Modulation transfer function of a digital dental x-ray system.
An impulse train method to control aliasing was used to measure the modulation transfer function of a digital dental x-ray system (RVG 32000 ZHR, Trophy Radiologie, Vincennes, France). The detector of this system is composed of an intensifying screen, a fiber optics taper, and a charged couple device chip. The modulation transfer function could not be measured by impulse method such as the line spread function or edge response function because of aliasing from undersampling of the digital system. The system modulation transfer function was difficult to recover at the spatial frequencies smaller than the Nyquist frequency. The modulation transfer function beyond the Nyquist frequencies was impossible to recover in this study.
Chen
S K
SK
Department of Oral Medicine, School of Dentistry, University of Washington, Seattle.
Hollender
L
L
D005583:Fourier Analysis; D008961:Models, Structural; D055095:Optics and Photonics; D017785:Photons; D011856:Radiographic Image Enhancement / Q000295:instrumentation*; D011858:Radiographic Magnification; D011861:Radiography, Dental / Q000295:instrumentation* / Q000379:methods / Q000592:standards; D012666:Semiconductors; D012815:Signal Processing, Computer-Assisted; D014741:Video Recording; D014963:X-Ray Intensifying Screens