Three-dimensional second-harmonic generation imaging with femtosecond laser pulses.
A three-dimensional reflectance scanning optical microscope based on the nonlinear optical phenomenon of second-harmonic generation is presented. A mode-locked Ti:sapphire laser producing <90-fs pulses at approximately 790 nm was used, and the images were constructed by scanning of an object, which possessed local second-order nonlinearity, relative to a focused spot from the laser. The second-harmonic light at approximately 395 nm generated by the specimen was separated from the fundamental beam by use of dichroic and interference filters and was detected by a photodiode. The technique was then used to characterize the distribution of second-order nonlinearity and microstructure of the nonlinear material lithium triborate.
Gauderon
R
R
Department of Physical Optics, School of Physics A28, University of Sydney, Sydney, New South Wales 2006, Australia.
Lukins
P B
PB
Sheppard
C J
CJ