000229152 001__ 229152
000229152 005__ 20181205220335.0
000229152 0247_ $$2doi$$a10.5075/epfl-thesis-7799
000229152 02470 $$2urn$$aurn:nbn:ch:bel-epfl-thesis7799-7
000229152 02471 $$2nebis$$a10919205
000229152 037__ $$aTHESIS
000229152 041__ $$aeng
000229152 088__ $$a7799
000229152 245__ $$aMicroscopy and digital light shaping through optical fibers
000229152 260__ $$aLausanne$$bEPFL$$c2017
000229152 269__ $$a2017
000229152 300__ $$a139
000229152 336__ $$aTheses
000229152 502__ $$aProf. Hatice Altug (présidente) ; Prof. Christophe Moser (directeur de thèse) ; Prof. Demetri Psaltis, Prof. Sylvain Gigan, Dr Tomas Cizmar (rapporteurs)
000229152 520__ $$aMicroscopy is an essential tool in medicine and biomedical research. Traditional microscopes rely on bulky optics, complicating their usage when studying live animal tissues. In addition, light cannot penetrate very far in most biological tissues due to scattering, so typically only superficial tissues can be accessed non-invasively.     In this thesis, microscopic imaging was achieved through a single multimode optical fiber. Fibers are extremely thin (less than 300 µm) and guide light efficiently, so they provide a minimally invasive solution for microscopic imaging at any depth inside tissues.    Imaging via single fibers requires compensation of modal scrambling, an effect that distorts images in multimode fibers. The tool used in this thesis to control light and undo modal scrambling is the transmission matrix, a general framework that can describe the input-output relationship of any optical system very precisely. A procedure was developed to measure large transmission matrices accurately, based on digital holography and wavefront shaping with spatial light modulators. High-resolution image transmission through single fibers was subsequently demonstrated in a variety of configurations. Building on these results, confocal imaging was implemented in order to increase image contrast. Finally, the bending tolerance was investigated, and a set of conditions was identified under which fibers can be deformed without losing significant imaging performance.    Multimode fiber imaging is a promising solution for endoscopic microscopy. By compensating modal scrambling, it is possible to turn fibers into extremely thin microscopes with diffraction-limited resolution. This could be applied for example to assist in biopsies or for other minimally invasive imaging applications.
000229152 6531_ $$afiber optics imaging
000229152 6531_ $$amicroscopy
000229152 6531_ $$atransmission matrix
000229152 6531_ $$adigital holography
000229152 6531_ $$awavefront shaping
000229152 6531_ $$aspatial light modulators
000229152 700__ $$0247638$$aLoterie, Damien Claude-Marie$$g213838
000229152 720_2 $$0243489$$aMoser, Christophe$$edir.$$g199130
000229152 8564_ $$s9471152$$uhttps://infoscience.epfl.ch/record/229152/files/EPFL_TH7799.pdf$$yn/a$$zn/a
000229152 909C0 $$0252211$$pLAPD$$xU12209
000229152 909CO $$ooai:infoscience.tind.io:229152$$pthesis$$pthesis-bn2018$$pDOI$$pSTI$$qDOI2$$qGLOBAL_SET
000229152 917Z8 $$x108898
000229152 917Z8 $$x252028
000229152 918__ $$aSTI$$cIMT$$dEDPO
000229152 919__ $$aLAPD
000229152 920__ $$a2017-6-23$$b2017
000229152 970__ $$a7799/THESES
000229152 973__ $$aEPFL$$sPUBLISHED
000229152 980__ $$aTHESIS