Patent ID: 6510196
Filing Date: 2003-01-21
Classification: A61B,H05G

Abstract:
A device for determining exposure values in an X-ray panoramic and/or cephalometric apparatus (20, resp. 21) for imaging patient's head (3) or a part thereof, which apparatus comprises an X-ray tube (22), an exposure control means (10) providing a tube voltage, a tube current and an exposure time, and adjustable support means (11) for a patient's head, said support means being provided with at least two support elements (1a, 1b) with a variable spacing (W1) therebetween on the opposite sides of the patient's head, and said support means being adapted for positioning against the patient's head prior to an exposure, characterized in that said device comprises:a sensor (2) connected to said two support elements and providing an electrical output proportional to the spacing (W1) of said support elements (1a, 1b) and accordingly proportional to dimension (W2) of the patient's head therebetween; and a control unit (4) or a connection (5) feeding said electrical output (S) transformed or non-transformed to the exposure control means (10), so adjusting the current (It) and/or the voltage (Ut) of the X-ray tube and/or the exposure time (T) to be at one of a plurality of predetermined levels, each of which being in a predetermined relationship with the spacing (W1) of said support elements.