Low voltage cathodoluminescent properties of phosphors coated with In2O3 by sol-gel method

The phosphors used in usual CRTs are difficult to be used in a lower voltage than 500 V, because of charging-up on their surfaces. ZnS:Ag, Cl phosphor was coated with In2O3 using indium-iso-propoxide by the sol-gel method. It was found that a very thin In2O3 conductive layer could be coated uniformly on the phosphor surface. The low voltage cathodoluminescent properties were studied and compared with those without In2O3. The luminance of the phosphor excited with an electron beam of lower voltage than 500 V was considerably improved. Moreover, it was found that the formation of the thin layer is also quite effective for the improvement of the aging characteristics of cathodoluminescence.