Article

Compression of fiber supercontinuum pulses to the Fourier-limit in a high-numerical-aperture focus.

Biophotonics Imaging Laboratory, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Optics Letters (Impact Factor: 3.18). 06/2011; 36(12):2315-7. DOI: 10.1364/OL.36.002315
Source: PubMed

ABSTRACT A multiphoton intrapulse interference phase scan (MIIPS) adaptively and automatically compensates the combined phase distortion from a fiber supercontinuum source, a spatial light modulator pulse shaper, and a high-NA microscope objective, allowing Fourier-transform-limited compression of the supercontinuum pulses at the focus of the objective. A second-harmonic-generation-based method is employed to independently validate the transform-limited compression. The compressed pulses at the focus of the objective have a tunable duration of 10.8-38.9 fs (FWHM), a central wavelength of ~1020 nm, an average power of 18-70 mW, and a repetition rate of 76 MHz, permitting the application of this source to nonlinear optical microscopy and coherently controlled microspectroscopy.

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