Publications related to Spectral power distribution

Dynamic control of high-voltage actuator arrays by light-pattern projection on photoconductive switches

Herbert Shea, Amir Firouzeh, Edouard Franck Vincent Gustave Leroy, Vesna Bacheva, Aiste Balciunaite

The ability to control high-voltage actuator arrays relies, to date, on expensive microelectronic processes or on individual wiring of each actuator to a single off-chip high-voltage switch. Here we present an alternative approach that uses on-chip photoco ...

SPRINGERNATURE2023

Polarization-Controlled Chromo-Encryption

Olivier Martin, Hsiang-Chu Wang

The response of simple plasmonic nanorods to polarized illumination is studied in detail. Depending on the orientation of that polarization with respect to the symmetry axes of the nanostructure, a chiral response can occur, which can be analyzed through a ...

WILEY-V C H VERLAG GMBH2023

Comparison between CIE 2° and 10° field photopic luminosity functions V(λ) for calculating daylight discomfort glare metrics

Marilyne Andersen, Jan Wienold, Sneha Jain

The spectral sensitivity of the average human eye in photopic conditions is represented by the photopic luminosity function V (λ). The CIE has established the photopic luminosity functions for the 2o and 10o visual fields for a standard observer applicable ...

2022

Validation of Spectral Simulation Tools for the Prediction of Indoor Daylight Exposure

Marilyne Andersen, Clotilde Marie A Pierson

A growing area of research focuses on the relationship between ocular light exposure and the non-visual responses. In order to accelerate research on this topic and improve building design, reliable spectral simulation tools are needed. This study aims at ...

2021

Multichromatic calibration method and device

Dragos Constantin

A Multichromatic Calibration (MC) method of at least a spectral sensor which is one of a list comprising at least a spectrometer, a multispectral sensor, a hyperspectral sensor, a spectral camera, a color camera. The method comprises a. generating a plural ...

2019

Automated Daylighting Control System based on Sky Luminance Monitoring and Lighting Computing

Yujie Wu

Sufficient daylight exposure contributes to occupants' productivity and health in buildings. However, excessive daylight ingress induces discomfort glare and increases the cooling load in warm seasons. The performance of manual shading systems is limited b ...

EPFL2019

Self-Similar Multiresonant Nanoantenna Arrays for Sensing from Near- to Mid-Infrared

Hatice Altug, Andreas Tittl, Daniel Rodrigo Lopez, Aurélian Michel John-Herpin, Odeta Limaj

Tailoring nanoscale light concentration and electromagnetic near-field enhancement over a broad spectral range is crucial for many photonics applications such as infrared spectroscopy, photodetection, and light harvesting. So far, broadband light enhanceme ...

2018

Indoor Light Enhanced Photocatalytic Ultra-Thin Films on Flexible Non-Heat Resistant Substrates Reducing Bacterial Infection Risks

Sami Rtimi

Photocatalytic antibacterial sol-gel coated substrates have been reported to kill bacteria under light or in the dark. These coatings showed non-uniform distribution, poor adhesion to the substrate and short effective lifetime as antibacterial surfaces. Th ...

Mdpi Ag2017

Glare Caused By Contrast Between Task And Immediate Surround: An Evaluation Of Luminance Distribution In The Field Of View

Marilyne Andersen, Jan Wienold, Peter Hansen, Mandana Sarey Khanie

Luminance ratios have historically been used to assess glare. Using data from a previous experiment, this exploratory study investigates the relationship between luminance variations in the field of view (FOV), measured as luminance ratios, and glare sensa ...

Cie Central Bureau2016

Demultiplexing Visible and Near-Infrared Information in Single- Sensor Multispectral Imaging

Sabine Süsstrunk, Zahra Sadeghipoor Kermani, Jean-Baptiste Thomas

In this paper, we study a single-sensor imaging system that uses a multispectral filter array to spectrally sample the scene. Our system captures information in both visible and near-infrared bands of the electromagnetic spectrum. Due to manufacturing limi ...

2016

A New Anti-Counterfeiting Feature Relying on Invisible Luminescent Full Color Images Printed with Lanthanide-Based Inks

Roger Hersch, Jacques-Edouard Moser, Anne-Sophie Chauvin, Julien Alexandre Andres

Europium and terbium trisdipicolinate complexes are inkjet printed onto paper with commercially available desktop inkjet printers. Together with a commercial blue luminescent ink, the red-emitting luminescent ink containing europium and the green-emitting ...

Wiley-Blackwell2014

Near-Infrared Guided Color Image Dehazing

Sabine Süsstrunk, Chen Feng

Near-infrared (NIR) light has stronger penetration capability than visible light due to its long wavelength, thus being less scattered by particles in the air. This makes it desirable for image dehazing to unveil details of distant objects in landscape pho ...

2013

The Impact of Light Including Non-Image Forming Effects on Visual Comfort

Apiparn Borisuit

Visual comfort at workplaces has often been considered in terms of discomfort glare, luminance distribution and task visibility. Besides visual effects, the lighting environment has also impact on human physiology and behaviour. These effects of light are ...

EPFL2013

From Luminescent Lanthanide Complexes to Color Reproduction and Optical Document Security with Invisible Luminescent Inks

Julien Alexandre Andres

The present thesis deals with luminescent compounds based on lanthanide complexes that are suitable for color reproduction and optical document security with invisible luminescent inks. This thesis is divided in two distinct fields: chemistry, which produc ...

EPFL2012

Constrained Acquisition of Ink Spreading Curves From Printed Color Images

Roger Hersch, Thomas Bugnon

Today's spectral reflection prediction models are able to predict the reflection spectra of printed color images with an accuracy as high as the reproduction variability allows. However, to calibrate such models, special uniform calibration patches need to ...

2011

Endoscopic Fluorescence Imaging : Spectral Optimization and in vivo Characterization of Positive Sites by Magnifying Vascular Imaging

Blaise Lovisa

Since several decades, the physicians are able to access hollow organs with endoscopic methods, which serve both as diagnostic and surgical means in a wide range of disciplines of the modern medicine (e.g. urology, pneumology, gastroenterology). Unfortunat ...

EPFL2010

Exploiting redundancy in color images

Joanna Marguier

The colors in a digital image do not only depend on the scene's reflectances, but also on the lighting conditions and on the characteristics of the imaging device. It is often necessary to separate the influence of these three elements, in particular to se ...

EPFL2010

Yule-Nielsen approach for predicting the spectral transmittance of halftone prints

Roger Hersch, Mathieu Hébert

The transmittance spectrum of halftone prints on paper is predicted thanks to a model inspired by the Yule-Nielsen modified spectral Neugebauer model used for reflectance predictions. This model is well adapted for semi-opaque printing supports and applica ...

IS&T2009

Calibrating the Yule-Nielsen modified spectral Neugebauer model with ink spreading curves derived from digitized RGB calibration patch images

Roger Hersch, Adish Kumar Singla, Nikhil Garg

The Yule-Nielsen modified spectral Neugebauer model (YNSN) enhanced for accounting for ink spreading in the different ink superposition conditions requires a photospectrometer to measure the reflectances of halftone calibration patches in order to compute ...

2008

A Master-Slave Approach for Object Detection and Matching with Fixed and Mobile Cameras

Michel Bierlaire, Murat Kunt, Alexandre Massoud Alahi

Typical object detection algorithms on mobile cameras suffer from the lack of a-priori knowledge on the object to be detected. The variability in the shape, pose, color distribution, and behavior affect the robustness of the detection process. In general, ...

2008