Automatic exposure control for dental panoramic and cephalographic x-ray equipment

摘要

An apparatus and method used in dental panoramic and cephalographic x-ray equipment provides automatic adjustment of the pre-programmed exposure factors in order to obtain optimisation of the grey scale of the latent image on various kinds of x-ray detectors, such as the radiographic film or x-ray image detector plates. A sensor, such as photo diodes, detects the intensity of the radiation passed through the patient and incident on the x-ray detector and feeds it to a control unit. The control unit provides a computed simulation of the latent image grey level and adjusts the programmed exposure factors in order to establish the grey level of the latent image at the required reference value.