METHOD OF MAKING BULK WAVEGUIDE Russian patent published in 2014 - IPC G02B6/10 C03C23/00 H01P11/00 

FIELD: physics, optics.

SUBSTANCE: invention relates to the technology of producing optical waveguides, i.e., light-conducting and light-controlling structures, placed in a glass volume. The method of making a bulk waveguide includes moving a focused laser beam relative to a plate or a plate relative to a focused laser beam until the completion of formation of the waveguide and subsequent heat treatment of the plate with the waveguide in a furnace. Before forming the waveguide, a plate of porous optical material is placed in a chamber in which, at room temperature, relative air humidity is kept not lower than 60% and not higher than 80% for not less than 72 hours but not more than 96 hours. Local laser action is carried out by a focused laser beam in the plane of a layer lying at a depth equal to j the thickness of the plate, with power density not lower than 1.5·10⁴ W/cm² and not higher than 2.5·10⁴ W/cm². Movement of the focused laser beam relative to the plate or the plate relative to the focused laser beam is carried out with a speed of not less than 3 mcm/s but not greater than 20 mcm/s multiple times until the waveguide is formed. The plate with the waveguide then undergo heat treatment at temperature not lower than 870°C but not higher than 890°C for not less than 10 min and not more than 20 min, wherein heating of the plate with the waveguide to temperature not higher than 140°C is carried out at a rate of not more than 5°C/min, and the plate with the waveguide is cooled after heat treatment by turning off the furnace.

EFFECT: higher distinction between refraction indices of the core and cladding and reduced losses of the optical signal transmitted through the waveguide.

15 dwg