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Abstract

Equipment for automatic adjustment of image receptor exposure during imaging in panoramic or tomographic radiography. The equipment includes: a radiation source (4) and an image receptor (7), the radiation (5) passing through the object (6) to be X-ray examined, placed between these; at least two interspaced detectors (1), placed behind the image receptor and measuring the radiation intensity; memory means for storing exposure reference values; and adjustment means (3), which adjust variables affecting the image receptor exposure during X-raying on the basis of signals from the detectors and reference values. The apparatus also includes an integrator for each separate detector (1a, 1b, 1c, . . . ) or detector array, connected directly to the detector outputs, whereby a measurement channel starts from each detector or detector array and the integration intervals of the integrators have been set to be shorter than the overall imaging period; at least one memory unit in the memory means for each measurement channel for storing a plurality of predetermined exposure values; and a calculating unit (23) which compares each integral obtained from the different channels with an exposure value prestored in the memory unit of the corresponding channel and produces a combined effect result of the comparison results, which is fed in the adjustment means (3).

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First Claim