Abstract: Φ125 mm×180 mm optics-grade sapphire single crystal with mass of 6 kg were grown by Kyropous method. The crystal is transparent, colourless and no visible scattering particle under green ligthing. Especially it have attractive quality such as optical homogeneity of 2.1×10~(-7), and no detected stress stripes both in the a and c directions.

Key words: Φ125 mm×180 mm optics-grade sapphire single crystal with mass of 6 kg were grown by Kyropous method. The crystal is transparent, colourless and no visible scattering particle under green ligthing. Especially it have attractive quality such as optical homogeneity of 2.1×10~(-7), and no detected stress stripes both in the a and c directions.