title: Vibrational phase imaging in wide-field CARS for nonresonant background suppression.
abstract: Coherent Anti-Stokes Raman Scattering (CARS) microscopy is a valuable tool for label-free imaging of biological samples. As a major drawback quantification based on CARS images is compromised by the appearance of a nonresonant background. In this paper we propose and demonstrate a wide-field CARS vibrational phase imaging scheme that allows for nonresonant background suppression. Several CARS images at a few consecutive planes perpendicular to the propagation direction were recorded to reconstruct a phase map utilizing the iteration phase retrieval method. Experimental results verify that the CARS background is efficiently suppressed by the phase imaging approach, as compared to traditional CARS imaging without background correction. The proposed background correction method is robust against environmental disturbance, since the experimental implementation of the suggested detection scheme requires no reference beam.
authors.forename: Juanjuan
authors.initials: J
authors.lastname: Zheng
authors.forename: Denis
authors.initials: D
authors.lastname: Akimov
authors.forename: Sandro
authors.initials: S
authors.lastname: Heuke
authors.forename: Michael
authors.initials: M
authors.lastname: Schmitt
authors.forename: Baoli
authors.initials: B
authors.lastname: Yao
authors.forename: Tong
authors.initials: T
authors.lastname: Ye
authors.forename: Ming
authors.initials: M
authors.lastname: Lei
authors.forename: Peng
authors.initials: P
authors.lastname: Gao
authors.forename: Jürgen
authors.initials: J
authors.lastname: Popp