4 results about "Gadolinium oxysulfide" patented technology

The invention relates to the technical field of scintillation screens, in particular to a scintillation screen based on gadolinium gallium aluminum garnet scintillation single crystals and a preparation method of the scintillation screen. The scintillation screen comprises a substrate, a light reflecting layer, a gadolinium gallium aluminum garnet scintillator powder screen and a light emitting layer, an inner groove is formed in the upper surface of the reflective layer, and the gadolinium gallium aluminum garnet scintillator powder screen is arranged in the inner groove; the gadolinium-gallium-aluminum garnet scintillator powder screen is prepared by mixing gadolinium-gallium-aluminum garnet scintillation single crystal particles and an inorganic binder in proportion, sintering and then grinding and polishing. The problems that an existing needle-shaped cesium iodide scintillation screen is not resistant to irradiation, prone to deliquescence and poor in afterglow, a gadolinium oxysulfide ceramic scintillation screen is poor in resolution ratio and low in luminous efficiency, and a Ce: GAGG single crystal spliced scintillation screen has a dead zone are solved, the irradiation stability and environmental adaptability of the scintillation screen are remarkably improved, the service life of the scintillation screen is remarkably prolonged, meanwhile, the preparation process is flexible, and the cost is low. And high-performance scintillation screens with different shapes and sizes can be prepared.

A scintillator screen for use in backscatter and transmission X-ray detectors is provided. The scintillator screen includes at least a phosphor layer comprising a plurality of phosphor particles preferably having a mean particle size ranging from 30 μm to 70 μm, and preferably from 30 μm to 50 μm. Alternatively, each of the plurality of phosphor particles has a particle size in a range of 30 μm to 70 μm, and preferably from 30 μm to 50 μm. A thickness of the scintillator layer ranges from 100 μm to 4000 μm while packing fraction of phosphor weight to total weight of phosphor and a binder ranges from 50% to 90%. The phosphor layer preferably includes europium-doped barium fluorochloride (BaFCl:Eu) for use in a backscatter X-ray detector and preferably includes Gadolinium Oxysulfide (Gd2O2S) for use in a transmission X-ray detector.

This invention relates to a method for fabricating a gadolinium oxysulfate X-ray scintillation screen based on a silicon microchannel array, as well as the X-ray scintillation screen and its applications, belonging to the field of X-ray imaging technology. It primarily addresses the technical problem of low resolution in existing X-ray scintillation screens. This invention fabricates a tetragonal silicon microchannel structure through photolithography, photoelectrochemical etching, and back-side thinning processes, fundamentally avoiding the problem of microchannel misalignment. The use of ALD tungsten film deposition and pulse electroplating for silver film deposition effectively reduces X-ray crosstalk. Furthermore, the good chemical compatibility between tungsten and silver ensures uniform silver film deposition without microchannel blockage, and the silver film possesses high reflectivity. Vacuum infusion is used to completely fill the microchannels with fluorescent material, avoiding the presence of air or other substances with significantly different refractive indices from the fluorescent material within the channels, and also solving the scattering and reflection problems caused by gaps between particles, effectively improving detection efficiency.

The application relates to a preparation method of a terbium-doped gadolinium oxysulfide fluorescent material, and the material performance is remarkably improved through an optimized high-temperature solid-phase method. The process is characterized in that: firstly, polyvinylpyrrolidone (PVP) and dopamine hydrochloride are used as dispersants and coating agents to prepare Gd2O3 and Tb4O7 oxide precursors which are uniformly dispersed; then, a fluxing agent system of boric acid and lithium carbonate is used in cooperation, and a three-stage sintering process of "low-temperature pre-sintering-middle-temperature sulfuration-high-temperature crystallization" is combined to effectively inhibit grain agglomeration and abnormal growth; finally, carbon impurities are removed through air annealing to obtain superfine fluorescent powder with small particle size and narrow distribution. Experiments show that the fluorescent powder in the examples has a particle size D50 of 496-678 nm, a fluorescent decay lifetime of more than 1100 mu s, high luminous intensity and excellent stability, and has a wide application prospect in the fields of liquid crystal display, biomedicine and the like.