Characterization of fiber ultrashort pulse delivery for nonlinear endomicroscopy.

A Ibrahim,R Habert,F Poulon,C Lefort,D Abi Haidar,A Kudlinski

doi:10.1364/oe.24.012515

Abstract

In this work, we present a detailed characterization of a small-core double-clad photonic crystal fiber, dedicated and approved for in vivo nonlinear imaging endomicroscopy. A numerical and experimental study has been performed to characterize the excitation and collection efficiencies through a 5 m-long optical fiber, including the pulse duration and spectral shape. This was first done without any distal optics, and then the performances of the system were studied by using two kinds of GRIN lenses at the fiber output. These results are compared to published data using commercial double clad fibers and GRIN lenses.

Highlights

Two-Photon Microscopy (TPM) has become a standard technique extensively used for imaging optically thick biological tissues [1]
By using the shortest pulse possible at the laser cavity output, combined to a GRISM line, we were able to reach a pulse duration of 33 fs at the output of a 5 m endomicroscopic customized fiber without a miniaturized GRIN lens, and 40 fs at the output of the fiber coupled to a miniaturized GRIN lens
We have demonstrated that our setup is able to compensate for the dispersion through such long fibers, and to provide pulses as short as those obtained with 1-meter-long fibers

Summary

Introduction

Two-Photon Microscopy (TPM) has become a standard technique extensively used for imaging optically thick biological tissues [1]. A more dedicated solution to study in vivo and in situ human tissues could be nonlinear endomicroscopy It presents the advantages of TPM and gives the possibility to an in vivo and in situ tissues imaging without resorting to a surgical biopsy, thanks to the use of a thin and elongated optical fiber coupled with miniaturized objective lens instead of the microscope objective. It allows less invasive tests and earlier detection of diseases

Methods

Results

Conclusion