Publications related to Ommatidium

Photovoltaic retinal prosthesis restores high-resolution responses to single-pixel stimulation in blind retinas

Diego Ghezzi, Naïg Aurelia Ludmilla Chenais, Marta Jole Ildelfonsa Airaghi Leccardi

Retinal prostheses hold the promise of restoring vision in totally blind people. However, a decade of clinical trials highlighted quantitative limitations hampering the possibility of reaching this goal. A key challenge in retinal stimulation is to indepen ...

2021

Photovoltaic stimulation of retinal microcircuit for vision restoration

Naïg Aurelia Ludmilla Chenais

Sight restoration through retinal prostheses was still a mere dream a century ago. Current challenges are even greater: providing a quantitatively and qualitatively useful artificial vision to late blind patients. Existing approaches all face engineering a ...

EPFL2021

Long-lasting feature integration

Leila Drissi Daoudi - Kleinbauer

In the classic model of vision, processing is local, feedforward and hierarchical. The first stages of the visual system are retinotopic, i.e., neighboring points in the outside world are mapped onto neighboring photoreceptors of the retina and this is pre ...

EPFL2020

Gene Editing Preserves Visual Functions in a Mouse Model of Retinal Degeneration

Diego Ghezzi, Naïg Aurelia Ludmilla Chenais, Paola Vagni, Tommaso Marchetti

Inherited retinal dystrophies (IRDs) are a large and heterogeneous group of degenerative diseases caused by mutations in various genes. Given the favorable anatomical and immunological characteristics of the eye, gene therapy holds great potential for thei ...

2019

Beyond Bouma's window: How to explain global aspects of crowding?

Michael Herzog, Gregory Francis, Adrien Christophe Doerig, Aaron Michael Clarke, Alban Bornet

In crowding, perception of an object deteriorates in the presence of nearby elements. Although crowding is a ubiquitous phenomenon, since elements are rarely seen in isolation, to date there exists no consensus on how to model it. Previous experiments show ...

2019

Insect-Inspired Visual Perception for Flight Control and Collision Avoidance

Julien Jean Denis Nicolas Lecoeur

Flying robots are increasingly used for tasks such as aerial mapping, fast exploration, video footage and monitoring of buildings. Autonomous flight at low altitude in cluttered and unknown environments is an active research topic because it poses challen ...

EPFL2019

Multilevel regulation of the glass locus during Drosophila eye development

Bart Deplancke, Michael Vincent Frochaux, Abhishek Kumar Mishra

Development of eye tissue is initiated by a conserved set of transcription factors termed retinal determination network (RDN). In the fruit fly Drosophila melanogaster, the zinc-finger transcription factor Glass acts directly downstream of the RDN to contr ...

2019

From retinotopic processing to nonretinotopic representation

Marc Michael Lauffs

Encoding of visual information in the brain is retinotopic: Neighboring points in the visual field are mapped onto neighboring photoreceptors in the retina, and these neighborhood relations are maintained in the early stages of cortical processing. However ...

EPFL2017

Orientation invariant and non-parametric Axon Diameter Distribution mapping using PGSE and regularized discrete linear modeling

Jean-Philippe Thiran, David Paul Roger Romascano, Alessandro Daducci, Muhamed Barakovic, Anna Auria Rasclosa, Tim Bjørn Dyrby

Axon Diameter Distributions (ADDs) change during brain development and are altered in several brain pathologies. Mapping ADDs non-invasively using dMRI could provide a useful biomarker, but existing methods are either parametric, orientation dependent, sur ...

2017

An artificial elementary eye with optic flow detection and compositional properties

Dario Floreano, Michal Karol Dobrzynski, Ramon Pericet Camara

We describe a 2 mg artificial elementary eye whose structure and functionality is inspired by compound eye ommatidia. Its optical sensitivity and electronic architecture are sufficient to generate the required signals for the measurement of local optic flo ...

2015

Curved artificial compound-eyes for autonomous navigation

Ramon Pericet Camara

Natural compound-eyes consist of a large number of ommatidia that are arranged on curved surfaces and thus are able to detect signals from a wide field of view. We present an integrated artificial compound-eye sensor system with enhanced field of view of 1 ...

SPIE-INT SOC OPTICAL ENGINEERING2014

FREAK: Fast Retina Keypoint

Pierre Vandergheynst, Alexandre Massoud Alahi, Raphaël Ortiz

A large number of vision applications rely on matching keypoints across images. The last decade featured an arms-race towards faster and more robust keypoints and association algorithms: Scale Invariant Feature Transform (SIFT), Speed-up Robust Feature (SU ...

Ieee2012

A (fascinating) litmus test for human retino- vs. non-retinotopic processing

Michael Herzog, Thomas Otto, Marco Boi

In human vision, the optics of the eye map neighboring points of the environment onto neighboring photoreceptors in the retina. This retinotopic encoding principle is preserved in the early visual areas. Under normal viewing conditions, due to the motion o ...

Association for Research in Vision and Ophthalmology2009

Identification of the minimal promoter region of the mouse NKX5-3, a transcription factor implicated in eye development

Early ocular development is controlled by a complex network of transcription factors, cell cycle regulators, and diffusible signalling molecules. Together, these molecules regulate cell proliferation and apoptosis, and specify retinal fate. NKX5-3 is a hom ...

2008