| 摘要 |
PURPOSE:To obtain rutile single crystal sufficient as an optical material causing no light scattering, by using a raw material crystal rod obtained by melting and solidifying titanium dioxide, and growing single crystal by condensing heat type floating method. CONSTITUTION:A crystal rod obtained by melting and solidifying titanium dioxide as a raw material rod is used as a raw material rod, and single crystal is grown by condensing heat type floating method. Further, a single crystal rod by Verneuil's method is used as a raw material rod obtained by melting and solidifying titanium dioxide, and single crystal is grown by the condensing heat type floating method, to give more improved results. In producing the single crystal, the tip of the single crystal rod as seed crystal is brought into contact with the tip of the raw material rod, both the tips are placed on the focus of a condensing heat type floating device, melted, the melting point is gradually transferred, and the raw material rod is converted into the single crystal rod. In the operation, the melting is preferably carried out in an oxidizing atmosphere, so that oxygen defect will not cause in the single crystal. |
