Abstract: A radionuclide scanner in which multiple detectors are equipped with collimators such that a circular rotation of the detector around a target provides the movement needed for collimator sampling. This collimator sampling is accomplished through strategic placement of the detector heads relative to each other such that for any given projection, a complete imaging of the projection is acquired by summing the complementary contributions of the multiple detector heads at the projection under consideration.

Abstract: A radionuclide scanner in which multiple detectors are equipped with collimators such that a circular rotation of the detector around a target provides the movement needed for collimator sampling. This collimator sampling is accomplished through strategic placement of the detector heads relative to each other such that for any given projection, a complete imaging of the projection is acquired by summing the complementary contributions of the multiple detector heads at the projection under consideration.

Abstract: A fail-safe ball screw assembly has a double-start screw and a corresponding nut. The screw has a first helix with a truncated, smaller diameter flat and an intertwined second helix with an extended, larger diameter flat. Similarly, the corresponding nut has a first helix with an extended, larger diameter flat and an intertwined second helix with a truncated, smaller diameter flat. When the screw is inserted with the nut, the screw's truncated first helix is paired with the nut's extended first helix, and the screw's extended second helix is paired with the nut's truncated second helix. The nut and screw helixes combine to form channels in which bearings balls travel. The bearings allow the fail-safe ball screw assembly to operate with high efficiency and precision, while the overlapping structure of the helixes prevents catastrophic failure caused by the removal or loss of the bearing balls.

Abstract: A high voltage distribution system for distributing a high voltage supply to a plurality of semiconductor radiation detector modules, includes a conductive strip connected to a high voltage supply. The conductive strip is preferably made of aluminum foil, and contacts a surface of each of the detectors. The conductive strip is held into contact with the semiconductor radiation detectors by applying pressure to said conductive strip with a pressure plate, including a compressible layer such as a foam layer. A vacuum is created in an area occupied by the semiconductor modules and the conductive strip. The high voltage distribution system allows a high negative voltage to be applied to the semiconductor detector modules with a minimum of attenuation. In a preferred embodiment, the detector modules are CZT modules, and the system is incorporated into a solid-state gamma camera for nuclear medicine imaging.