Patent Number: 061756156
Section: claims

1. A collimation apparatus comprising: a block of radiation-absorbing material having a front face and a rear face, a thickness of a said slab being defined as a distance between said front face and said rear face; and  a plurality of channels formed within and extending through said slab, each of said plurality of channels having an entrance opening and an exit opening, said plurality of channels being separated by and defined by a plurality of channel walls collectively comprising a web of said radiation absorbing material, said web comprising the portion of said slab material remaining after said plurality of channels are formed in said slab;  wherein each of said plurality of channels has a central longitudinal axis, and wherein said longitudinal axes of said plurality of channels intersect at a point located at a predetermined distance from said front face of said slab. 2. A collimation apparatus as recited in claim 1 wherein said slab of radiation absorbing material comprises material selected from the group consisting of tungsten, lead, and natural uranium. 3. A collimation apparatus as recited in claim 1 wherein each of said plurality of channels comprises a plurality of walls, and wherein each of said walls is tapered such that said walls converge to said point where said longitudinal axes of said channels intersect.