Publications associées à Apertureless near-field optical microscopy: Differences between heterodyne interferometric and non-interferometric images

Subsurface fluorescence time-of-flight imaging using a large-format single-photon avalanche diode sensor for tumor depth assessment

Claudio Bruschini, Edoardo Charbon, Arin Can Ülkü, Yichen Feng

Significance: Fluorescence guidance is used clinically by surgeons to visualize anatomical and/or physiological phenomena in the surgical field that are difficult or impossible to detect by the naked eye. Such phenomena include tissue perfusion or molecula ...

SPIE Society of Photo-optical Instrumentation Engineers2024

High sensitivity, incoherent differential imaging

Chiara Bonati

Microscopic visualisation of optically transparent samples has been a topic of interest for several decades. Features such as density or chemical composition can influence the optical phase of transmitted light, and phase contrast can reveal these structur ...

EPFL2022

Optical Diffraction Tomography Using Nearly In-Line Holography with a Broadband LED Source

Demetri Psaltis, Ahmed Ayoub, Abhijit Roy

We present optical tomography methods for a 3D refractive index reconstruction of weakly scattering objects using LED light sources. We are able to record holograms by minimizing the optical path difference between the signal and reference beams while sepa ...

MDPI2022

Tunable acousto-optic optical frequency combs

Andrey Voloshin

Examination of various issues related to the generation and application of optical frequency combs (OFCs) is an important branch of modern optoelectronics. Some of the proposed OFC generation methods apply acousto-optic (AO) devices. The AO devices are use ...

Optica Publishing Group2022

Structured light generation by refractive-diffractive micro optical array illuminators

Maryam Yousefi

Structured light generation having broad applications in different optical fields, is the topic of this thesis. Our structured light generation strategy is based on applying periodic microoptical elements at the refraction-diffraction limit, under a focuse ...

EPFL2021

QUAREP-LiMi: A community-driven initiative to establish guidelines for quality assessment and reproducibility for instruments and images in light microscopy

Andrea Bassi, Antje Keppler, Arne Seitz

A modern day light microscope has evolved from a tool devoted to making primarily empirical observations to what is now a sophisticated , quantitative device that is an integral part of both physical and life science research. Nowadays, microscopes are fou ...

WILEY2021

Physics of optically driven nanojunctions

Philippe Andreas Rölli

Recent years have seen spectacular developments in the domain of nano-optics. Alongside the well-known techniques of super-resolution microscopy progress in nanofabrication has enabled important improvements in the fields of optical imaging and spectros ...

EPFL2020

Optical characterization of high numerical aperture microlenses for quality assessment and fabrication process optimization

Wilfried Noell, Toralf Scharf, Jeremy Béguelin

Accurate characterization of high numerical aperture aspheric microlenses currently is a nonstandard procedure that remains an open challenge. Here, we present and discuss a characterization method based on interferometric and point spread function measure ...

OPTICAL SOC AMER2020

Development of novel experimental and computational methods for three-dimensional coherent and super-resolution microscopy

Adrien Charles-François Raymond Descloux

Optical microscopy is one widely used tool to study cell functions and the interaction of molecules at a sub-cellular level. Optical microscopy techniques can be broadly divided into two categories: partially coherent and incoherent. Coherent microscopy te ...

EPFL2020

Phase resolved characterization of nanoscale features in optical microstructures

Michail Symeonidis

In this study, we apply interferometric microscopy to study the phase, alongside the intensity, of the light field transmitted through a wide variety of samples. Additionally, we conduct those interferometric measurements at different wavelengths within th ...

EPFL2019

Label-free, scalable and point-of-care imaging platform for rapid analysis of biomarker

Hatice Altug, Alexander Belushkin, Filiz Yesilköy, Yasaman Jahani

We propose a disruptive point-of-care (PoC) imaging platform based on lens-free interference phase-contrast imaging for rapid detection of biomarker such as for sepsis and potentially other diseases (e.g. cancer). It enables simultaneous analysis of potent ...

SPIE-INT SOC OPTICAL ENGINEERING2019

Biomedical optical techniques for intracochlear cellular imaging

Marilisa Romito

Imaging the inner ear microanatomy is of great importance for the assessment of the state of the cells responsible for sound detection. Hearing disorders are mainly due to a malfunction of the cochlea, the bone containing the cells inside the inner ear. Un ...

EPFL2019

High-resolution interference microscopy with spectral resolution for the characterization of individual particles and self-assembled meta-atoms

Toralf Scharf, Michail Symeonidis, Andreas Vetter

We apply a high-resolution interference microscope with spectral resolution to investigate the scattering response of isolated meta-atoms in real space. The final meta-atoms consist of core-shell clusters that are fabricated using a bottom-up approach. The ...

2019

High-resolution interference microscopy of binary phase diffractive optical elements

Toralf Scharf, Michail Symeonidis, Dong Cheon Kim

In this work, we apply the high-resolution interference microscopy technique to investigate the intensity and phase of light transmitted through a binary phase element. Using a combination of simulation and experimental results, we identify specific featur ...

2019

Measurement of Displacement and Its Derivatives from a Phase Fringe Pattern

Pramod Rastogi, Rishikesh Dilip Kulkarni

Noting the fact that the phase and phase derivatives carry the information on the mechanical deformation in optical interferometric measurements techniques, we propose a noise robust fringe analysis technique for the simultaneous estimation of unwrapped ph ...

SPRINGER INTERNATIONAL PUBLISHING AG2019

Structural and functional brain imaging using extended-focus optical coherence tomography and microscopy

Paul James Marchand

Neuroimaging techniques aim at revealing the anatomy and functional organisation of cerebral structures. Over the past decades, functional magnetic resonance imaging (fMRI) has revolutionized our understanding of human cerebral physiology through its abili ...

EPFL2018

Tomographic imaging with harmonic holography in tissues of known refractive index distribution

Demetri Psaltis, Ye Pu

High-resolution imaging in thick biological tissues beyond a few transport mean free path of photons remains a formidable challenge to modern science and technology. Recent advancements in optical tomography have enabled the reconstruction of the three-dim ...

SPIE-INT SOC OPTICAL ENGINEERING2018

Dielectric-sphere-based microsystem for optical super-resolution imaging

Gergely Huszka

Well-established imaging techniques proved that features below the diffraction limit can be observed optically using so-called super-resolution microscopies, which overcome Abbe's resolution limit. In traditional far-field microscopy, the introduction of f ...

EPFL2018

Direct unwrapped phase estimation in phase shifting interferometry using Levenberg-Marquardt algorithm

Pramod Rastogi, Rishikesh Dilip Kulkarni

An algorithm for the direct unwrapped phase estimation from the linearly phase shifted interferograms is presented. The temporal fringe intensity along each pixel is represented as a function of fringe amplitude, phase step and the searched phase. These pa ...

Iop Publishing Ltd2017

Label-free three-dimensional imaging of Caenorhabditis elegans with visible optical coherence microscopy

Theo Lasser, Paul James Marchand, Séverine Coquoz, Johan Auwerx, Arno Pino Bouwens, Laurent Mouchiroud, Daniel Pawel Szlag, Vincenzo Sorrentino

Fast, label-free, high-resolution, three-dimensional imaging platforms are crucial for high-throughput in vivo time-lapse studies of the anatomy of Caenorhabditis elegans, one of the most commonly used model organisms in biomedical research. Despite the ne ...

Public Library of Science2017