According to one embodiment, an X-ray diagnostic apparatus includes an X-ray tube, an X-ray detection unit, an X-ray filter, an input unit, and an X-ray filter support unit. The X-ray tube generates X-rays. The X-ray detection unit detects the X-rays transmitted through a subject. The X-ray filter is arranged between the X-ray tube and the object and has an opening. The X-ray filter support unit supports the X-ray filter so as to make the X-ray filter movable in an imaging axis direction of the X-rays.

A sharpening filter for orthovoltage x-ray beams employs a substantially planar filter disk supporting a set of radial symmetric features controlling attenuation of x-ray transmission in concentric circular regions providing increased sharpness of the pencil beams in a compact filter structure that may be tailored to different beam sizes and focus depths.

An improved dual energy CT imaging system for providing improved imaging and improved material identification.

An X-ray filter assembly is disclosed having a stack of X-ray attenuating sheets that are angled so as to have a focus point. When implemented in an imaging system, the focus point of the filter assembly is spatially offset (e.g., behind) the X-ray emission location. The filter assembly may be used (e.g., translated, rotated, and so forth) to adjust the intensity profile of the X-rays seen in an imaging volume.

A filter assembly for use in a helical computed tomography system having an x-ray source for projecting x-ray beams along a projection axis is presented, the filter assembly including a first filter element for attenuating at least a portion of the x-ray beams, the first filter element constructed as a background-wedge for attenuating x-rays having a large aperture and a second filter element for attenuating at least a portion of the x-ray beams, the second filter element constructed to create a ridge. The second filter element may be rotated with respect to or adjusted in relation with or removed or replaced from the filter assembly to allow for adaptation to different helical pitch values.