RARE EARTH-CALCIUM-OXYBORATE-BASED CRYSTAL AND METHOD OF PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide rare earth-calcium-oxyborate-based crystal which is greatly reduced in degree of optical damage due to irradiation with ultraviolet light and whose composition is close to a stoichiometry ratio, and a method of producing the same.;SOLUTION: A burned product of starting raw materials which are mixed at or nearly at the stoichiometry ratio is crushed and after zinc oxide is added, they are mixed again and burnt to produce a crystal growth raw material, which is used and grown to produce rare earth-calcium-oxyborate-based crystal such that a mol ratio of (M₁+M₂):Ca:B is 1:(3.96 to 4.05):(2.95 to 3.15) in a general formula M¹xM²_1-xCa₄O(BO₃)₃ (where M¹ and M² represent one or more kinds of different rare earth elements and 0≤X1).;COPYRIGHT: (C)2006,JPO&NCIPI