Fabrication of micro-optical components by using a femtosecond laser

Abstract

Femtosecond laser has been widely used in materials micro-processing when high accuracy and small structure size are required. When a transparent material like glass is irradiated by a tightly focused femtosecond laser, the photoinduced reaction is expected to occur only near the focused part of the laser beam due to the multiphoton processes. We observed various induced structures e.g. color center defects, refractive index change, micro-void and micro-crack, in glasses after the femtosecond laser irradiation. Here, we demonstrate the fabrication of various micro-optical components, e.g. optical waveguide, microgating, microlens, fiber attenuator, 3-dimensional optical memory by using the femtosecond laser-induced structures. The femtosecond laser direct writing technique is very promising in the fabrication of micro-optical components with various optical functions.