Ceramic scintillators based on the composition Gd2O2S: Pr: Ce have high efficiency in converting X- rays into light rays, a decay time (t1/10 = 5.5 us) short enough to permit repeated imaging with an interval of 1 ms, low phosphorescence, and high radiation stability. Because of the combination of these properties, they have become widely used in medical computerized tomography. Gadolinium oxysulfide (Gd2O2S) is also to produce phosphors and scintillation ceramics for color television picture tubes, medical imaging equipment, and up conversion luminescence, due to its wide-gap (4.6– 4.8eV), high chemical stability and high density. The present GOS scintillation ceramics are very promising as scintillator materials for X-ray CT detector applications.
Parameter
| Property | Value |
| Materials | Ge2O2S |
| Density (g/cm3) | 7.34 |
| Crystal structure | Hexagonal |
| Lattice parameters | a = b = 3.85827Å, c = 6.666659 Å |
| Hygroscopicity | No |
| Cleavage plane | No |
| Solubility (g/100gH2O) | N/A |
| Property | Value |
| Wavelength(Max. emission) (nm) | 510 |
| Wavelength range (nm) | 400-2000 |
| Decay time | 5.5 |
| Wide-Gap (eV) | 4.6-4.8 |
| Luminescence intensity (keV) | 27.5 |
| X-ray attenuation coefficient (cm-1) | 52 at 70 keV 0.80 at 500 keV |
| Relative light output (%) | 80 |
| Afterglow (%) | < 0.01 |
| Radiation damage (%) | -3 |
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| GOS Absorption Spectra | GOS Emission Spectra |
 | |
| GOS Transmission Spectra |
- High luminescence efficiency
- Low afterglow
- High light output
- High X-ray absorption efficiency
- X-ray CT
- X-ray microscope
- Laser materials
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