Lesser-known piezoelectric and pyroelectric applications of electroactive polymers

2005 ◽  
Vol 889 ◽  
Author(s):  
Sidney B. Lang ◽  
Supasarote Muensit
Keyword(s):  
Infrared Detectors ◽  
Polyvinylidene Fluoride ◽  
Piezoelectric Effect ◽  
Ferroelectric Ceramics ◽  
Porous Polymers ◽  
Large Area ◽  
Infrared Sensors ◽  
Pyroelectric Effect ◽  
Ultrasonic Devices ◽  
Property Measurement

ABSTRACTThe piezoelectric effect was first observed in polyvinylidene fluoride polymer (PVDF) in 1969 and the pyroelectric effect was found several years later. A number of additional ferroelectric polymers have been discovered since that time including the copolymer PVDF with trifluoroethylene (P(VDF-TrFE)), and the odd-numbered nylons. A large number of applications of piezoelectricity and pyroelectricity have been developed. The magnitudes of the effects in polymers are much lower than those of ferroelectric ceramics (an exception is the piezoelectric effect in porous polymers). However, other factors make these very desirable materials for applications. The polymers have low permittivities, low acoustic impedances and low thermal conductivities. They are available in large area sheets and they are flexible and relatively low in cost. Major applications include microphones and loudspeakers, ultrasonic devices, SAW transducers, actuators, infrared detectors and many others. This review will describe some of the lesser-known applications of these materials in the fields of tactile devices, energy conversion, porous polymers, property measurement, pyroelectric infrared sensors, shock sensors and space science.

Longitudinal piezoelectric effect and hydrostatic response in novel laminar composites based on ferroelectric ceramics

2019 ◽  
Vol 45 (17) ◽  
pp. 22241-22248 ◽  
Author(s):  
A.A. Nesterov ◽  
V.Yu. Topolov ◽  
M.I. Tolstunov ◽  
A.N. Isaeva
Keyword(s):  
Piezoelectric Effect ◽  
Ferroelectric Ceramics ◽  
Laminar Composites

Experimental Investigation on the Use of Photostrictive Optical Actuator for MEMS Devices and Verification With the FEA Modeling Results

2011 ◽  
Author(s):  
Mosfequr Rahman ◽  
Masud Nawaz ◽  
John E. Jackson
Keyword(s):  
Thin Film ◽  
Lead Zirconate Titanate ◽  
Piezoelectric Effect ◽  
Photovoltaic Effect ◽  
Research Work ◽  
High Energy ◽  
Ferroelectric Ceramics ◽  
Control Signals ◽  
Fea Modeling ◽  
Converse Piezoelectric Effect

Photostrictive materials are lanthanum-modified lead zirconate titanate (Pb, La)(Zr, Ti) O3 ceramics doped with WO3, called PLZT, exhibit large photostriction under uniform illumination of high-energy light. Photostrictive materials are ferrodielectric ceramics that have a photostrictive effect. Photostriction arises from a superposition of the photovoltaic effect, i.e. the generation of large voltage from the irradiation of light, and the converse-piezoelectric effect, i.e. expansion or contraction under the voltage applied. When non-centrosymmetric materials, such as ferroelectric single crystals or polarized ferroelectric ceramics, are uniformly illuminated, a high voltage, considerably exceeding the band gap energy, is generated. Along with this photovoltage, mechanical strain is also induced due to the converse piezoelectric effect. Photostrictive materials offer the potential for actuators with many advantages over traditional transducing electromechanical actuators made of shape memory alloys and electroceramics (piezoelectric and electrostrictive). Drawback of traditional actuators is that they require hard-wired connections to transmit the control signals which introduce electrical noise into the control signals; on the other hand PLZT actuators offer non-contact actuation, remote control, and immune from electric/magnetic disturbances. Some experimental research has been conducted on the use of PLZT materials, such as optical motor as an electromechanical device suitable for miniaturization, micro-waking machine, photo driven relay device using PLZT bimorphs and high speed (less than 10 ns), low-voltage, low power consumption optical switch. Authors have developed a computational method and implemented in an in-house finite element code which will be useful for designing systems incorporating thin film photostrictive actuators. The purpose of this current research work is to design and develop an experimental test set-up for photostriction effect measurement of PLZT thin film of different thickness, size and location on silicon wafer as smart beams, which may be useful for various MEMS device as optical actuator. The experimental results will be verified by comparing with the FEA modeling results.

scholarly journals Modeling and observation of mid-infrared nonlocality in effective epsilon-near-zero ultranarrow coaxial apertures

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Daehan Yoo ◽  
Ferran Vidal-Codina ◽  
Cristian Ciracì ◽  
Ngoc-Cuong Nguyen ◽  
David R. Smith ◽  
...  
Keyword(s):  
Field Enhancement ◽  
Atomic Layer ◽  
Atomic Scale ◽  
Large Area ◽  
Infrared Sensors ◽  
Mid Infrared ◽  
Critical Gap ◽  
Nanophotonic Devices ◽  
Extreme Scale ◽  
Epsilon Near Zero

Abstract With advances in nanofabrication techniques, extreme-scale nanophotonic devices with critical gap dimensions of just 1–2 nm have been realized. Plasmons in such ultranarrow gaps can exhibit nonlocal response, which was previously shown to limit the field enhancement and cause optical properties to deviate from the local description. Using atomic layer lithography, we create mid-infrared-resonant coaxial apertures with gap sizes as small as 1 nm and observe strong evidence of nonlocality, including spectral shifts and boosted transmittance of the cutoff epsilon-near-zero mode. Experiments are supported by full-wave 3-D nonlocal simulations performed with the hybridizable discontinuous Galerkin method. This numerical method captures atomic-scale variations of the electromagnetic fields while efficiently handling extreme-scale size mismatch. Combining atomic-layer-based fabrication techniques with fast and accurate numerical simulations provides practical routes to design and fabricate highly-efficient large-area mid-infrared sensors, antennas, and metasurfaces.

Preparation of Strongly Hydrophobic Film with Large Area and Flexibility Based on Micro Fabrication

2015 ◽  
Vol 645-646 ◽  
pp. 195-200
Author(s):  
Yi Bo Zeng ◽  
Ting Ting Wang ◽  
Jian Yan Wang ◽  
Hang Guo
Keyword(s):  
Silicon Wafer ◽  
Polyvinylidene Fluoride ◽  
Large Scale ◽  
Composite Layer ◽  
Scale Production ◽  
Micro Channel ◽  
Large Area ◽  
Micro Fabrication ◽  
Chemical Grafting ◽  
Micro Molding

In order to gain strongly hydrophobic film with large area and flexibility conveniently and effectively, how to prepare film with combination of technologies including micro fabrication, chemical grafting and micro molding is discussed. Firstly, micro channel arrays that the width is 5μm on the silicon wafer are prepared by micro fabrication. Then after spraying PVDF (Polyvinylidene Fluoride) lotion and pouring PDMS (Polydimethylsiloxane) glue solution onto the silicon wafer as the mould successively, the mixture need to be precured, which constructs rough structures in micro and nanoscale on the low surface energy film. Finally chemical grafting for film is carried out under the condition of O2 and 130°C so that the modification layer easy to adhesive on the boundary between PVDF and PDMS can be formed. Through the above technical routes, the strongly hydrophobic film that the general contact angle exceeds above 145o, the area is 180mm×64mm, the thickness is 0.9mm and the composite layer is firmly combined is gained. Compared to other hydrophobic materials the film is available in large area and has an advantage of flexibility. Meanwhile, the way that the film prepared by micro molding and in virtue of the silicon wafer with micro channel arrays as the mould contributes to large scale production.

scholarly journals An Indoor Positioning Approach Based on Fusion of Cameras and Infrared Sensors

Sensors ◽  
2019 ◽  
Vol 19 (11) ◽  
pp. 2519 ◽  
Author(s):  
Ernesto Martín-Gorostiza ◽  
Miguel A. García-Garrido ◽  
Daniel Pizarro ◽  
David Salido-Monzú ◽  
Patricia Torres
Keyword(s):  
Infrared Detectors ◽  
Low Cost ◽  
Indoor Positioning ◽  
Single Camera ◽  
Estimation Model ◽  
Infrared Sensors ◽  
Likelihood Estimator ◽  
Cost System ◽  
Independent Observations ◽  
The Difference

A method for infrared and cameras sensor fusion, applied to indoor positioning in intelligent spaces, is proposed in this work. The fused position is obtained with a maximum likelihood estimator from infrared and camera independent observations. Specific models are proposed for variance propagation from infrared and camera observations (phase shifts and image respectively) to their respective position estimates and to the final fused estimation. Model simulations are compared with real measurements in a setup designed to validate the system. The difference between theoretical prediction and real measurements is between 0.4 cm (fusion) and 2.5 cm (camera), within a 95% confidence margin. The positioning precision is in the cm level (sub-cm level can be achieved at most tested positions) in a 4 × 3 m locating cell with 5 infrared detectors on the ceiling and one single camera, at distances from target up to 5 m and 7 m respectively. Due to the low cost system design and the results observed, the system is expected to be feasible and scalable to large real spaces.

Energy Scavenging Combining Piezoelectric and Pyroelectric Effects

2010 ◽  
Author(s):  
Ugur Erturun ◽  
Rachel Waxman ◽  
Christopher Green ◽  
Matthew Lee Richeson ◽  
Karla Mossi
Keyword(s):  
Significant Interaction ◽  
Piezoelectric Effect ◽  
Electrical Power ◽  
Vibration Energy ◽  
Energy Scavenging ◽  
Vibration Energy Harvesting ◽  
Temperature Changes ◽  
Pyroelectric Effect ◽  
Cyclic Temperature ◽  
Sample Case

The piezoelectric effect is well known and used for vibration energy harvesting applications. The pyroelectric effect is also used to generate electrical power if there is an environment that has cyclic temperature changes. In this study, increasing generated electrical power by use of a combination of piezoelectric and pyroelectric effects is investigated. As a sample case it is aimed to utilize this piezoelectric and pyroelectric effect for a new sensor application. The results of the tests indicate that energy from vibrations and heat can have a significant interaction depending on the frequencies at which each effect occurs. In some cases, energy from vibrations and energy from heat can be detrimental when combined. Therefore both parameters have to be tuned properly to optimize scavenging energy. It was determined that at the best tested parameters the rate of charge increases by approximately 12%.

Piezoelectric effect in polyvinylidene fluoride at high frequencies

1973 ◽  
Vol 45 (6) ◽  
pp. 475-476 ◽  
Author(s):  
H. Sussner ◽  
D. Michas ◽  
A. Assfalg ◽  
S. Hunklinger ◽  
K. Dransfeld
Keyword(s):  
Polyvinylidene Fluoride ◽  
Piezoelectric Effect ◽  
High Frequencies
Sign in / Sign up

Export Citation Format

Share Document