Self-Coated Single Crystal, And Production Apparatus And Process Therefor

摘要

It is an object of the present invention to provide a self-coated single crystal that without any special step conducted after crystal growth, has its circumference coated with a layer of different properties. A self-coated single crystal according to the present invention is characterized in that in operations comprising melting crystal materials for a core and a clad in a single crucible and carrying out growth of a single crystal through a pulling up method or a pulling down method, a grown single crystal in an as-growth condition has its circumference self-coated with a clad whose refractive index is lower than that of the core.