Radiation detector employing solid-state scintillator material and preparation methods therefor
First Claim
1. A radiation detector for a computerized tomography scanner exhibiting improved afterglow characteristics when used with a source of penetrating x-ray radiation, said radiation detector comprising:
- a detector array housing;
a plurality of channels defined in said housing, for receiving said radiation;
a polycrystalline ceramic scintillator body disposed in each said channel so that x-ray radiation being received by said channel is incident on said scintillator body, and so that said incident radiation causes said body to scintillate at a wavelength, the composition of said scintillator body consisting essentially of between about 5 and 50 mole percent Gd2 O3, between about 0.02 and 12 mole percent of a rare earth activator oxide selected from the group consisting of Eu2 O3 and Nd2 O3, and between about 0.008 and 0.5 mole percent of at least one afterglow reducer selected from the group consisting of Pr2 O3 and Tb2 O3, the remainder of said composition being Y2 O3 ; and
means for detecting said wavelength scintillator energy emitted from each said scintillator body and for generating electrical signals in response thereto, said detecting means being coupled to each said scintillator body so as to produce a set of signals related to the x-ray radiation received in the respective channels of said detector array housing.
0 Assignments
0 Petitions
Accused Products
Abstract
A polycrystalline ceramic scintillator exhibiting reduced afterglow includes between about 5 and 50 mole percent Gd2 O3, between about 0.02 and 12 mole percent of either Eu2 O3 or Nd2 O3 as a rare earth activator oxide, and between about 0.003 and 0.5 mole percent of either Pr2 O3 and Tb2 O3 as an afterglow reducer. The remainder of the scintillator composition is Y2 O3. The resulting scintillator is especially useful for a radiation detector of the type having a plurality of radiation receiving channels. A scintillator body is disposed in each channel so that radiation being received therein is incident on the scintillator body and causes the body to convert the incident radiation to light energy of a predetermined wavelength. The radiation detector also includes means for converting the light energy from the scintillator into electrical signals which are proportional to the amount of radiation incident on the scintillator body. Methods for preparing the scintillator of the present invention include sintering, sintering combined with gas hot isostatic pressing, and vacuum hot pressing.
-
Citations
21 Claims
-
1. A radiation detector for a computerized tomography scanner exhibiting improved afterglow characteristics when used with a source of penetrating x-ray radiation, said radiation detector comprising:
-
a detector array housing; a plurality of channels defined in said housing, for receiving said radiation; a polycrystalline ceramic scintillator body disposed in each said channel so that x-ray radiation being received by said channel is incident on said scintillator body, and so that said incident radiation causes said body to scintillate at a wavelength, the composition of said scintillator body consisting essentially of between about 5 and 50 mole percent Gd2 O3, between about 0.02 and 12 mole percent of a rare earth activator oxide selected from the group consisting of Eu2 O3 and Nd2 O3, and between about 0.008 and 0.5 mole percent of at least one afterglow reducer selected from the group consisting of Pr2 O3 and Tb2 O3, the remainder of said composition being Y2 O3 ; and means for detecting said wavelength scintillator energy emitted from each said scintillator body and for generating electrical signals in response thereto, said detecting means being coupled to each said scintillator body so as to produce a set of signals related to the x-ray radiation received in the respective channels of said detector array housing. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
- 9. A polycrystalline ceramic scintillator exhibiting improved afterglow characteristics, said scintillator comprising a composition consisting essentially of between about 5 and 50 mole percent Gd2 O3, between about 0.02 and 12 mole percent of a rare earth activator oxide selected from the group consisting of Eu2 O3 and Nd2 O3, and between about 0.008 and 0.5 mole percent of at least one afterglow reducer selected from the group consisting of Pr2 O3 and Tb2 O3, the remainder of said composition being Y2 O3.
- 14. A polycrystalline ceramic scintillator exhibiting improved afterglow characteristics, said scintillator comprising a composition consisting essentially of between about 5 and 50 mole percent Gd2 O3, between about 0.02 and 12 mole percent of a rare earth activator oxide selected from the group consisting of E2 O3 and Nd2 O3, and between about 0.008 and 0.016 mole percent of at least one afterglow reducer selected from the group consisting of Pr2 O3 and Tb2 O3, the remainder of said composition being Y2 O3.
-
20. A radiation detector exhibiting improved afterglow characteristics when used with a source of penetrating radiation, said radiation detector comprising:
-
a detector array housing; a plurality of channels defined in said housing, for receiving said radiation; a polycrystalline ceramic scintillator body disposed in each said channel so that radiation being received by said channel is incident on said scintillator body, and so that said incident radiation causes said body to scintillate at a wavelength, the composition of said scintillator body consisting essentially of between about 5 and 50 mole percent Gd2 O3, between about 0.02 and 12 mole percent of a rare earth activator oxide selected from the group consisting of Eu2 O3 and Nd2 O3, and between about 0.008 and 0.5 mole percent of an afterglow reducer consisting of Pr2 O3, the remainder of said composition being Y2 O3 ; and means for detecting said wavelength scintillator energy emitted from each said scintillator body and for generating electrical signals in response thereto, said detecting means being coupled to each said scintillator body so as to produce a set of signals related to the radiation received in the respective channels of said detector array housing.
-
-
21. A polycrystalline ceramic scintillator exhibiting improved afterglow characteristics, said scintillator comprising a composition consisting essentially of between about 5 and 50 mole percent Gd2 O3, between about 0.02 and 12 mole percent of a rare earth activator oxide selected from the group consisting of Eu2 O3 and Nd2 O3, and between about 0.008 and 0.016 mole percent of an afterglow reducer consisting of Pr2 O3, the remainder of said composition being Y2 O3.
Specification