Publications related to Photographic filter

Optimal digital filter selection for remote photoplethysmography (rPPG) signal conditioning

Remote photoplethysmography (rPPG) using camera-based imaging has shown excellent potential recently in vital signs monitoring due to its contactless nature. However, the optimum filter selection for pre-processing rPPG data in signal conditioning is still ...

IOP Publishing Ltd2023

Biomaterial devices on Arecanut palm leaf for microwave applications

Anja Skrivervik, Sujith Raman

This paper presents an investigation on the possibility of arecanut palm leaf as a biomaterial substrate for various microwave devices such as transmission lines, antenna, filter and a radio frequency identification device (RFID). The dielectric properties ...

IEEE2023

Fully reconfigurable MEMS-based second-order coupled-resonator optical waveguide (CROW) with ultra-low tuning energy

Niels Quack, Alain Yuji Takabayashi

Integrated microring resonators are well suited for wavelength-filtering applications in optical signal processing, and cascaded microring resonators allow flexible filter design in coupledresonator optical waveguide (CROW) configurations. However, the imp ...

Optica Publishing Group2023

Ultra-Small Bent Meta-Waveguide Filters

Romain Christophe Rémy Fleury, Maliheh Khatibi Moghaddam

This paper demonstrates the capability of locally resonant metamaterials (LRMs) for creating compact metallic waveguide E- and H-bends, which are simultaneously working as bandpass filters. For creating these bent meta-filters, we use composite pin-pipe wa ...

IEEE2022

Study of Thin Film LiNbO3 Laterally Excited Bulk Acoustic Resonators

Luis Guillermo Villanueva Torrijo, Soumya Yandrapalli, Hüseyin Baris Atakan, Victor Plessky

This work presents an in-depth study of simulation and measurement results of laterally excited shear bulk acoustic resonators (XBAR) in Lithium Niobate, at 5 GHz with high electromechanical coupling factor (k(t)(2)) as high as 25%, and with impedances at ...

Institute of Electrical and Electronics Engineers2022

Towards a N77 Electroacoustic Filter Using Thin Films of Crystalline Y-cut Lithium Niobate

Luis Guillermo Villanueva Torrijo, Soumya Yandrapalli, Victor Plessky

This paper presents the use of a novel type of resonators made of a thin membrane of Y-cut Lithium Niobate that has an array of interdigitated electrodes on the top, and a floating metal on the bottom. Each electrode gives rise to a quasi-independent reson ...

IEEE2021

Polyamide Nanofiber-Based Air Filters for Transparent Face Masks

Thierry Pelet, René M. Rossi

Transparent face masks are the ultimate solution for improving communication during pandemic times while at the same time slowing the spread of pathogens. Here, we demonstrate an easily scalable process consisting of directly electrospinning polyamide nano ...

AMER CHEMICAL SOC2021

Tomographic reconstruction of the runaway distribution function in TCV using multispectral synchrotron images

Basil Duval, Joan Decker, Umar Sheikh, Artur Perek, Gergely Papp

Synchrotron radiation observed in a quiescent Tokamak a Configuration Variable (TCV) runaway discharge is studied using filtered camera images targeting three distinct wavelength intervals. Through the tomographic simultaneous algebraic reconstruction tech ...

IOP Publishing Ltd2021

Filter quotients and non-presentable (∞,1)-toposes

Nima Rasekh

We define filter quotients of -categories and prove that filter quotients preserve the structure of an elementary -topos and in particular lift the filter quotient of the underlying elementary topos. We then specialize to the case of filter products of -ca ...

2021

Ultra-Compact Ka-band Metamaterial Waveguide Filters, Fabricated by Lost-Wax Casting

Romain Christophe Rémy Fleury, Maliheh Khatibi Moghaddam

This paper proposes a novel technique for the design of miniaturized Ka-band filters based on locally resonant metamaterials (LRMs), which are fabricated monolithically using lost wax casting. We implement ultra-small metamaterial filters by exploiting a n ...

IEEE2021

Figlearn: Filter And Graph Learning Using Optimal Transport

Pascal Frossard, Mireille El Gheche, Matthias Minder, Zahra Farsijani

In many applications, a dataset can be considered as a set of observed signals that live on an unknown underlying graph structure. Some of these signals may be seen as white noise that has been filtered on the graph topology by a graph filter. Hence, the k ...

IEEE2021

FABRICATION AND ANALYSIS OF THIN FILM LITHUM NIOBATE RESONATORS FOR 5GHz FREQUENCY AND LARGE k(t)(2) APPLICATIONS

Luis Guillermo Villanueva Torrijo, Seniz Esra Küçük, Soumya Yandrapalli, Victor Plessky

This work presents the fabrication and analysis of suspended thin film Lithium Niobate resonators. The yield of the new fabrication process presented below is >90% showing devices with high k(t)(2) of 28% resonators at 5GHz, making them suitable for high f ...

IEEE2021

Machine learning based detection of digital documents maliciously recaptured from displays

Touradj Ebrahimi, Evgeniy Upenik, Saleh Gholam Zadeh

We used to say “seeing is believing": this is no longer true. The digitization is changing all aspects of life and business. One of the more noticeable impacts is in how business documents are being authored, exchanged and processed. Many documents such as ...

2020

Image-Based Acquisition and Modeling of Polarimetric Reflectance

Wenzel Alban Jakob, Tizian Lucien Zeltner, Xin Tong

Realistic modeling of the bidirectional reflectance distribution function (BRDF) of scene objects is a vital prerequisite for any type of physically based rendering. In the last decades, the availability of databases containing real-world material measurem ...

ASSOC COMPUTING MACHINERY2020

Learning Temporary Block-Based Bidirectional Incongruity-Aware Correlation Filters for Efficient UAV Object Tracking

Yujie He

In the field of UAV object tracking, correlation filter based approaches have received lots of attention due to their computational efficiency. The methods learn filters by the ridge regression and generate response maps to distinguish the specified target ...

2020

A Subwavelength Microwave Bandpass Filter Based on a Chiral Waveguide

Romain Christophe Rémy Fleury, Maliheh Khatibi Moghaddam

Wave manipulation at a subwavelength scale has recently attracted significant interest, especially for low-frequency wave propagation, from acoustic to microwave devices. Recently, a few methods achieving subwavelength routing using locally resonant metama ...

IEEE Xplore2020

On design strategies for binary dielectric metasurfaces based on the Fourier modal method

Kévin Müller

Binary dielectric metasurfaces are arrays of sub-wavelength structures that act as a thin layer of artificial material. They are generally lossless and relatively simple to fabricate since only a single structuring step is required. By carefully designing ...

EPFL2020

Embedded Polarizing Filters to Separate Diffuse and Specular Reflection

Laurent Valentin Jospin, Adam James Scholefield, Gilles Baechler

Polarizing filters provide a powerful way to separate diffuse and specular reflection; however, traditional methods rely on several captures and require proper alignment of the filters. Recently, camera manufacturers have proposed to embed polarizing micro ...

SPRINGER INTERNATIONAL PUBLISHING AG2019

Distributed forward stimulated Brillouin scattering measurement using broadband BOTDR

Luc Thévenaz, Simon Adrien Zaslawski, Zhisheng Yang, Sheng Wang

Brillouin optical time-domain reflectometry is used to perform distributed forward stimulated Brillouin scattering (FSBS) measurements. This configuration suppresses the need for an additional frequency scanning to evaluate the local Brillouin peak gain wh ...

SPIE2019

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