| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for growing crystal to stably and at high probability obtain a fluoride crystal, etc., free from sub-grain boundary on its crystal face 111}, a method for forming a fluoride crystal, a forming method for an optical member, and a seed crystal used for the forming method. SOLUTION: In the method for growing crystal, growing of crystal is conducted as follows: On the process of crystallizing a molten raw material, the solid-liquid interface is made to be convex and the crystalline lattice distortion on growing of crystal is controlled in the direction making the distortion to reach an external surface of the crystal. The face orientation of the crystal grown continuously is changed to such an extent that a grain boundary is generated, and the energy of the crystalline lattice distortion is all released. Thus, a crystal growth face 111} free from crystalline lattice distortion from the crystal grain boundary face is obtained.
|
