Leibniz Institute of Photonic Technology, Albert-Einstein-Str. 9, 07745 Jena, Germany
M. Schmitt
Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University Jena, Albert-Einstein-Str. 6, 07745 Jena, Germany
J. Popp
Leibniz Institute of Photonic Technology, Albert-Einstein-Str. 9, 07745 Jena, Germany
O. Uckermann
Neurosurgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany
R. Galli
Clinical Sensoring and Monitoring, Anesthesiology and Intensive Care Medicine, Faculty of Medicine, Technische Universität Dresden, 01307 Dresden, Germany
M. Kirsch
Neurosurgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany
M. J. Winterhalder
Department Chemie and Center for Applied Photonis, University of Konstanz, 78457 Konstanz, Germany
A. Zumbusch
Department Chemie and Center for Applied Photonis, University of Konstanz, 78457 Konstanz, Germany
Nonlinear optical endoscopy is an attractive technique for biomedical imaging since it promises to give access to high resolution imaging in vivo. Among the various techniques used for endoscopic contrast generation, coherent anti-Stokes Raman scattering (CARS) is especially interesting. CARS endoscopy allows molecule specific imaging of unlabeled samples. In this contribution, we describe the design, implementation, and experimental characterization of a rigid, compact CARS endoscope with a spatial resolution of 750 nm over a field of view of roughly 250 μm. Omission of the relay optics and use of a gradient index lens specifically designed for this application allow one to realize these specifications in an endoscopic unit which is 2.2 mm wide over a length of 187 mm, making clinical applications during surgical interventions possible. Multimodal use of the endoscope is demonstrated with images of samples with neurosurgical relevance.
