Glass processing using femtosecond and nanosecond pulsed lasers

Abstract

Laser processing of glass components is of significant commercial interest for the optoelectronics and telecommunications industries. Several fundamentally different interactions are employed to produce active components: after generating optical waveguides and gratings inside glass, external features must be machined in the modules to allow light to couple into the functional regions. In this paper, we present laser processing techniques using microsecond, nanosecond, and femtosecond lasers for surface and sub-surface glass modification. A regeneratively amplified Ti-Sapphire laser operating at a near-IR wavelength with femtosecond pulses and a 250 kHz repetition rate is used to generate 3-D optical waveguides and Bragg gratings in glass and silica substrates. Surface structures, mainly groove geometries, are generated with a diode-pumped solid-state nanosecond pulsed UV laser operating at 266 nm, a Q-switched CO₂ laser operating at 9.25 μm, a CO₂ laser operating at 10.6 μm and the femtosecond pulsed laser operating at 800 nm. The material interactions are examined with respect to the differences in time scale and the appropriateness of each laser type for particular processes.