Publications related to Optical path length

3D diffractive optics for linear interconnects and nonlinear processing

The optical domain presents potential avenues for enhancing both computing and communication due to its inherent properties of bandwidth, parallelism, and energy efficiency. This research focuses on harnessing 3-Dimensional (3D) diffractive optics for nove ...

EPFL2024

Resonators with tailored optical path by cascaded-mode conversions

Ileana-Cristina Benea-Chelmus, Marco Piccardo

Optical resonators enable the generation, manipulation, and storage of electromagnetic waves. The physics underlying their operation is determined by the interference of electromagnetic waves, giving rise to the resonance spectrum. This mechanism causes th ...

Nature Portfolio2023

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

Demetri Psaltis, Abhijit Roy, Ahmed Ayoub

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

Observation of SQUID-Like Behavior in Fiber Laser with Intra-Cavity Epsilon-Near-Zero Effect

Camille Sophie Brès, Jiaye Wu, Marco Clementi, Qian Li, Xuanyi Liu

Establishing relations between fundamental effects in far-flung areas of physics is a subject of great interest in the current research. Realization of a novel photonic system akin to the radio-frequency superconducting quantum interference device (RF-SQUI ...

WILEY-V C H VERLAG GMBH2022

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

Vibration monitoring based on optical sensing of mechanical nonlinearities in glass suspended waveguides

Yves Bellouard, Tao Yang, Pieter Vlugter, Enrico Casamenti

Vibration monitoring plays a key role in numerous applications, including machinerypredictive maintenance, shock detection, space applications, packaging-integrity monitoring andmining. Here, we investigate mechanical nonlinearities inherently present in s ...

2021

System and methods for differential imaging using a lock-in camera

Christophe Moser, Timothé Laforest, Damien Claude-Marie Loterie, Chiara Bonati

The present invention describes an imaging system that allows visualization of a wide range of samples both in terms of morphology and in terms of material (e.g. density distribution, varying chemical composition, or anything that induces a change of optic ...

2021

Blue-shift ultrasensitivity using rhombus-shaped plasmonic crystal on Si3N4 membrane

Bahareh Ghadiani, Dordaneh Etezadi, Yasaman Jahani, Ershad Mohammadi, Foziyeh Sohrabi, Mahdi Tamizifar

Harnessing ultrasensitivity from optical structures to detect tiny changes in the targeted samples is the main goal of scientists in the field of sensor design. In this study, an uncommon rhombus-shape plasmonic structure is proposed for providing blue-shi ...

OPTICAL SOC AMER2020

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

Toralf Scharf, Wilfried Noell, 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

Light pattern generation with hybrid refractive microoptics under Gaussian beam illumination

Toralf Scharf, Maryam Yousefi

The generation of wide-angle diffraction patterns can be done in different ways using either thin diffractive optical elements with small features sizes or arrays of microoptics with large optical paths that are thick diffractive optical elements. Our aim ...

2020

Microfabrication of curved sidewall grooves using scanning nanosecond excimer laser ablation

Patrik Willi Hoffmann, André Gabriel Kostro, Jing Gong, Josef Andreas Schuler, Georgios Violakis

Novel glazing with embedded micro-mirrors can significantly reduce the energy consumption due to cooling and lighting in buildings. Especially promising are large arrays of periodic micro compound-parabolic-concentrators (CPCs) with angular-selected transm ...

SPIE2018

Electrochemical Imaging of Cells and Tissues

Hubert Girault, Tzu-En Lin, Andreas Stephan Lesch

The technological and experimental progress in electrochemical imaging of biological specimens is discussed with a view on potential applications for skin cancer diagnostics, reproductive medicine and microbial testing. The electrochemical analysis of sing ...

2018

Chip-Scale Frequency Comb Generators for High-Speed Communications and Optical Metrology

Tobias Kippenberg, Victor Brasch, Maxim Karpov, Arne Kordts

Chip-scale frequency comb sources are key elements for a variety of applications, comprising massively parallel optical communications and high-precision optical metrology. In this talk, we give an overview on our recent progress in the area of integrated ...

Spie-Int Soc Optical Engineering2017

Near-field characterization of Bloch surface waves based 2D optical components

Richa Dubey

Bloch surface waves (BSWs) are surface electromagnetic modes that propagate at the interface between a multilayer substrate and a homogeneous external medium. The optical field of the surface mode is confined near the surface of the multilayer. This vertic ...

EPFL2017

Soft Electrochemical Probes for Mapping the Distribution of Biomarkers and Injected Nanomaterials in Animal and Human Tissues

Hubert Girault, Horst Pick, Andreas Stephan Lesch, Tzu-En Lin, Yu Lu

Monitoring biomarkers and injected theranostic nanomaterials in tissues and organs plays a pivotal role in numerous medical applications ranging from cancer diagnostics to drug delivery. Scanning electrochemical microscopy has been demonstrated as a powerf ...

Wiley-Blackwell2017

Method and apparatus for measuring the local birefingence along an optical waveguide

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Xin Lu

This invention relates to a system and method to determine the distributed birefringence profile along an optical fibre. Birefringence manifests as different refractive indices for two orthogonal states of polarization of the light propagating in the optic ...

2016

Super-resolution imaging of multiple cells by optimized flat-field epi-illumination

Suliana Manley, Kyle Michael Douglass, Christian Sieben, Anna Archetti, Ambroise Justin Lambert

Biological processes are inherently multi-scale, and supramolecular complexes at the nanoscale determine changes at the cellular scale and beyond. Single-molecule localizationmicroscopy (SMLM)(1-3) techniques have been established as important tools for st ...

Nature Publishing Group2016

Photoacoustics with coherent light

Emmanuel André Henri Bossy

Since its introduction in the mid-nineties, photoacoustic imaging of biological tissue has been one of the fastest growing biomedical imaging modality, and its basic principles are now considered as well established. In particular, light propagation in pho ...

Elsevier Gmbh, Urban & Fischer Verlag2016

Multiscattering-Enhanced Absorption Spectroscopy

Christian Santschi, Olivier Martin, Volodymyr Koman

An original scheme for sensitive absorption measurements, particularly well-suited for low analyte concentrations, is presented. The technique is based on multiscattering-enhanced absorption spectroscopy (MEAS) and benefits from the advantages of conventio ...

Amer Chemical Soc2015

Brillouin dynamic gratings in optical fibres for distributed sensing and advanced optical signal processing

Andrey Denisov

This thesis presents results of a research on applications of Brillouin dynamic gratings - distributed reflectors that can be dynamically created in an optical fibre by two optical waves. A basic theory of stimulated Brillouin scattering (SBS) is introduce ...

EPFL2015