Concept

LED street light

Publications associées (82)

Ion-Dipole Interaction Enabling Highly Efficient CsPbI3 Perovskite Indoor Photovoltaics

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

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

Characterization of two electronic subsystems in cuprates through optical conductivity

Ana Akrap, Neven Barisic

Understanding the physical properties of unconventional superconductors as well as of other correlated materials presents a formidable challenge. Their unusual evolution with doping, frequency, and temperature has frequently led to non-Fermi-liquid (non-FL ...

2023

Optical Diffraction Tomography Using Nearly In-Line Holography with a Broadband LED Source

Demetri Psaltis, Abhijit Roy, Ahmed Ayoub

We present optical tomography methods for a 3D refractive index reconstruction of weakly scattering objects using LED light sources. We are able to record holograms by minimizing the optical path difference between the signal and reference beams while sepa ...

MDPI2022

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

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

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

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 ...

2022

Defects in III-N LEDs: experimental identification and impact on electro-optical characteristics

Nicolas Grandjean, Jean-François Carlin, Mauro Mosca, Camille Haller

III-N light-emitting-diodes (LEDs) are subject of intense investigations, thanks to their high efficiency and great reliability. The quality of the semiconductor material has a significant impact on the electro-optical performance of LEDs: for this reason, ...

SPIE-INT SOC OPTICAL ENGINEERING2022

Visual comfort without borders: Extending daylight glare prediction to dim daylit environments

Geraldine Cai Ting Quek

Avoiding discomfort glare is one of the critical aspects of maintaining visual comfort, which significantly influences occupants' overall satisfaction with their indoor environment. Discomfort glare prediction models have been developed for various lightin ...

EPFL2022

Deep defects in InGaN LEDs: modeling the impact on the electrical characteristics

Nicolas Grandjean, Jean-François Carlin, Camille Haller

Deep defects have a fundamental role in determining the electro-optical characteristics and in the efficiency of InGaN light-emitting diodes (LEDs). However, modeling their effect on the electrical characteristics of the LED is not straightforward. In this ...

SPIE-INT SOC OPTICAL ENGINEERING2022

Effects of illuminance intensity on the green channel of remote photoplethysmography (rPPG) signals

Ata Jedari Golparvar

Point-of-care remote photoplethysmography (rPPG) devices that utilize low-cost RGB cameras have drawn considerable attention due to their convenience in contactless and non-invasive vital signs monitoring. In rPPG, sufficient lighting conditions are essent ...

SPRINGER2022

Spatial evaluation of potential saturation and contrast effects of discomfort glare in an open-plan office

Marilyne Andersen, Jan Wienold, Stephen William Wasilewski, Geraldine Cai Ting Quek

This paper analyzes the relative distribution of annual saturation and contrast effects of discomfort glare in a deep open-plan office. A previous comparative study has shown that while hybrid glare metrics were found to predict glare well in most scenario ...

2021

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