Publications associées à Simple and easily controllable parabolic-shaped microlenses printed on polymeric mesas

Laser-based manufacturing of freeform glass micro-optics through topological transformation

Glass has been the material of choice for making optical elements, in large part due to its intrinsic properties: a temperature-dependent viscosity, which enables shaping the material into a broad variety of functional and artistic glassware. Silica glass ...

EPFL2024

Searching for Strong Gravitational Lenses

Frédéric Courbin, Cameron Alexander Campbell Lemon

Strong gravitational lenses provide unique laboratories for cosmological and astrophysical investigations, but they must first be discovered - a task that can be met with significant contamination by other astrophysical objects and asterisms. Here we revie ...

Springer2024

Aggregating Spatial and Photometric Context for Photometric Stereo

David Honzátko

Photometric stereo, a computer vision technique for estimating the 3D shape of objects through images captured under varying illumination conditions, has been a topic of research for nearly four decades. In its general formulation, photometric stereo is an ...

EPFL2024

Carbon based printed electrodes for DEAs: study of pad, inkjet, and stencil printing

Yves Perriard, Yoan René Cyrille Civet, Thomas Guillaume Martinez, Stefania Maria Aliki Konstantinidi, Armando Matthieu Walter, Simon Holzer

Dielectric elastomer actuators (DEAs) have raised interest due to their remarkable capabilities in various applications, such as soft robotics, haptic feedback systems, and biomedical devices. To harness the full potential of DEAs, the choice of the electr ...

Society of Photo-Optical Instrumentation Engineers (SPIE)2024

III-N blue-emitting epi-structures with high densities of dislocations: Fundamental mechanisms for efficiency improvement and applications

Pierre Christophe Lottigier

Since the dawn of humanity, human beings seeked to light their surroundings for their well-being, security and development. The efficiency of ancient lighting devices, e.g. oil lamps or candles, was in the order of 0.03-0.04% and jumped to 0.4-0.6% with th ...

EPFL2024

A KL Divergence-Based Loss for In Vivo Ultrafast Ultrasound Image Enhancement with Deep Learning

Jean-Philippe Thiran, Roser Vinals Terres

Ultrafast ultrasound imaging, characterized by high frame rates, generates low-quality images. Convolutional neural networks (CNNs) have demonstrated great potential to enhance image quality without compromising the frame rate. However, CNNs have been most ...

2023

Printed degradable piezoelectric microsystems: From ink formulation to device fabrication and characterization

Morgan Mc Kay Monroe

As the world moves further and further into the semiconductor era, the amount of waste generated from electronics ("e-waste") is increasing rapidly and unsustainably. Of particular note, alternatives to lead-based piezoelectric materials must be establishe ...

EPFL2023

Cross-resolution Face Recognition via Identity-Preserving Network and Knowledge Distillation

Touradj Ebrahimi, Yuhang Lu

Cross-resolution face recognition has become a challenging problem for modern deep face recognition systems. It aims at matching a low-resolution probe image with high-resolution gallery images registered in a database. Existing methods mainly leverage pri ...

2023

Print-Light-Synthesis of Gold Thin Film Electrodes for Electrochemical Sensing

Horst Pick, Andreas Stephan Lesch, Emanuela Maiorano

The one-step fabrication of gold films by inkjet printing of a gold precursor ink and its photochemical reduction by exposure to UV light is presented. Inkjet printing creates on a substrate with high control micrometer-thin reaction volumes in which upon ...

Wiley2023

Nanoliter Liquid Packaging in a Bioresorbable Microsystem by Additive Manufacturing and its Application as a Controlled Drug Delivery Device

Arnaud Bertsch, Jürgen Brugger, Cristina Martin Olmos, Jongeon Park

Precise packaging of nanoliter amounts of liquid in a microsystem is important for many biomedical applications. However, existing liquid encapsulation technologies have limitations in terms of liquid waste, evaporation, trapped bubbles, and liquid degrada ...

2023

Towards learning-based denoising of light fields

Touradj Ebrahimi, Michela Testolina, Tomás Soares De Carvalho Feith

In recent years, new emerging immersive imaging modalities, e.g. light fields, have been receiving growing attention, becoming increasingly widespread over the years. Light fields are often captured through multi-camera arrays or plenoptic cameras, with th ...

2023

Ex uno plures: how to construct high-speed movies of collapsing cavitation bubbles from a single image

Mohamed Farhat, Armand Baptiste Sieber, Davide Bernardo Preso

The time-resolved visualization of the dynamics of a cavitation bubble usually requires the use of expensive high-speed cameras, which often provide a limited spatial resolution. In the present study, we propose an alternative to these high-speed imaging t ...

Springer2023

The physics of 3D printing with light

Christophe Moser

The goal of 3D printing is to realize complex 3D structures by locally adding material in small volume elements called voxels - in contrast to successively subtracting material by etching, milling or machining. This field started with optics-based proposal ...

Nature Portfolio2023

Ion-Dipole Interaction Enabling Highly Efficient CsPbI3 Perovskite Indoor Photovoltaics

Michael Graetzel, Shaik Mohammed Zakeeruddin, Di Zhang, Meng Li, Xiaoyan Wang, Haizhou Lu, Xingyu Gao, Ziyun Wang, Jie Chen

Metal halide perovskites are ideal candidates for indoor photovoltaics (IPVs) because of their easy-to-adjust bandgaps, which can be designed to cover the spectrum of any artificial light source. However, the serious non-radiative carrier recombination und ...

Wiley-V C H Verlag Gmbh2023

On combining denoising with learning-based image decoding

Touradj Ebrahimi, Michela Testolina

Noise is an intrinsic part of any sensor and is present, in various degrees, in any content that has been captured in real life environments. In imaging applications, several pre- and post-processing solutions have been proposed to cope with noise in captu ...

SPIE2022

Attribute Prediction as Multiple Instance Learning

Devis Tuia, Diego Marcos Gonzalez

Attribute-based representations help machine learning models perform tasks based on human understandable concepts, allowing a closer human-machine collaboration. However, learning attributes that accurately reflect the content of an image is not always str ...

2022

Effects of surface rigidity and metallicity on dielectric properties and ion interactions at aqueous hydrophobic interfaces

Philip Robin Loche

Using classical molecular dynamics simulations, we investigate the dielectric properties at interfaces of water with graphene, graphite, hexane, and water vapor. For graphite, we compare metallic and nonmetallic versions. At the vapor-liquid water and hexa ...

AIP Publishing2022

Low and high frequency electromagnetic forces: numerical modelling and practical applications

Marco Riccardi

The understanding and manipulation of nanoscale analytes is a central theme in nanotechnology and has been one of the main driving forces behind the development of this field as we know it today. Furthermore, such a technology has the potential to also rev ...

EPFL2022

Digital twins for post-earthquake damage assessment of free-standing buildings including damage information

Radhakrishna Achanta, Katrin Beyer, Amir Rezaie, Bryan German Pantoja Rosero

We present a pipeline for the automatic generation of digital twins of free-standing buildings for damage assessment. Our method takes multiple view images of the target building as input and processes them to produce a 3D model in levels of detail (LOD) f ...

2022

Room-temperature electrical control of polarization and emission angle in a cavity-integrated 2D pulsed LED

Andras Kis, Dmitrii Unuchek, Juan Francisco Gonzalez Marin, Fedele Tagarelli, Cheol Yeon Cheon, Zhe Sun

Devices based on two-dimensional (2D) semiconductors hold promise for the realization of compact and versatile on-chip interconnects between electrical and optical signals. Although light emitting diodes (LEDs) are fundamental building blocks for integrate ...

Nature Research2022