Patent ID: 7046757

Claim:
An apparatus for eliminating noise caused by X-ray scatter contamination in a radiographic imaging device having an X-ray source for emitting a beam of X-ray radiation toward an object, a detector assembly for receiving at least part of the X-ray radiation after the X-ray radiation passes through the object and producing a signal in response thereto, the signal including a primary signal component and a noise component caused by X-ray scatter contamination, comprising: a grating disposed between the object and the detector assembly, the grating having an absorption that varies periodically for varying and amplitude modulating the intensity of the X-ray radiation passed through the grating and received by the detector assembly; a band-pass filter for filtering the noise component of the signal from the primary signal component, wherein the variation in intensity of the X-ray radiation passed through the grating causes a frequency shift of the primary signal component from the noise component of the signal for filtering the noise component of the signal from the primary signal component.