Abstract: A phoswich device for determining depth of interaction (DOI) includes a first scintillator having a first scintillation decay time characteristic, a second scintillator having a second scintillation decay time characteristic substantially equal to the first scintillation decay time, a photodetector coupled to the second scintillator, and a wavelength shifting layer coupled between the first scintillator and the second scintillator, wherein the wavelength shifting layer modifies the first scintillation decay time characteristic of the first scintillator to enable the photodetector to differentiate between the first decay time characteristic and the second decay time characteristic. The phoswich device is particularly applicable to positron emission tomography (PET) applications.

Abstract: A phoswich device for determining depth of interaction (DOI) includes a wavelength shifting layer between first and second scintillators of different scintillation materials and having different decay time characteristics. The wavelength shifting layer allows a true phoswich device to be constructed where the emission wavelength of one scintillator is in the peak excitation band of the other scintillator, by shifting the scintillation light outside of this excitation band to prevent scintillation light of one scintillator from exciting a response in the other scintillator, thus enabling unique identification of the location of a gamma photon scintillation event. The phoswich device is particularly applicable to positron emission tomography (PET) applications.

Abstract: A phoswich device for determining depth of interaction (DOI) includes a first scintillator having a first scintillation decay time characteristic, a second scintillator having a second scintillation decay time characteristic substantially equal to the first scintillation decay time, a photodetector coupled to the second scintillator, and a wavelength shifting layer coupled between the first scintillator and the second scintillator, wherein the wavelength shifting layer modifies the first scintillation decay time characteristic of the first scintillator to enable the photodetector to differentiate between the first decay time characteristic and the second decay time characteristic. The phoswich device is particularly applicable to positron emission tomography (PET) applications.

Abstract: Crystals with improved scintillation and optical properties are achieved by codoping with a trivalent dopant and a divalent and/or a monovalent dopant. Embodiments include codoping LSO, YSO, GSO crystals and LYSO, LGSO, and LYGSO crystals. Embodiments also include codoped crystals with a controlled monovalent or divalent:trivalent dopant ratio of from about 1:1 for increased light yield to about 4:1 for faster decay time.

Abstract: A phoswich device for determining depth of interaction (DOI) includes a wavelength shifting layer between first and second scintillators of different scintillation materials and having different decay time characteristics. The wavelength shifting layer allows a true phoswich device to be constructed where the emission wavelength of one scintillator is in the peak excitation band of the other scintillator, by shifting the scintillation light outside of this excitation band to prevent scintillation light of one scintillator from exciting a response in the other scintillator, thus enabling unique identification of the location of a gamma photon scintillation event. The phoswich device is particularly applicable to positron emission tomography (PET) applications.

Abstract: A detector array including a plurality of scintillators for use in association with an imaging device. The detector array is provided for accurate determination of the location of the impingement of radiation upon an individual scintillator detector. An air gap is disposed between the scintillator elements, thereby increasing the packing fraction and overall sensitivity of the array. The amount of light transmitted down the scintillator element and the amount of light transmitted to adjacent elements is modified to optimize the identification of each element in a position profile map by adjusting the surface finish of the detector elements.

Abstract: Apparatus and method for providing nuclear medical imaging, in particular positron emission tomography, wherein a panel detector including scintillation blocks with a light guide is attached thereto. The scintillation block is arranged to cover a plurality of photosensors in an N by N configuration where there are outer photosensors which share light information from adjacent scintillation blocks and at least one center photosensor which does not share light information from adjacent scintillation blocks.

Abstract: A detector for use in imaging applications includes at least one detector array, an array of photodetectors, and a continuous light guide disposed between the detectors and the photodetectors. The light guide is continuous over the entire area of the photodetectors and detectors. The thickness of the light guide is optimized based on the shape of the photodetector array. Each detector array includes a plurality of scintillator elements disposed in an M×N array, where “M” and “N” are independently selectable and are each at least one. A mechanism for maintaining the relative positions of the individual scintillator elements with respect to each other is provided. The retainer is further provided to enhance the separation between the individual detector arrays to define distinct boundaries between the position profiles of the scintillator arrays.

Abstract: A detector array including a plurality of scintillators for use in association with an imaging device. The detector array is provided for accurate determination of the location of the impingement of radiation upon an individual scintillator detector. An air gap is disposed between the scintillator elements, thereby increasing the packing fraction and overall sensitivity of the array. The amount of light transmitted down the scintillator element and the amount of light transmitted to adjacent elements is modified to optimize the identification of each element in a position profile map by adjusting the surface finish of the detector elements.

Abstract: A grid array adapted to receive a plurality of scintillators for use in association with an imaging device. The grid array is highly reflective such that location of the impingement of radiation upon an individual scintillator detector is accurately determinable. The grid array allows an air gap between each scintillator and the reflector material, as well as provides a highly reflective medium that produces sufficient light output while controlling cross-talk between the discrete scintillator elements. The grid array defines an M×N array of scintillator element cells. The grid array is manufactured using a conventional method such as injection molding. The grid array is fabricated from a highly reflective material. The scintillator elements are each cut to size and then inserted such that a uniform, flat surface to be achieved. In one embodiment, a bottom wall is be defined by each of the scintillator element cells.

Abstract: The carbon content in iron, cobalt, or nickel based alloys containing at least about 16% chromium is substantially eliminated without significant loss of chromium by blowing the alloy with oxygen to oxidize the carbon and simultaneously introducing steam or ammonia in amounts such that the partial pressure of carbon monoxide (formed by oxidation of carbon) is lower than that which corresponds to the equilibrium pressure for the carbon/chromium oxidation e.g. below 0.95 and preferably below 0.5 atmospheres.