Patent ID: 6715918
Filing Date: 2004-04-06
Classification: A61B,G01N

Abstract:
A calibration phantom (20) for determining at least one projection geometry of X-ray apparatuses which are designed for recording radiographic projection images of objects for a representation of the objects which is derived from this with the aid of a reconstructive imaging method, the calibration phantom comprising a support (22) in the form of a defined volume body or hollow body and markings (15, 24, 25), which are applied in a linear arrangement (23) to the surface and/or within the support (22),the markings (15, 24, 25) having a first X-ray absorption capability and the support (22) having a second X-ray absorption capability, which is different from the first X-ray absorption capability, the linear arrangement (23) of the markings (15, 24, 25) precluding superimposition of an image of a first marking with an image of a second marking for a sufficient number of successive markings for each projection condition, the physical embodiment of a marking (15, 24, 25) representing a value assignment, and the value assignments for a sequence of successive markings (15, 24, 25) forming code information, wherein a first number of successive markings (15, 24, 25) form a first type of code information, with each code information item of the first type occurring once, and only once, in both sequence directions of the markings (15, 24, 25), and thus being unique.