ATu3P.1.pdf
CLEO:2014 © 2014 OSA
Laser Sources for Deep Tissue Multiphoton Imaging Chris Xu School of Applied and Engineering Physics at Cornell University, Ithaca, NY 14853, USA Author e-mail address:
[email protected]
Abstract: Deep tissue multiphoton microscopy (MPM) using solitons generated from optical fibers are reviewed. The main characteristics of the excitation source for deep tissue MPM, such as wavelength, pulse energy, and repetition rate, are discussed. OCIS codes: (060.4370) Nonlinear optics, fibers (180.0180) Microscopy
Optical imaging plays a major role in both basic biological research and clinical diagnostics, providing non-invasive or minimally invasive microscopic imaging capability to investigate biological tissues. Optical image acquisition through significant depths of biological tissues, however, presents a major challenge since tissue is extremely heterogeneous and the strong scattering of the various tissue components has restricted high-resolution optical imaging to superficial layers. Multiphoton microscopy (MPM), because of its 3D excitation confinement and long wavelength excitation, has significantly extended the penetration depth of high-resolution optical imaging, particularly for in vivo applications. Multiphoton imaging critically depends on ultrafast technologies, particularly pulsed excitation sources. Indeed, the dramatic advancement and the widespread applications of MPM in the last two decades are largely propelled by the development of ultrafast laser sources. In this paper, the basics of deep tissue MPM and its improvements utilizing soliton self-frequency shift (SSFS) are reviewed. Wavelength tunable, high-energy soliton generation through SSFS in large-mode-area (LMA) fibers and photonic crystal (PC) rods is presented. The application of these solitons to MPM enables non-invasive imaging in biological tissues with unprecedented depth. The main characteristics of the excitation source for deep tissue MPM, such as wavelength, pulse energy, and repetition rate, are discussed. References 1. Wang, K. and C. Xu, Appl. Phys. Lett., 99, 071112, 2011. 2. Horton, N.G., K. Wang, D. Kobat, C. Clark, F. Wise, C. Schaffer, and C. Xu, Nature Photon., 2013. 7, 205 (2013) 3. Xu, C. and F. W. Wise, Nature Photon., 7, 875–882, 2013
