BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY:Fiber-optic endomicroscopy for intrinsic nonlinear optical imaging
  of biological tissues
DTSTART:20100521T133000
DTSTAMP:20260411T111325Z
UID:42b6d7b00154038c9b4fb95cd19bd157388cf1ee9ca5f3a15b149991
CATEGORIES:Conferences - Seminars
DESCRIPTION:Yicong Wu\, Department of Biomedical Engineering\, Johns Hopki
 ns University\nIn this talk\, I will report on a fiber-optic scanning endo
 microscopy technology that enables intrinsic two-photon fluorescence (TPF)
  and second harmonic generation (SHG) imaging of biological tissues. There
  are many challenges in developing such a technology\, including single-mo
 de delivery of fs excitation pulses\, efficient collection of the nonlinea
 r optical signals\, an ultra-compact scanner for fast beam scanning\, and 
 high-quality miniature optics to handle the large separation between the e
 xcitation and TPF/SHG wavelengths. In our endomicroscope\, a double-clad f
 iber (DCF) was employed for single-mode fs pulse delivery and multimode TP
 F/SHG collection. The DCF also served as resonant cantilever driven by a P
 ZT actuator for fast 2D beam scanning. A miniature compound lens was devel
 oped to achieve a tight excitation focus\, reduce chromatic aberration and
  improve TPF/SHG collection. In addition\, a short multimode fiber was int
 roduced at the tip of the DCF to further mitigate the adverse effect of ch
 romatic aberration. TPF/SHG imaging of fluorescent beads demonstrated ~9 t
 imes improvement on TPF/SHG collection with the new design over a conventi
 onal GRIN lens based endomicroscope. Recently we have developed a customiz
 ed DCF of a larger inner-clad diameter to effectively suppress the backgro
 und TPF/SHG signal and improve the TPF/SHG collection efficiency\, thus gr
 eatly improving the signal-to-background ratio by a factor ~100. These tec
 hnological innovations have made possible to perform real-time two-photon 
 autofluorescence imaging and second harmonic generation of biological tiss
 ues for the first time with a fiber-optic endomicroscope. Our results show
  strong promise of the fiber-optic endomicroscopy technology for translati
 ng TPF/SHG microscopy to in vivo and clinical applications.
LOCATION:BM 5202 https://plan.epfl.ch/?room==BM%205202
STATUS:CONFIRMED
END:VEVENT
END:VCALENDAR