title: Measurement of group delay dispersion of high numerical aperture objective lenses using two-photon excited fluorescence.
abstract: We determined the group-delay dispersion (GDD) of five microscope objectives by measuring the second-order autocorrelation at the focal points of the objectives with two-photon excited fluorescence as the power square sensor. We found that typical microscope lens systems introduce significant GDD (2000-6500 fs(2)). The third-order dispersion determined for these objectives limits the minimum obtainable pulse width at the focal point of an objective to 20-30 fs if not compensated. No significant chromatic aberration or higher-order dispersion effects were found for any of the optical components measured within the wavelength range of 700-780 nm and for pulse widths greater than 50-60 fs.
authors.forename: J B
authors.initials: JB
authors.lastname: Guild
authors.forename: C
authors.initials: C
authors.lastname: Xu
authors.forename: W W
authors.initials: WW
authors.lastname: Webb