Publications associées à Zoom

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

The impact of human expert visual inspection on the discovery of strong gravitational lenses

Frédéric Courbin, Benjamin Yvan Alexandre Clement, Eric Gérard Guy Paic, Hung-Hsu Chan, Martin Raoul Robert Millon, Karina Alexandra Rojas Olate, Rémy Elie Joseph, Elodie Marie Charlène Savary, Yue Pan

We investigate the ability of human 'expert' classifiers to identify strong gravitational lens candidates in Dark Energy Survey like imaging. We recruited a total of 55 people that completed more than 25 per cent of the project. During the classification t ...

OXFORD UNIV PRESS2023

Media Coverage of 3D Visual Tools Used in Urban Participatory Planning

Jens Ingensand, Thibaud Nicolas Chassin

The opportunities provided by adopting digitally-generated visual tools in urban participatory planning are compelling. These visual tools can promote interactions between authorities and citizens and among citizens. However, the urban participatory practi ...

IGI GLOBAL2023

Gravitationally lensed quasars in Gaia - IV. 150 new lenses, quasar pairs, and projected quasars

Frédéric Courbin, Aymeric Alexandre Galan, Cameron Alexander Campbell Lemon, Adriano Agnello

We report the spectroscopic follow-up of 175 lensed quasar candidates selected using Gaia Data Release 2 observations following Paper III of this series. Systems include 86 confirmed lensed quasars and a further 17 likely lensed quasars based on imaging an ...

OXFORD UNIV PRESS2023

TOCOSMO VIII. A key test of systematics in the hierarchical method of time-delay cosmography

Frédéric Courbin

The largest source of systematic errors in the time-delay cosmography method likely arises from the lens model mass distribution, where an inaccurate choice of model could in principle bias the value of H-0. A Bayesian hierarchical framework has been propo ...

EDP SCIENCES S A2022

Using wavelets to capture deviations from smoothness in galaxy-scale strong lenses

Frédéric Courbin, Aymeric Alexandre Galan, Georgios Vernardos, Austin Chandler Peel

Modeling the mass distribution of galaxy-scale strong gravitational lenses is a task of increasing difficulty. The high-resolution and depth of imaging data now available render simple analytical forms ineffective at capturing lens structures spanning a la ...

EDP SCIENCES S A2022

Beyond Cameras: Real-Time High-Resolution 3D and Panoramic MultiView Vision Systems with Their Applications

Bilal Demir

The cameras are invented by imitating the human visual system to capture the scene. The camera technologies have been substantially advanced in recent years. 108 MP resolution with 100x hybrid zoom has become standard features for smartphone flagships. In ...

EPFL2020

Camera Calibration Models and Methods for Corridor Mapping with UAVs

Jan Skaloud, Davide Antonio Cucci, Emmanuel Pierre Quentin Clédat

Camera calibration refers to the modeling of the relationship between the coordinates of object points and their projections on the image plane. This is usually done by parametric models that describe the physical properties of the lens systems and camera ...

2020

Lens aberration compensation in interference microscopy

Yves Bellouard, Jakub Drs

Emergence of products that feature functional surfaces with complex geometries, such as freeform optics in consumer electronics and augmented reality and virtual reality, requires high-accuracy non-contact surface measurement. However, large discrepancies ...

2020

Closed-Form Solution to Disambiguate Defocus Blur in Single-Perspective Images

Sabine Süsstrunk, Majed El Helou, Marjan Shahpaski

Depth-from-defocus techniques suffer an ambiguity problem where depth planes on opposite sides of the focal plane have identical defocus. We solve the ambiguity by relying on the wavelength-dependent relationship between defocus and depth. We conduct a rob ...

2019

Improvements on the uniformity of large-area microlens arrays in Fused Silica

Toralf Scharf, Wilfried Noell, Raoul Kirner, Jeremy Béguelin

The uniformity of large microlens arrays in Fused Silica is governed by the production process. It comprises photolithographic patterning of a spin-coated layer of photoresist on a 200mm wafer with a molten resist reflow process and subsequent dry etching. ...

OPTICAL SOC AMER2019

Solving the Depth Ambiguity in Single-Perspective Images

Sabine Süsstrunk, Majed El Helou, Marjan Shahpaski

Scene depth estimation is gaining in importance as more and more AR/VR and robot vision applications are developed. Conventional depth-from-defocus techniques can passively provide depth maps from a single image. This is especially advantageous for moving ...

2019

Sky Monitoring System

Jean-Louis Scartezzini, Jérôme Henri Kämpf, Yujie Wu

In a sky monitoring system (S), comprising an image sensor (1), a wide angle lens (16), a microprocessor (3), and a memory unit (11, 18), wherein the sky monitoring system (S) is configured to take pictures of a sky scene, wherein the sky monitoring system ...

2018

AAM: An Assessment Metric of Axial Chromatic Aberration

Sabine Süsstrunk, Majed El Helou, Frederike Dümbgen

Knowledge of lens specifications is important to identify the best lens for a given capture scenario and application. Lens manufacturers provide many specifications in their data sheets, and multiple initiatives for testing and comparing different lenses c ...

2018

Survey of Gravitationally Lensed Objects in HSC Imaging (SuGOHI). II. Environments and Line-of-Sight Structure of Strong Gravitational Lens Galaxies to z similar to 0.8

Hung-Hsu Chan

We investigate the local and line-of-sight (LOS) overdensities of strong gravitational lens galaxies using wide-area multiband imaging from the Hyper Suprime-Cam Subaru Strategic Program. We present 41. new definite or probable lens candidates discovered i ...

2018

Carbon Nanotube Array Based Binary Gabor Zone Plate Lenses

Sunan Deng, Chaohui Li

Diffractive zone plates have a wide range of applications from focusing x-ray to extreme UV radiation. The Gabor zone plate, which suppresses the higher-order foci to a pair of conjugate foci, is an attractive alternative to the conventional Fresnel zone p ...

Nature Research2017

An embedded system for quasi real-time lighting computation based on sky monitoring

Jean-Louis Scartezzini, Jérôme Henri Kämpf, Yujie Wu

Lighting simulation plays a significant role in the architectural design and evaluation of performance parameters of buildings. The general method of assuming a virtual sky in lighting simulation may lead to mismatch with the real situation, which conventi ...

2017

Scaling effect and its impact on wavelength-scale microlenses

Hans Peter Herzig, Toralf Scharf, Myun Sik Kim

We revisit the scaling laws in micro-optical systems to highlight new phenomena arising beyond a conventional optical regime, especially when the size of the system approaches to the operational wavelength. Our goal is to visualize the impact of the scalin ...

Spie-Int Soc Optical Engineering2017

Real-Time Computational Gigapixel Multi-Camera Systems

Vladan Popovic

The standard cameras are designed to truthfully mimic the human eye and the visual system. In recent years, commercially available cameras are becoming more complex, and offer higher image resolutions than ever before. However, the quality of conventional ...

EPFL2016

Ultrafast All-Polymer Electrically Tunable Silicone Lenses

Herbert Shea, Samuel Rosset, Luc Maffli, Michele Ghilardi

Dielectric elastomer actuators (DEA) are smart lightweight flexible materials integrating actuation, sensing, and structural functions. The field of DEAs has been progressing rapidly, with actuation strains of over 300% reported, and many application conce ...

Wiley-Blackwell2015