Compact X-ray collimator

A beam limiting device comprising:

• two orthogonal pairs of opposing shutter elements disposed for defining a beam collimating aperture having an axial centerline, each of said elements having cylindrically curved wall portions disposed orthogonally to said axial centerline and longitudinal edge portions disposed for defining respective peripheral portions of said aperture;
• and
• means disposed adjacent at least one arcuate end of each of said cylindrically curved wall portions for rotating each of said shutter elements about its longitudinal axis and moving said longitudinal edge portions relative to one another for adjusting the size of the aperture.

A beam limiting device comprising:

• two orthogonal pairs of opposing cylindrically curved shutter elements disposed for defining a rectangular aperture, the elements of each of said pairs having respective longitudinal edge portions disposed in opposing relationship with one another between said cylindrically curved elements of the other pair and supported in spaced encircling relationship with respective arcuate ends thereof;
• and
• means disposed adjacent at least one arcuate end of each of the elements of said pairs for rotating said each of the elements in respective opposing directions about its longitudinal centerline and adjusting the size of said aperture.

A radiation collimator comprising:

• (a) a housing;
• (b) a first and a second pair of shutter elements disposed within the housing, the first pair of shutter elements being rotatably mounted with respect to the housing about a first pair of parallel axes and the second pair of shutter elements being rotatably mounted with respect to the housing about a second pair of parallel axes, the first pair of parallel axis being perpendicular to the second pair of parallel axes, each one of such shutter elements having a concave surface with a pair of edge portions thereof parallel to the axis of rotation of such shutter element, one of such edge portions thereof defining a different peripheral portion of an aperture, one of the pair of edge portions of the surfaces of the first pair of shutter elements being adapted to rotate within a space disposed between the surfaces of the second pair of shutter elements and one of the pair of edge portions of the surfaces of the second pair of shutter elements being adapted to rotate within a space disposed between the surfaces of the first pair of shutter elements.