that agreed well with PCs obtained in the conventional way. Conclusion: It is possible to predict PCs from a limited number of system p arameters together with predetermined data on an average observer.