| 摘要 |
PURPOSE:To obtain the titled fiber, suitable as solid microlaser elements, amplifying elements, etc., having a disturbed outer peripheral surface and capable of preventing occurrence of unnecessary mode, etc., by etching the outer periphery of a single crystal fiber of grown crystal. CONSTITUTION:A seed crystal is brought into contact with a starting raw material melt, such as a metallic oxide, e.g. LiNbO3, compound semiconductor, e.g. YAG (yttrium-aluminum-garnet), or alumina crystal substance, e.g. sapphire or ruby, pulled up and grown to provide a large-caliber polycrystal or single crystal, which is then cut and ground into a given diameter and length by a grinder, etc., to afford a preform crystal rod 1. The upper end of the rod is subsequently melted by heating with a heating means, such as laser, and the seed crystal is brought into contact the melt and slowly pulled up to a provide a single crystal fiber 2. The outside diameter of the resultant fiber 2 is measured by an outside diameter measuring instrument 3 and controlled within a given range on the basis of the measured data by a vapor etching device 4. The fiber is simultaneously heated at 1,300-1,700 deg.C and the outer peripheral surface thereof is etched with an etching gas, such as CF4, at 1-3mum/min etching quantity to provide a disturbed surface.
|
