Nonlinear Optical Microscopy and Spectroscopy Employing Octave Spanning Pulses

This paper reviews and discusses the concept of nonlinear optical spectroscopy (NLOS) and microscopy employing ultra-broadband laser pulses. A spectral phase modulation technique of the ultra-broadband pulses, which allows the control of nonlinear optical processes, enables multimodal imaging in nonlinear optical microscopy. This technique uses the difference of the excitation spectra of molecules of interest. A spectroscopic technique combining NLOS with a Fourier-transform (FT) spectroscopy provides a broadband excitation spectrum with the bandwidth of the ultra-broadband pulse and a high spectral resolution in a single measurement. FT-NLOS can also be applied directly to multispectral microspectroscopy.