Coherent Raman scanning fiber endoscopy.

Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Optics Letters (Impact Factor: 3.18). 07/2011; 36(13):2396-8. DOI: 10.1364/OL.36.002396
Source: PubMed

ABSTRACT Coherent Raman scattering methods allow for label-free imaging of tissue with chemical contrast and high spatial and temporal resolution. However, their imaging depth in scattering tissue is limited to less than 1 mm, requiring the development of endoscopes to obtain images deep inside the body. Here, we describe a coherent Raman endoscope that provides stimulated Raman scattering images at seven frames per second using a miniaturized fiber scanner, a custom-designed objective lens, and an optimized scheme for collection of scattered light from the tissue. We characterize the system and demonstrate chemical selectivity in mouse tissue images.

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