Publications associées à Lampe torche

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

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

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

Tailoring Triple-Anion Perovskite Material for Indoor Light Harvesting with Restrained Halide Segregation and Record High Efficiency Beyond 36%

Hong Zhang, Zhiwen Zhou, Fangzhou Liu

Indoor photovoltaics are promising to enable self-powered electronic devices for the Internet of Things. Here, reported is a triple-anion CH3NH3PbI2-xBrClx perovskite film, of which the bandgap is specially designed for indoor light harvesting to achieve a ...

2019

Long-life plastic optical fiber probes for scanning near-field optical microscope

Giovanni Dietler, Serguei Sekatski, Anton Smirnov, Ekaterina Rostova

Nowadays, sharpened glass fiber - made probes attached to a quartz tuning fork (TF) and exploiting the shear force - based feedback are by far the most popular in the field of SNOM. These probes are expensive, very fragile and their fabrication is difficul ...

SPIE-INT SOC OPTICAL ENGINEERING2018

Ultrafast spectroscopy of wide bandgap semiconductor nanostructures

Mehran Shahmohammadi

Group III-nitrides have been considered a promising choice for the realization of optoelectronic devices since 1970. Since the first demonstration of the high-brightness blue light-emitting diodes (LEDs) by Shuji Nakamura and coworkers, the fabrication of ...

EPFL2015

Instrumental correction of the uneven PMT aging effect on the calibration constant of a water vapor Raman lidar

Valentin Simeonov, Bertrand Calpini, Salomon Fastig

The water vapor profile derived from Raman lidar measurements is obtained by taking the ratio of water vapor and nitrogen Raman-shifted signals. The proportionality factor that converts the signal ratio to water vapor/air mixing ratio is referred to as lid ...

Spie-Int Soc Optical Engineering2014

Class AAA LED-Based Solar Simulator for Steady-State Measurements and Light Soaking

Christophe Ballif, Franz-Josef Haug, Matthieu Despeisse, Michael Elias Stückelberger, Yannick Samuel Riesen, Maximilien Joseph Marie Bonnet-Eymard, Brice Perruche

Recent improvements in light-emitting diode (LED) technology has allowed for the use of LEDs for solar simulators with excellent characteristics. In this paper, we present a solar simulator prototype fully based on LEDs. Our prototype has been designed spe ...

Ieee-Inst Electrical Electronics Engineers Inc2014

A micro particle shadow velocimetry (mu PSV) technique to measure flows in microchannels

John Richard Thome, Sepideh Khodaparast, Giulia Tagliabue, Navid Borhani

A micro particle shadow velocimetry (mu PSV) system based on back-lit illumination and forward scatter observation of light from non-fluorescent particles has been developed. Relatively high luminous efficiencies and particle image contrasts were achieved ...

Springer-Verlag2013

Contactless deflection sensor for soft robots

Dario Floreano, Ramon Pericet Camara, Michal Karol Dobrzynski

In the emerging field of soft robotics, there is an interest in developing new kinds of sensors whose characteristics do not affect the intrinsic compliance of soft robot components. Additionally, non-invasive shape and deflection sensors may provoke impro ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2011

Advanced Window and Lighting Technologies in net Zero Energy Buildings

Jean-Louis Scartezzini

Light has an important visual and non-visual impact on humans. Most of our information exchange, especially within office working spaces, occurs through it, our circadian rhythms are directly influenced by its presence. On the other hand, artificial lighti ...

2011