eprintid: 4836
rev_number: 8
eprint_status: archive
userid: 1
dir: disk0/00/00/48/36
datestamp: 2004-08-17 10:27:28
lastmod: 2014-04-03 13:58:57
status_changed: 2012-08-14 15:12:42
type: doctoralThesis
metadata_visibility: show
creators_name: Feierabend, Marcus
title: Coherence-Gated Wave-Front Sensing in Strongly Scattering Samples
title_de: Kohärenzgatter-Wellenfrontabtastung in stark streuenden Proben
ispublished: pub
subjects: ddc-530
divisions: i-851330
adv_faculty: af-13
keywords: Optische KohärenztomographieAdaptive Optics , Wave-Front Sensing , Coherence , Optical Coherence Tomography , Fluorescence Microscopy
cterms_swd: Adaptive Optik
cterms_swd: Wellenfront
cterms_swd: Wellenfrontsensor
cterms_swd: Optische Kohärenz
cterms_swd: Fluoreszenzmikroskopie
abstract: In this thesis coherence-gated wave-front sensing (CGWS), a new approach for measuring wave-fronts in strongly scattering samples, is presented. This method combines Shack-Hartmann wave-front sensing and phase shifting interferometry (PSI). It employs virtual lenses to mimic the function of a conventional Shack-Hartmann sensor. The use of a modal estimation algorithm allows an approximation of the measured wave-front with a linear combination of Zernike polynomials up to the fifth radial degree. The principle of CGWS is tested by measuring two wave-front aberrations, defocus and astigmatism, for a mirror as a sample and a strongly scattering sample. The results are compared to theoretical models. The main advantage of CGWS is the discrimination against light backscattered from outside the focal region. A further advantage is the increase in the effective detection sensitivity. The capabilities of CGWS are demonstrated with wave-front measurements in scattering samples in the presence of background light that is dominant by about three orders of magnitude. In various microscopy applications, the ability to pre-emptively correct the wave-front, employing CGWS measurement data, may allow improvements of the optical focus and thus enhance the resolution and depth penetration in tissue considerably.
abstract_translated_lang: eng
date: 2004
date_type: published
id_scheme: DOI
id_number: 10.11588/heidok.00004836
ppn_swb: 1643811096
own_urn: urn:nbn:de:bsz:16-opus-48368
date_accepted: 2004-06-30
advisor: HASH(0x55a9a646eac0)
language: eng
bibsort: FEIERABENDCOHERENCEG2004
full_text_status: public
citation:   Feierabend, Marcus  (2004) Coherence-Gated Wave-Front Sensing in Strongly Scattering Samples.  [Dissertation]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/4836/1/MarcusFeierabendPhDThesis.pdf