Title :
Micro-welding of glass by fs-laser irradiation and process observation using fs-pump-probe white light interference microscopy
Author :
Wortmann, D. ; Mingareev, I. ; Brand, A. ; Horn, A.
Author_Institution :
Lehrstuhl fur Lasertech., RWTH Aachen Univ., Aachen, Germany
Abstract :
A technique for a time resolved in-situ measurement of the optical phase and therefore the refractive index in the material was developed. A modified Mach-Zehnder interferometer combined with microscope objectives is used for the measurement of phase changes in the processed material sample. The white light is generated by focusing 80 fs-laser pulses in a sapphire crystal using a micro-lense array to minimize temporal and spatial fluctuations in the white-light continuum. The optical phase shift and therefore the refractive index of the material are calculated from the interference images. The change in refractive index during welding induced by heating and by compression of the glass has been detected with a temporal resolution in the ps-range and a spatial resolution of several microns.
Keywords :
Mach-Zehnder interferometers; glass; laser beam effects; laser beam welding; refractive index; Mach-Zehnder interferometer; SiO2; fs-laser irradiation; fs-pump-probe white light interference microscopy; glass; micro-welding; optical phase shift; refractive index; spatial fluctuations; Crystalline materials; Glass; Interference; Microscopy; Optical interferometry; Optical materials; Optical refraction; Phase change materials; Phase measurement; Refractive index;
Conference_Titel :
Lasers and Electro-Optics 2009 and the European Quantum Electronics Conference. CLEO Europe - EQEC 2009. European Conference on
Conference_Location :
Munich
Print_ISBN :
978-1-4244-4079-5
Electronic_ISBN :
978-1-4244-4080-1
DOI :
10.1109/CLEOE-EQEC.2009.5192327