title: Two-photon fluorescence microscope with a hollow-core photonic crystal fiber.
abstract: Self-phase-modulation and group velocity dispersion of near IR femtosecond pulses in fibers restrict their use in two-photon fluorescence microscopy (TPFM). Here we demonstrate a hollow-core photonic crystal fiber based two-photon fluorescence microscope with low nonlinearity and dispersion effects. We use this fiber-based TPFM system to take two-photon fluorescence (chlorophyll) images of mesophyll tissue in the leaf of Rhaphidophora aurea. With less than 2mW average power exposure on the leaf at 755nm, the near zero-dispersion wavelength, chloroplasts distribution inside the mesophyll cells can be identified with a sub-micron spatial resolution. The acquired image quality is comparable to that acquired by the conventional fiber-free TPFM system, due to the negligible temporal pulse broadening effect.
authors.forename: Shih-Peng
authors.initials: SP
authors.lastname: Tai
authors.forename: Ming-Che
authors.initials: MC
authors.lastname: Chan
authors.forename: Tsung-Han
authors.initials: TH
authors.lastname: Tsai
authors.forename: Shi-Hao
authors.initials: SH
authors.lastname: Guol
authors.forename: Li-Jin
authors.initials: LJ
authors.lastname: Chen
authors.forename: Chi-Kuang
authors.initials: CK
authors.lastname: Sun