Patent ID: 7660381

Claim:
An X-ray imaging system comprising a) an X-ray source for generating a primary X-ray beam, b) an image detector for detecting, and generating an electrical signal representative of, radiation transmitted through a subject to be imaged located between said X-ray source and said image detector c) collimator means provided between said X-ray source and said subject to be imaged for collimating said primary X-ray beam, said image detector having a defined active area and said collimator means being arranged and configured to collimate said primary X-ray beam such that said radiation transmitted through said subject is incident on a portion of said active area of said image detector, and d) means for determining a scatter level from a signal generated in respect of a portion of said active area of said image detector outside of the area thereof on which said transmitted radiation is incident, wherein the portion of the active area for which the scatter level is determined borders the entire area on which the transmitted radiation is incident.