Determination and adjustment of exposure values for X-ray imaging

摘要

A device for determining exposure values in an X-ray panoramic and/or cephalometric apparatus (20) for imaging patient's head (3). The apparatus comprises adjustable support means (11) provided with support elements (1a, 1b) with a variable spacing (W1) therebetween, and said support means being adapted for positioning against the patient's head prior to exposure. A sensor (2) is connected to said support elements and it provides an electrical output proportional to the dimension (W2) of the patient's head therebetween. An exposure control means (10) adjust the tube current and/or the tube voltage of the X-ray tube and/or the exposure time to be at one of a plurality of predetermined levels.