Publications associées à Interaction between Light, Paper and Color Halftones: Challenges and Modelization Approaches

Dielectric Elastomer Actuator-Based Valveless Impedance-Driven Pumping for Meso- and Macroscale Applications

Yves Perriard, Yoan René Cyrille Civet, Silje Ekroll Jahren, Thomas Guillaume Martinez, Francesco Clavica, Armando Matthieu Walter, Amine Benouhiba

Impedance pumps are simple designs that allow the generation or amplification of flow. They are fluid-filled systems based on flexible tubing connected to tubing with different impedances. A periodic off-center compression of the flexible tubing causes the ...

2023

Sensing of Surface and Bulk Refractive Index Using Magnetophotonic Crystal with Hybrid Magneto-Optical Response

Serguei Sekatski

We propose an all-dielectric magneto-photonic crystal with a hybrid magneto-optical response that allows for the simultaneous measurements of the surface and bulk refractive index of the analyzed substance. The approach is based on two different spectral f ...

2021

A phenomenological extended-reaction boundary model for time-domain wave-based acoustic simulations under sparse reflection conditions using a wave splitting method

Jan Sickmann Hesthaven

In environmental acoustics and in room acoustics, many surfaces exhibit extended-reaction (ER) behavior, i.e., their surface impedance varies with the angle of the incident sound wave. This paper presents a phenomenological method for modeling such angle d ...

ELSEVIER SCI LTD2021

Reciprocal Metasurfaces for On-axis Reflective Optical Computing

Karim Achouri, Romain Christophe Rémy Fleury, Ali Momeni

Analog computing has emerged as a promising candidate for real-time and parallel continuous data processing. This paper presents a reciprocal way for realizing asymmetric optical transfer functions (OTFs) in the reflection side of the on-axis processing ch ...

2021

Modeling specular transmission of complex fenestration systems with data-driven BSDFs

Jan Wienold

A Bidirectional Scattering Distribution Function (BSDF) describes how light from each incident direction is scattered (reflected and transmitted) by a simple or composite surface, such as a window shade. Compact, tabular BSDFs may be derived via interpolat ...

2021

Light Path Gradients for Forward and Inverse Rendering

Tizian Lucien Zeltner

Physically based rendering is a process for photorealistic digital image synthesis and one of the core problems in computer graphics. It involves simulating the light transport, i.e. the emission, propagation, and scattering of light through a virtual scen ...

EPFL2021

Ultra-Broadband and Omnidirectional Perfect Absorber Based on Copper Nanowire/Carbon Nanotube Hierarchical Structure

Giulia Tagliabue, Fateme Kiani Shahvandi, Theodoros Tsoulos

Zero reflection and complete light absorption are required in a wide range of applications ranging from sensing devices to solar heaters and photoelectrodes. However, simultaneously satisfying the requirements of the broadband spectrum, omnidirectionality, ...

AMER CHEMICAL SOC2020

Finite element modeling of dynamic frictional rupture with rate and state friction

Jean-François Molinari, Fabian Barras, Roozbeh Rezakhani, Michael Ludovic Brun

Numerous laboratory experiments have demonstrated the dependence of the friction coefficient on the interfacial slip rate and the contact history, a behavior generically called rate and state friction. Although numerical models have been widely used for an ...

PERGAMON-ELSEVIER SCIENCE LTD2020

On design strategies for binary dielectric metasurfaces based on the Fourier modal method

Kévin Müller

Binary dielectric metasurfaces are arrays of sub-wavelength structures that act as a thin layer of artificial material. They are generally lossless and relatively simple to fabricate since only a single structuring step is required. By carefully designing ...

EPFL2020

Effects of multiple scattering on angle-independent structural color in disordered colloidal materials

Sofia Magkiriadou

Disordered packings of colloidal spheres show angle-independent structural color when the particles are on the scale of the wavelength of visible light. Previous work has shown that the positions of the peaks in the reflectance spectra can be predicted acc ...

AMER PHYSICAL SOC2020

Reflection for action: designing tools to support teacher reflection on everyday evidence

Pierre Dillenbourg

Improving educational practice through reflection is one important focus of teacher professional development approaches. However, such teacher reflection operates under practical classroom constraints that make it happen infrequently, including the relianc ...

ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD2020

Wideband Multiport Antennas

Anja Skrivervik, Abdulkadir Uzun

In this paper, a wideband four port 2-6 GHz antenna is proposed. One-, two-, and four-port antennas are implemented and characterized between 2 and 6 GHz. The isolation between the ports is improved by connecting and optimizing the ground plane sections. T ...

2020

First mirror test in JET for ITER: Complete overview after three ILW campaigns

Patrick Blanchard, Basil Duval, Ambrogio Fasoli, Yves Martin, Richard Pitts, Olivier Sauter, Henri Weisen, Robin Humphry-Baker, Stefano Coda, Martinus Gijs, Partha Dutta, Marco Wischmeier, Jan Horacek, Vlad Trifa, Yann Camenen, Jonathan Graves, Duccio Testa, Miguel Fernández Ruiz, Sun Hee Kim, Mikhail Maslov, Javier García Hernández, David Pfefferlé, José Pedro Rebelo Ferreira Marques, Julio Rodriguez, Pedro Camilo de Oliveira e Silva, Rebecca Hill, Daniel Scott Alessi, Jonnathan Cesar Hidalgo Acosta, Ana Francisca Leal Silva Soares, Dalziel Joseph Wilson, Pierre-Thomas Paul Brun, Jonathan Marc Philippe Faustin, Federico Nespoli, Alberto Hernando de Castro, Hamish William Patten, Bruno Emanuel Ferreira De Sousa Correia, Li Shuai, Nicola Vianello, Antonio José Pereira de Figueiredo, , , , , , , , ,

Angular Color Prediction Model for Anisotropic Halftone Prints on a Metallic Substrate

Roger Hersch, Petar Pjanic, Lin Yang

Under specular reflection, non-isotropic halftones such as line halftones printed on an ink-receiving plastic layer superposed with a metallic layer change their colors upon in-plane rotation of the print. This color change is due to the orientation-depend ...

I S & T-SOC IMAGING SCIENCE TECHNOLOGY2019

Automated ‘Eye-sight’ Venetian blinds based on an embedded photometric device with real-time daylighting computing

Jean-Louis Scartezzini, Jérôme Henri Kämpf, Yujie Wu

Optimal shading control can improve occupants’ visual comfort and increase energy savings on artificial lighting and cooling loads during warm seasons. A highly integrated automated shading system is presented in this paper. Designed to regulate daylightin ...

2019

Embedded Polarizing Filters to Separate Diffuse and Specular Reflection

Gilles Baechler, Laurent Valentin Jospin, Adam James Scholefield

Polarizing filters provide a powerful way to separate diffuse and specular reflection; however, traditional methods rely on several captures and require proper alignment of the filters. Recently, camera manufacturers have proposed to embed polarizing micro ...

SPRINGER INTERNATIONAL PUBLISHING AG2019

Resonant Waveguide Gratings for Color-Selective Diffraction

Giorgio Quaranta

Resonant waveguide gratings (RWGs), also known as guided mode resonant (GMR) gratings or waveguide-mode resonant gratings, are dielectric structures where these resonant diffractive elements benefit from lateral leaky guided modes and can operate from UV t ...

EPFL2019

A smart luminaire in an office environment: impact on light distribution, user interactions and comfort

Jérôme Henri Kämpf

A smart luminaire able to change the direction of its light beam is installed in an office environment and compared to the available LEDs fixtures. Standard lighting measures are performed and a controlled user experiment is conducted, involving 22 subject ...

IOP Publishing Ltd2019

Toward Wideband Steerable Acoustic Metasurfaces with Arrays of Active Electroacoustic Resonators

Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Romain Christophe Rémy Fleury, Thomas Laurence

We introduce an active concept for achieving acoustic metasurfaces with steerable reflection properties, effective over a wide frequency band. The proposed active acoustic metasurface consists in a surface array of subwavelength loudspeakers diaphragms, ea ...

2018

Sampling the Multiple Facets of Light

Gilles Baechler

The theme of this thesis revolves around three important manifestations of light, namely its corpuscular, wave and electromagnetic nature. Our goal is to exploit these principles to analyze, design and build imaging modalities by developing new signal proc ...

EPFL2018