METHOD FOR SPACE-SELECTIVE CRYSTALLISATION OF GLASS Russian patent published in 2017 - IPC C03B32/02 C03C10/02 C03C3/15 

FIELD: chemistry.

SUBSTANCE: invention relates to optical materials science. Space-selective crystallisation of glass is induced by femtosecond laser. Laser beam is passed through a prism telescope or cylindrical lens to a focusing lens creating an elliptical cross-section beam waist with a major to minor axis ratio of at least 2:1, wherein the major axis is oriented along the crystal growth direction. The glass composition is as follows, mol %: La₂O₃ 23-26, B₂O₃ 23-26, GeO₂ 49-52 or La₂O₃ 20.9-26, B₂O₃ 23-27, GeO₂ 49-52, Nd₂O₃ 0.1-3. The beam movement speed along the glass is 10-50 mcm/s and laser pulse energy is within 0.5-2.5 mcJ.

EFFECT: achieved homogeneous crystal lines within the glass volume.

6 dwg, 3 ex