SPIE Student Chapter

Seminar Series

hosted by the Institute of Optics

“Second Harmonic Generation Microscopy”

Xiaoxing Han

Graduate Student

Institute of Optics

University of Rochester Medical Center

Tuesday, 11 August 2009

11:00 AM - 12:00 PM

Sloan Auditorium, Room 101, Goergen Hall

University of Rochester

Abstract

Second Harmonic Combination (SHG) is the non-absorptive combination of two excitation photons into one emission photon within a non-centrosymmetric medium such as a crystal surface, or properly ordered fibers. In practice, SHG microscopy is quite similar to Two Photon Excitation Fluorescence (TPEF) microscopy. However, there is acrucial difference between SHG and TPEF. SHG is based onscattering, meaning that it is a coherent phenomenon, whereas TPEF is based on fluorescence (i.e. absorption followed by emission),meaning that it is incoherent. My research work is focused onexploiting these coherent properties of SHG emission to study the molecule structure of collagen fiber in tumor Extra Cellular Matrix (ECM). The two coherent properties I used to study tumor collagen molecule structures are polarization and the ratio of forward vs. backward propagating SHG