Abstract
We report on a refractive index modification (▵n) induced by femtosecond irradiation and evaluation of the profile for created lines inside the different types of optical glasses, i.e., silicate or borate glass containing the metal oxides such as BaO, TiO<sub>2</sub>, or La<sub>2</sub>O<sub>3</sub> and silica glass. The lines are fabricated by scanning a stage and focusing the femtosecond laser pulses, 800nm wavelength, a 250 kHz repetition rate and 200 fs pulse duration, from the Ti:sapphire regenerative amplifier system. The ▵n profiles of modification were obtained with Qualitative Phase Microscopy technique and presented systematically for a different input power and a variety of glasses. The ▵n profile changed with focusing condition using 10× (N.A.=0.3) or 40× (N.A.=0.85), and input power in a single glass. However, the ▵n and a trend of the sign was different depending on glass types. For example, silicate glass containing TiO<sub>2</sub>, exhibited negative ▵n trend the ▵n became smaller in the modified region. Furthermore, the glass showed relatively large negative ▵n, < - 0.01 decrease of the ▵n, ▵n < -0.01, in the investigated power range. These results could be useful for a design or use of glasses for micro optics, such as grating, diffractive lens or lens array, produced by femtosecond laser fabrication.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.