Abstract: A radiation detector device is disclosed that includes a scintillator including a scintillator crystal and a hybrid photodetector (HPD) coupled to the scintillator. The HPD includes an electron tube having an input window and a photocathode adapted to emit photoelectrons when light passing through the input window strikes the photocathode. Further, the hybrid photodetector includes an electron detector adapted to receive photoelectrons emitted by the photocathode. The electron detector comprises a semiconductor material characterized by a bandgap of at least 2.15 eV.

Abstract: A radiation detector device is disclosed that includes a scintillator including a scintillator crystal and a hybrid photodetector (HPD) coupled to the scintillator. The HPD includes an electron tube having an input window and a photocathode adapted to emit photoelectrons when light passing through the input window strikes the photocathode. Further, the hybrid photodetector includes an electron detector adapted to receive photoelectrons emitted by the photocathode. The electron detector comprises a semiconductor material characterized by a bandgap of at least 2.15 eV.

Abstract: A scintillation detector apparatus comprising a filter disposed intermediate a scintillator and a detector, the filter being adapted to block relatively long wavelengths of light to reduce afterglow. The detector apparatus may, for example, be a part of a detector system such as a CT scanner, a RG system, or a geophysical measurement system.

Abstract: A radiation detector, in particular a gamma camera, is constructed and operated in such a fashion that only a predetermined number of light sensors (such as PMT's) adjoining each other in a cluster are used to generate a signal with amplitude and event position information. The camera may also use an array of individual scintillation elements (crystals) in place of a single crystal, with certain advantages obtained thereby. According to another aspect of the invention, there is a reflector sheet that defines an array of apertures through which scintillation light can pass from the scintillation crystal to a plurality of light sensors optically coupled to an optical window in an array corresponding to the array of apertures in the reflector.

Abstract: A gamma camera plate incorporates scintillation crystal which is sufficiently thick to effectively capture high energy radiation. The crystal is provided on its light output side with an array of light path-modifying partitions which extend partly through its thickness. These partitions define individual light collimating cells which reduce the light spreading which would otherwise prevent effective use of the plate for low energy radiation.

Abstract: A gamma camera plate incorporates scintillation crystal which is sufficiently thick to effectively capture high energy radiation. The crystal is provided on its light output side with an array of light path-modifying partitions which extend partly through its thickness. These partitions define individual light collimating cells which reduce the light spreading which would otherwise prevent effective use of the plate for low energy radiation.

Abstract: A gamma camera plate incorporates scintillation crystal which is sufficiently thick to effectively capture high energy radiation. The crystal is provided on its light output side with an array of light path-modifying partitions which extend partly through its thickness. These partitions define individual light collimating cells which reduce the light spreading which would otherwise prevent effective use of the plate for low energy radiation.

Abstract: A gamma camera scintillation crystal plate assembly and method that may be used for both PET (positron emission tomography) and SPECT (single photon emission computer tomography). The crystal plate assembly includes two or more crystals which are optically coupled and tuned so as to control the energy position of the photopeaks at an output surface of the plate assembly. The crystals are tuned by various means including varying the surface finishes and material selection.

Abstract: A radiation detector, in particular a gamma camera, is constructed and operated in such a fashion that only a predetermined number of light sensors (such as PMT's) adjoining each other in a cluster are used to generate a signal with amplitude and event position information. The camera may also use an array of individual scintillation elements (crystals) in place of a single crystal, with certain advantages obtained thereby. According to another aspect of the invention, there is a reflector sheet that defines an array of apertures through which scintillation light can pass from the scintillation crystal to a plurality of light sensors optically coupled to an optical window in an array corresponding to the array of apertures in the reflector.

Abstract: A compact medical nuclear imaging device, which generates a medical image from gamma radiation, can be held stationary or moved to search a large area for locating a radioactive area of interest. The compact medical imaging device comprises a collimator having an array of collimating channels, a radiation collection module converting the gamma radiation to an electric signal, an electronic module for processing the electrical signal, and a display module for displaying a two-dimensional image of the radiation scene, all of which preferably are assembled together in a single, compact module of a size small enough to permit it to be held and maneuvered by a human operator.

Abstract: A scintillation detector having reduced temperature sensitivity is provided by having two circuits for temperature compensation. The two circuits may be a thermistor in parallel with both a resistive element and a switching element. The switching element can be various devices including a zener diode, a Schottky barrier diode or an MIM. The temperature compensation circuit may be included in the circuit of a photo-detector such as a photomultiplier tube.