Patent ID: 7744696

Claim:
A method for producing a borate-based crystal, which comprises: employing a water-soluble cesium compound and a water-soluble boron compound as starting materials, dissolving all of the starting materials simultaneously in an amount of water which is 1.0 to 2.5 times the total weight of the starting materials, forming an aqueous solution with a uniform composition, evaporating the water in the aqueous solution, followed or not followed by sintering, to form a crystal growth material, melting the crystal growth material, and growing a cesium-borate-based crystal of the composition formula: Cs 1-x M x B 3 O 5 (0 ≦x< 1) wherein M is an alkaline metal or alkaline earth metal element, wherein the water-soluble cesium compound is a cesium carbonate compound, and wherein a decarboxylation reaction occurs in the aqueous solution by dissolving the starting materials in water.