An alternative to polishing the surfaces of scintillation detectors [nuclear medicine application]

Experiments have been performed to evaluate the effect of a thin layer of low index of refraction epoxy applied to Lutetium Oxyorthosilicate crystals. Where possible, the results have been compared to chemical polishing/etching. It has been found that there is a significant improvement in energy resolution when cut crystal elements are treated with the epoxy, while the mean light output is unaffected. As the same effects were noted with scintillator blocks as with individual crystal elements, treatment with the low index of refraction epoxy may be of advantage in situations where etching is difficult to perform. These situations include negative acid and temperature effects on adhesives and detector assemblies. Once etched, applying the low index epoxy yields no light collecting benefit, but in all cases the epoxy provides a mechanically robust coating