title: Beam scanning for rapid coherent Raman hyperspectral imaging.
abstract: Coherent Raman imaging requires high-peak power laser pulses to maximize the nonlinear multiphoton signal generation, but accompanying photo-induced sample damage often poses a challenge to microscopic imaging studies. We demonstrate that beam scanning by a 3.5-kHz resonant mirror in a broadband coherent anti-Stokes Raman scattering (BCARS) imaging system can reduce photo-induced damage without compromising signal intensity. Additionally, beam scanning enables slit acquisition, in which spectra from a thin line of sample illumination are acquired in parallel during a single charge-coupled device exposure. Reflective mirrors are employed in the beam-scanning assembly to minimize chromatic aberration and temporal dispersion. The combined approach of beam scanning and slit acquisition is compared with the sample-scanning mode in terms of spatial resolution, photo-induced damage, and imaging speed at the maximum laser power below the sample-damage threshold. We show that the beam-scanning BCARS imaging method can reduce photodamage probability in biological cells and tissues, enabling faster imaging speed by using a higher excitation laser power than could be achieved without beam scanning.
authors.forename: Ian Seungwan
authors.initials: IS
authors.lastname: Ryu
authors.forename: Charles H
authors.initials: CH
authors.lastname: Camp
authors.forename: Ying
authors.initials: Y
authors.lastname: Jin
authors.forename: Marcus T
authors.initials: MT
authors.lastname: Cicerone
authors.forename: Young Jong
authors.initials: YJ
authors.lastname: Lee
mesh_terms: D016475:3T3 Cells; D000818:Animals; D051379:Mice; D061848:Optical Imaging / Q000379:methods*; D011137:Polystyrenes; D013059:Spectrum Analysis, Raman; D013997:Time Factors
chemical_list: D011137:Polystyrenes