Publications associées à Oculaire

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

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

Almost surely constrained convex optimization

Volkan Cevher, Ahmet Alacaoglu

We propose a stochastic gradient framework for solving stochastic composite convex optimization problems with (possibly) infinite number of linear inclusion constraints that need to be satisfied almost surely. We use smoothing and homotopy techniques to ha ...

2019

Geometric calibration of Colour and Stereo Surface Imaging System of ESA's Trace Gas Orbiter

François Fleuret, Anton Ivanov, Stepan Tulyakov, Nicolas Thomas, Thomas Weigel

There are many geometric calibration methods for "standard" cameras. These methods, however, cannot be used for the calibration of telescopes with large focal lengths and complex off-axis optics. Moreover, specialized calibration methods for the telescopes ...

Elsevier2018

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

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

Super-Resolution Imaging of a Dielectric Microsphere Is Governed by the Waist of Its Photonic Nanojet

Martinus Gijs, Raphaël Etienne Jean Trouillon, Hui Yang, Gergely Huszka

Dielectric microspheres with appropriate refractive index can image objects with super-resolution, that is, with a precision well beyond the classical diffraction limit. A microsphere is also known to generate upon illumination a photonic nanojet, which is ...

American Chemical Society2016

Refraction limit of miniaturized optical systems: a ball-lens example

Hans Peter Herzig, Roland Andreas Bitterli, Toralf Scharf, Wilfried Noell, Myun Sik Kim

We study experimentally and theoretically the electromagnetic field in amplitude and phase behind ball-lenses across a wide range of diameters, ranging from a millimeter scale down to a micrometer. Based on the observation, we study the transition between ...

Optical Society of America2016

Organic-inorganic-hybrid-polymer microlens arrays with tailored optical characteristics and multi-focal properties

Jürgen Brugger, Victor Javier Cadarso Busto, Loïc Jacot-Descombes

Plano-convex microlens arrays of organic-inorganic polymers with tailored optical properties are presented. The fine-tuning of each microlens within an array is achieved by confining inkjet printed drops of the polymeric ink onto pre-patterned substrates. ...

Optical Society of America2015

Curved Holographic Combiner for Color Head Worn Display

Jürgen Brugger, Christophe Moser, Eric Tremblay, Victor Javier Cadarso Busto, Jonas Grossenbacher, Arnaud Mader, Seyedpayam Vahdati

A volume hologram recorded with a lens array is proposed as a color transflective screen for Head Worn Display (HWD) systems. Design, fabrication as well as proof of concept are reported. Light from a single MEMS-based projector is efficiently diffracted t ...

Ieee-Inst Electrical Electronics Engineers Inc2014