Patent ID: 7804933

Claim:
A dental computer tomography apparatus, which includes: an arm structure connected to a body part ( 10 ) of the apparatus ( 1 ) or to a fixed structure not belonging to the actual apparatus ( 1 ), which arm structure includes an arm part ( 13 ) comprising imaging means ( 14 , 15 ) and which is turnable around a centre of rotation ( 23 ), which said imaging means comprise a radiation source ( 14 ) and an imaging detector ( 15 ), which are located essentially at the opposite ends of said arm part ( 13 ), a collimator structure for limiting radiation produced by the said radiation source ( 14 ) to a beam, patient support means ( 16 ) in connection with an imaging station arranged in connection with the apparatus, and a control system ( 31 ) for controlling and realizing operation and movements of said radiation source ( 14 ) and imaging detector ( 15 ), as well as for controlling and realizing movements of said arm structure, wherein said arm part ( 13 ) comprising the imaging means ( 14 , 15 ) is connected to said body part ( 10 ) of the apparatus, or to some other structure of the apparatus which is fixed with respect to the patient support means ( 16 ), via at least two other turnable arm parts ( 11 , 12 ), which each of the at least two arm parts ( 11 , 12 ) is arranged to be turnable with respect to at least two centres of rotation ( 21 , 22 , 23 ) locating at a distance from each other substantially on the same plane, out of which centres of rotation ( 21 , 22 , 23 ), the outmost centres of rotation ( 21 , 23 ) of the outmost arm parts ( 11 , 12 ) of said at least two arm parts connect, on the one hand, to said arm part ( 13 ) comprising imaging means and, on the other hand, to said body part ( 10 ) or other structure which is fixed with respect to the patient support means ( 16 ).