Materiale si echipamente cu proprietati in mascarea in domeniul vizibil ,IR , al undelor radar sau care pot avea proprietati in mimetism – Pagina 4

Tricou de flanel tactic Tricou de lucru cu maneci lungi pentru cămașă de mânecă lungă pentru Lo-Pro / Lo-Vis (cu profil redus / vizibilitate redusă) și cămașa ascunsă (CCW): cămașă funcțională și funcțională pentru a rămâne sub radar în timpul misiunilor și Voiaj!(Tactical Flannel Shirt Valiant Blue Plaid Long-Sleeve Work Shirt for Lo-Pro/Lo-Vis(low-Profile/Low-Visibility) Ops and Concealed Carry(CCW):Great-Looking and Functional Shirt for Staying Under the radar During Missions and Travel!)

cu profil redus / vizibilitate redusă) și cămașa ascunsă (CCW): cămașă funcțională și funcțională pentru a rămâne sub radar în timpul misiunilor

8 sept

Sculele de sticla folosesc lumina scurgeri pentru camuflaj eficient(Squids use leaking light for effective camouflage)

Oamenii de stiinta au descoperit ca celulele bioluminiscente gasite in unele calmaruri de sticla sunt din punct de vedere biologic ineficiente.Sculele de sticlă au proprietăți remarcabile pentru evitarea detectării

Stimpex 7

Tuningul prin ionizare ajută oamenii de știință să urmărească modificările ultra-rapide ale moleculelor ( Tunneling ionization helps scientists to track ultrafast changes in molecules )

ambele întrebări.
Holografia holografică vă permite să reconstruiți imaginile tridimensionale ale obiectelor. Baza fizică a metodei este de a înregistra un model de interferență a undelor provenite de la o sursă (unde de referință) și a reflectat un obiect (val de obiect). Caracteristicile structurale ale obiectului modifică faza undei obiectului, iar modelul de interferență stochează această informație – volumul și „structura” obiectului înregistrat pe hologramă.
În holografia fotoelectronică, în locul unui val de referință, există electroni care zboară direct spre un detector după procesul de ionizare a tunelului. Valul obiectului corespunde cu electronii care, pe drum spre detector, sunt mai întâi împrăștiați pe ionul părinte. Sa constatat că holograma codifică informații despre faza amplitudinii împrăștierii elastice a electronului pe ion. Această fază poate fi utilizată pentru a restabili structura ionului.

Posted: Jun 09, 2016
Tunneling ionization helps scientists to track ultrafast changes in molecules (Nanowerk News) Using tunneling ionization and ultrashort laser pulses, scientists have been able to observe the structure of a molecule and the changes that take place within billionths of a billionth of a second when it is excited by an electron impact.
Oleg Tolstikhin, a Russian physicist from MIPT, and his colleagues from Japan and China have discovered a method of “looking” into molecules and obtaining information about their structure using electron interference patterns. They also conducted an experiment demonstrating the ability to track changes in a molecule during the transition of an electron to an excited state. The findings were presented in two papers published in Physical Review Letters („Imaging Electronic Excitation of NO by Ultrafast Laser Tunneling Ionization” and „Near-Forward Rescattering Photoelectron Holography in Strong-Field Ionization: Extraction of the Phase of the Scattering Amplitude”).
Tolstikhin and his colleagues are working in the field of attophysics – a science which looks at very fast processes (1 attosecond, as = 10-18s) such as the restructuring of electron shells or the displacement of atomic nuclei in molecules during chemical reactions. Their main objective is to learn to recognise how the structure of molecules changes with attosecond time resolution. i.e. billionths of a billionth of a second.
One method is to use tunneling ionization. A strong laser pulse is directed at a molecule, which causes electrons to break away due to the quantum tunneling effect. As we can say with certainty that ionization took place within a small fraction of a laser cycle (the duration of one complete oscillation of the electromagnetic field in the laser irradiation used at a wavelength of 800 nm is approximately 2.5 femtoseconds), the proposed method allows scientists to observe rapidly occurring processes within the molecule.
“Attophysics is currently a “fundamental science”, but we are still able to suggest a range of applications: by knowing the way in which a shell configuration changes, or the way nuclei move during a chemical reaction, we can “shoot” a laser in the right place at the right time to produce a controlled outcome in a chemical reaction,” says Oleg Tolstikhin, Chief Researcher and Associate Professor of MIPT’s Theoretical Physics Devision and Head of the Attosecond Physics Group.
Tunneling ionization from the excited state of a molecule
The first paper describes an experiment in which and his colleagues from Nagoya University and The University of Electro-Communications in Tokyo used few-cycle laser pulses of different wavelengths to irradiate molecules of nitric oxide (NO). A weak UV pulse excited an outer electron to a higher state, followed by a strong infrared pulse creating a field in which the electron escaped from the molecule due to the tunneling effect. After breaking away from the molecule in the strong laser field, the electron returned and was scattered on a molecular ion, which resulted in the molecule dissociation into a positive nitrogen ion and an oxygen atom. The scientists then measured the momentum distribution of nitrogen ions for the ground and excited initial initial states.

Fig.1. Momentum distribution of N+ ions for an initial NO molecule in the ground (a and c) and excited (b and d) electronic states. The points denote the experimental results. The solid lines are the results of theoretical calculations. (Image courtesy of the author of the paper)
From this image, the scientists were able to track the dependence of the rate of tunneling ionization on the orientation of the molecule with respect to the laser polarization direction. It was found that in the ground state of the molecule, tunneling ionization is most likely to occur when the axis of the molecule is at an angle of 45° to the direction of the oscillation of the electric field, and in the excited state the distribution is almost isotropic, i.e. the same in all directions (Fig.1). The results of the experiment are consistent with the predictions of the weak-field asymptotic theory of tunneling ionization.
The good agreement between the experimental results and the theoretical calculations, and the high time resolution suggest that the method could potentially be used to visualize molecular configurations in real time, which means they could be observed dynamically and controlled effectively.
Photoelectron holography
The second paper is purely theoretical. It examines the development of a new method that enables scientists to “extract” structural information from spectra of photoelectron scattering in tunneling ionization of an atom or molecule. The numerical experiment is similar to the real experiment conducted with nitric oxide: the atom is irradiated with a strong femtosecond laser pulse. But instead of a momentum distribution of N+ ions, the scientists studied an interference pattern of photoelectrons that had tunneled from the outer shell of the atom.
Certain ionized electrons ultimately have the same momentum and this means that they are able to interfere. The time in which the photoelectrons are able to fly “back and forth” in a laser field and return for rescattering on the parent ion is comparable with the length of the optical cycle of the laser (a few femtoseconds). However, the observed interference pattern has a much narrower “time” structure – it encodes processes that last for attoseconds. This means that it is possible to observe what happened with an atom or a molecule in the time between the tunneling of an electron and its return to the ion with attosecond resolution.
Previously, scientists demonstrated that the momentum distribution in an experiment with tunneling ionization contains a stable interference structure that must store information about the composition of the parent ion (Science, „Time-Resolved Holography with Photoelectrons”). This structure was called a photoelectron hologram, similar to an optical hologram. However, precisely what structural information is encoded in the hologram and how to decode it from there was still a puzzle. Oleg Tolstikhin and his colleagues from China and Japan provided an answer to both of these questions.
Optical holography allows you to reconstruct three-dimensional images of objects. The physical basis of the method is to record an interference pattern of waves coming from a source (reference wave) and reflected off an object (object wave). The structural features of the object alter the phase of the object wave, and the interference pattern stores this information – the volume and “structure” of the object recorded on the hologram.
In photoelectron holography, instead of a reference wave there are electrons that fly directly to a detector after the process of tunneling ionization. And the object wave corresponds to electrons that, on their way to the detector, are first scattered on the parent ion. It was found that the hologram encodes information on the phase of the elastic scattering amplitude of the electron on the ion. This phase can be used to restore the structure of the ion. The results of the numerical calculations very well agree with the predictions of the adiabatic theory, which confirms the validity of the theoretical conclusions made.
“In our study, we consider a model atom with one electron – but this is only to simplify the calculations. We demonstrate the principle of extracting the phase of the complex scattering amplitude from the photoelectron momentum distributions and this procedure should apply to all atoms and molecules,” says Oleg Tolstikhin commenting on the study.

Source: Moscow Institute of Physics and Technology

Subscribe to a free copy of one of our daily Nanowerk Newsletter Email Digests with a compilation of all of the day’s news.

Cercetătorii determină limitele fundamentale ale mantalelor de invizibilitate ( Researchers determine fundamental limits of invisibility cloaks)

o tehnologie care permite obiectelor să devină invizibile sau nedetectabile undelor electromagnetice, inclusiv undele radio, Microunde, infraroșu și lumină vizibilă.Mantalele sunt fabricate din materiale artificiale, numite metamateriale, care au proprietăți speciale care permit un control mai bun al undelor de intrare și pot face un obiect invizibil sau transparent. Limitele nou stabilite se aplică pe mantalele fabricate din metamateriale pasive – cele care nu atrag energia de la o sursă de energie externă.

Posted: Jul 06, 2016
Researchers determine fundamental limits of invisibility cloaks (Nanowerk News) Researchers in the Cockrell School of Engineering at The University of Texas at Austin have been able to quantify fundamental physical limitations on the performance of cloaking devices, a technology that allows objects to become invisible or undetectable to electromagnetic waves including radio waves, microwaves, infrared and visible light.
The researchers’ theory confirms that it is possible to use cloaks to perfectly hide an object for a specific wavelength, but hiding an object from an illumination containing different wavelengths becomes more challenging as the size of the object increases.
Andrea Alù, an electrical and computer engineering professor and a leading researcher in the area of cloaking technology, along with graduate student Francesco Monticone, created a quantitative framework that now establishes boundaries on the bandwidth capabilities of electromagnetic cloaks for objects of different sizes and composition. As a result, researchers can calculate the expected optimal performance of invisibility devices before designing and developing a specific cloak for an object of interest. Alù and Monticone describe their work in the journal Optica („Invisibility exposed: physical bounds on passive cloaking”).

The graph shows the trade-off between how much an object can be made transparent (scattering reduction; vertical axis) and the color span (bandwidth; horizontal axis) over which this phenomenon can be achieved. The red line represents the optimal performance achievable by a passive cloak, dividing the graph in realizable and forbidden regions. No passive invisibility device can attain performance values belonging to the forbidden region. Achieving invisibility becomes more and more challenging for bigger objects (the red line representing the bound moves upward and to the left, as indicated by the arrow). (Image: Cockrell School of Engineering)
Cloaks are made from artificial materials, called metamaterials, that have special properties enabling a better control of the incoming wave, and can make an object invisible or transparent. The newly established boundaries apply to cloaks made of passive metamaterials – those that do not draw energy from an external power source.
Understanding the bandwidth and size limitations of cloaking is important to assess the potential of cloaking devices for real-world applications such as communication antennas, biomedical devices and military radars, Alù said. The researchers’ framework shows that the performance of a passive cloak is largely determined by the size of the object to be hidden compared with the wavelength of the incoming wave, and it quantifies how, for shorter wavelengths, cloaking gets drastically more difficult.
For example, it is possible to cloak a medium-size antenna from radio waves over relatively broad bandwidths for clearer communications, but it is essentially impossible to cloak large objects, such as a human body or a military tank, from visible light waves, which are much shorter than radio waves.
„We have shown that it will not be possible to drastically suppress the light scattering of a tank or an airplane for visible frequencies with currently available techniques based on passive materials,” Monticone said. „But for objects comparable in size to the wavelength that excites them (a typical radio-wave antenna, for example, or the tip of some optical microscopy tools), the derived bounds show that you can do something useful, the restrictions become looser, and we can quantify them.”
In addition to providing a practical guide for research on cloaking devices, the researchers believe that the proposed framework can help dispel some of the myths that have been developed around cloaking and its potential to make large objects invisible.
„The question is, ‘Can we make a passive cloak that makes human-scale objects invisible?’ ” Alù said. „It turns out that there are stringent constraints in coating an object with a passive material and making it look as if the object were not there, for an arbitrary incoming wave and observation point.”
Now that bandwidth limits on cloaking are available, researchers can focus on developing practical applications with this technology that get close to these limits.
„If we want to go beyond the performance of passive cloaks, there are other options,” Monticone said. „Our group and others have been exploring active and nonlinear cloaking techniques, for which these limits do not apply. Alternatively, we can aim for looser forms of invisibility, as in cloaking devices that introduce phase delays as light is transmitted through, camouflaging techniques, or other optical tricks that give the impression of transparency, without actually reducing the overall scattering of light.”
Alù’s lab is working on the design of active cloaks that use metamaterials plugged to an external energy source to achieve broader transparency bandwidths.
„Even with active cloaks, Einstein’s theory of relativity fundamentally limits the ultimate performance for invisibility,” Alù said. „Yet, with new concepts and designs, such as active and nonlinear metamaterials, it is possible to move forward in the quest for transparency and invisibility.”

Source: University of Texas at Austin

Cercetătorii mimează nanostructurile fluturelor pentru tehnologii compacte noi(Researchers mimic butterfly wing nanostructures for compa)ct new technology

au dezvoltat o tehnică care ar putea fi folosită pentru a face ecrane mai strălucitoare pe computer;spune că materialele realizate din aceste giroscoape artificiale trebuie să răspundă la lumină la viteze altrafast, făcându-le ideale pentru comutatoarele de mare viteză

Researchers

Revizie SnowHawk Sistemul de protecție împotriva vremii la rece / Balaclava în Hyde Definiție PenCott-Snowdrift Arctic Combat Camo (Camuflaj) Model pentru Arctic Warfare Ops(Revision SnowHawk Cold Weather Goggle System/Balaclava in Hyde Definition PenCott-Snowdrift Arctic Combat Camo (Camouflage) Pattern for Arctic Warfare Ops)

Sistemul de revizie SnowHawk Weather Goggle, conceput și dezvoltat special pentru operațiunile de război arctic, este, în esență, o balustradă foarte confortabilă care încorporează tehnologia Anon’s Integration Magnetic Facemask (MFI®) pentru a „integra perfect ochelarii și balaclava, asigurând stabilizarea și sigilarea pielea expusă „, realizând acoperirea totală a capului și a feței, ușurința în utilizare, îndepărtarea rapidă și confortul. Revizuirea aplică, de asemenea, stratul de acoperire Revoluția OcuMax Plus în interiorul obiectivului pentru ochelari de protecție pentru a preveni formarea de ceață și o acoperire cu strat dur pe partea exterioară a obiectivului pentru a preveni zgârierea.

Revision SnowHawk Cold Weather Goggle System/Balaclava in Hyde Definition PenCott-Snowdrift Arctic Combat Camo (Camouflage) Pattern for Arctic Warfare Ops! (Photos!)

Posted by: David Crane June 2, 2016

Speaking of combat/tactical gear and clothing in Hyde Definition PenCott combat camo (camouflage) patterns, DefenseReview (DR) also got a look at the Revision SnowHawk Cold Weather Goggle System/balaclava in Hyde Definition PenCott-Snowdrift arctic combat camo pattern at SOFIC 2016 (Special Operations Industry Conference 2016). The Revision SnowHawk Cold Weather Goggle System was developed with the assistance of Anon Optics (a Burton Snowboards brand), which supplied the goggle portion of the system.

The Revision SnowHawk Cold Weather Goggle System, designe and developed specifically for arctic warfare operations, is essentially a very comfortable balaclava that incorporates Anon’s Magnetic Facemask Integration (MFI®) technology to “seamlessly integrate the goggle and balaclava, ensuring stabilization and seal, with no skin exposed,” achieving total head and face coverage, ease of use, swift removal, and comfort. Revision also applies the Revision OcuMax Plus coating to the inside of the goggle lens to prevent fogging, and a hard-coat coating on the outside of the lens to prevent scratches.

It’s a nice looking system, particularly with the PenCott-Snowdrift arctic combat camo pattern applied, and will likely be greatly enjoyed by military Special Operations Forces (SOF) tasked with arctic warfare missions. On a side note, DefenseReview wouldn’t mind seeing balaclavas in Hyde Definitions’ other PenCott camo patterns, including Pencott-GreenZone and Pencott Badlands.

The following is Revision’s official press release on the SnowHawk Cold Weather Goggle System:

“Essex Junction, Vermont (May 23, 2016) – Revision Military, a world leader in protective eyewear solutions, introduces the SnowHawk™ Cold Weather Goggle System. Revision developed this goggle system in collaboration with Anon Optics, a leader in goggle design for snow sports and a brand owned by Burton Snowboards, the world’s leading snowboard company. The SnowHawk Cold Weather System is the first-ever fully integrated ballistic goggle and balaclava system offering complete face coverage, superior anti-fog performance, and ballistic protection.

Cold climate operations have become an essential tactical focus for militaries around the world, with many dedicating more resources and training to maneuvers in the Arctic and other cold weather regions. This shift has generated a growing demand for gear that can withstand harsh conditions and function in extreme environments. Extensive time, attention, and resources were dedicated to ensuring the breathability of this cold weather system: Mesh over the mouth and nose directs breath away from the goggle; the dual-pane thermal gasket lens creates an insulated barrier; built-in top and lateral forced-air vents provide constant airflow; and, Revision’s leading OcuMax© Plus coating is applied on the inside of the lens to prevent fogging, plus a hard-coat is on the outside of the lens to resist scratching. The SnowHawk system’s balaclava design utilizes Anon’s Magnetic Facemask Integration (MFI®) technology to seamlessly integrate the goggle and balaclava, ensuring stabilization and seal, with no skin exposed. The system achieves total face and head coverage, but is also intuitively designed for ease of use and swift removal when necessary. The SnowHawk Cold Weather System is available in black or winter white.

“As Revision has evolved, we have increasingly taken advantage of our cutting-edge facilities to tailor our protective equipment to the many environments forces around the world encounter,” said Jim Hester, Vice President, Optics, Revision Military. “We are excited to take this capability to greater extremes and challenge the limits of what our protective eyewear can do with the SnowHawk Cold Weather Goggle System. We are especially pleased to partner with a neighboring Vermont company on this venture. Burton is a likeminded and impressive company in an adjacent field, and it brings a wealth of experience and a fresh perspective to the table.” Hester continued, “As extreme cold weather operations are expanded, the SnowHawk goggle system, and the technology we have developed for this product, will be the standard for integrated head systems used by forces in extreme cold conditions.”SnowHawk_Headform_FloatingAbove: Revision’s SnowHawk Cold Weather Goggle is shown in Arctic white and Black configurations.

With improved comfort, functionality, and stability comes enhanced endurance and situational awareness; this is especially vital in the harshest and most unforgiving terrain on the planet. The SnowHawk Cold Weather System is low-profile and lightweight, with a sleek form-factor ideal for both tactical operations and extended-use missions. This efficient design ensures compatibility with helmets, binoculars, and night vision systems. The SnowHawk goggle lenses are interchangeable—with options for bright sunlight, overcast or low-light scenarios, and laser protection—and are made from optical grade polycarbonate to shield eyes from unexpected fragments, exceeding U.S. Military eyewear ballistic impact resistance requirements (MIL-PRF-32432).
SnowHawk goggles are compatible with Revision’s Rx Carrier for prescription lenses up to ±11D. Revision has tested the SnowHawk Cold Weather Goggle System in the company’s Research & Development laboratory, and the SnowHawk system has undergone rigorous review by multiple organizations in many diverse environments and conditions, including in Alaska, California, Norway, Canada, and atop Mount Washington, NH, a location known to be one of the coldest and harshest in the U.S. For additional information on this product and Revision’s capabilities, or for purchase inquires, contact [email protected].

ABOUT REVISION
Revision develops and delivers purpose-built protective soldier equipment for military use worldwide. The company, which began with eyewear, has expanded to face, head and torso protection as well as energy storage and power management products, continues to develop innovative capabilities for integrated, performance-enhancing soldier systems. To that end, Revision brings together the most advanced expertise, state-of-the-art facilities and finest technical minds. Privately owned and ISO 9001:2008 certified, Revision’s operational headquarters is located in Essex Junction, Vermont, USA, with additional offices in Montreal, Canada, The UK, and Luxembourg. For more information, visit www.revisionmilitary.com, write [email protected], or call +1 802-879-7002.”

Company Contact Info:

Revision
7 Corporate Drive
Essex Junction VT
05452 USA
Phone: 802.879.7002
Toll-Free: 800.383.6049
Fax: 802.879.7224
Email Contact Page: https://www.revisionmilitary.com/contact-us/
Website: https://www.revisionmilitary.com

Hyde Definition Ltd
Chapel View, Mill Road
Hempnall, Norfolk
NR15 2LP, UK
Phone: +44 (0)1508 499704
Email: [email protected]
Website: http://www.pencottcamo.com

Anon Optics
Email Contact Page: http://anonoptics.com/contact
Website: http://anonoptics.com

Optica de descoperire pentru a revigora viziunea de noapte(Optics breakthrough to revamp night vision)

Dispozitivele infraroșii sunt utilizate pentru o vizibilitate îmbunătățită prin ceață și pentru vizibilitate nocturnă și pentru observații care nu sunt posibile cu lumină vizibilă

Optics

Nanowire ferestre reglabile pentru intimitate, camuflaj(Tunable nanowire windows for privacy, camouflage)

au dezvoltat o tehnică care poate schimba rapid opacitatea unei ferestre, transformându-o în ceață, clară sau undeva între ele, cu mișcarea unui comutator.

Posted: Mar 14, 2016
Tunable nanowire windows for privacy, camouflage (Nanowerk News) Say goodbye to blinds.
Researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences have developed a technique that can quickly change the opacity of a window, turning it cloudy, clear or somewhere in between with the flick of a switch.
Tunable windows aren’t new but most previous technologies have relied on electrochemical reactions achieved through expensive manufacturing. This technology, developed by David Clarke, the Extended Tarr Family Professor of Materials, and postdoctoral fellow Samuel Shian, uses geometry adjust the transparency of a window.
The research is described in journal Optics Letters („Electrically tunable window device”).

The tunable window is comprised of a sheet of glass or plastic, sandwiched between transparent, soft elastomers sprayed with a coating of silver nanowires, too small to scatter light on their own.
But apply an electric voltage and things change quickly.
With an applied voltage, the nanowires on either side of the glass are energized to move toward each other, squeezing and deforming the soft elastomer. Because the nanowires are distributed unevenly across the surface, the elastomer deforms unevenly. The resulting roughness causes light to scatter, turning the glass opaque.
The change happens in less than a second.
It’s like a frozen pond, said Shian.
„If the frozen pond is smooth, you can see through the ice. But if the ice is heavily scratched, you can’t see through,” said Shian.
Clarke and Shian found that the roughness of the elastomer surface depended on the voltage, so if you wanted a window that is only lightly clouded, you would apply less voltage than if you wanted a totally opaque window.
„Because this is a physical phenomenon rather than based on a chemical reaction, it is a simpler and potentially cheaper way to achieve commercial tunable windows,” said Clarke.
Current chemical-based controllable windows use vacuum deposition to coat the glass, a process that deposits layers of a material molecule by molecule. It’s expensive and painstaking. In Clarke and Shian’s method, the nanowire layer can be sprayed or peeled onto the elastomer, making the technology scalable for larger architectural projects.
Next the team is working on incorporating thinner elastomers, which would require lower voltages, more suited for standard electrical supplies.
Harvard’s Office of Technology Development has filed a patent application on the technology and is engaging with potential licensees in the glass manufacturing industry.

Source: Harvard John A. Paulson School of Engineering and Applied Sciences

Echipa de cercetare realizează un fotodetector cu 3 culori(Research team realizes 3-color photodetector)

fotodetector cu infraroșu cu infraroșu cu infraroșu cu trei culori, cu undă scurtă. Cu noul design, dispozitivele pot detecta diferite benzi de frecvență în infraroșu prin simpla variație a tensiunii aplicate. Acest lucru ar putea deschide o gamă largă de aplicații potențiale, inclusiv televizoare color infraroșu și imagini în infraroșu cu trei culori.
„Un dispozitiv capabil să detecteze diferite valuri de infraroșu este foarte de dorit în sistemele de imagistică infraroșie de nouă generație

Posted: Apr 22, 2016
Research team realizes 3-color photodetector (Nanowerk News) While infrared waves are available in short, mid, and long lengths, most detection devices are unable to harness all three at the same time.
Now Northwestern University’s Manijeh Razeghi and her team have developed a new approach in device design to realize a three-color, shortwave-midwave-longwave infrared photodetector. With the new design, the devices can detect different infrared wavebands by simply varying the applied bias voltage. This could open up a range of potential applications, including infrared color televisions and three-color infrared imaging.
„A device capable of detecting different infrared wavebands is highly desirable in the next generation infrared imaging systems,” said Razeghi, Walter P. Murphy Professor of Electrical Engineering and Computer Science in Northwestern’s McCormick School of Engineering.
Supported by DARPA, the Army Research Laboratory, Air Force Research Laboratory, and NASA, the team’s finding were published on April 7 in Nature Scientific Reports („High performance bias-selectable three-color Short-wave/Mid-wave/Long-wave Infrared Photodetectors based on Type-II InAs/GaSb/AlSb superlattices”).
Led by Razeghi, the researchers invented and investigated the new design for three-color photodiodes without using additional terminal contacts. The resulting photodetector is based on indium-arsenide/gallium-antimonide/aluminum-antimonide type-II superlattices.
As the applied bias voltage varies, the photodetector sequentially exhibits the behavior of three different colors, corresponding to the bandgap of three absorbers, and achieves well-defined cut-off wavelengths and high-quantum efficiency in each channel.
This new research builds on the Razeghi group’s many years of work in Northwestern’s Center for Quantum Devices, including the development of the first single-color, short-wavelength infrared photodetector and two-color, shortwave-midwave infrared photodetector based on type-II superlattices.
„I am fascinated by these results,” Razeghi said. „The initial success in this demonstration will drive us to the new frontier of infrared detection and imaging technology.”

Source: Northwestern University

Tactical Night Vision Compania TNVC GoPro NVG (Night Vision Goggle) Adaptor pentru GoPro HERO Seria 4 și Seriile HERO Sisteme de cameră rezistent la apă(Tactical Night Vision Company TNVC GoPro NVG(Night Vision Goggle) Adapter for GoPro HERO 4 Series and HERO Session Waterproof Camera Systems)

Aprecierea Apărării a fost cu adevărat impresionată de cele două unități pe care le-am văzut la SHOT și ne-ar plăcea să obținem o unitate pentru următoarea dinamică CQB / CQC forțată-for-force (aproape Quarters Battle / Close Quarters Combat) curs de luptă ușoară

Tactical

Pachetul de siguranță Condor Elite Fail Safe-Pack / Lo-Pro / Covert Urban Assault Pack (Rucsac) cu capacitate de hidratare Combat / Tactil(Condor Elite Fail Safe Pack Lo-Pro/Lo-Vis Covert Urban Assault Pack(Backpack) with Combat /Tactil Hydration Capability)

a prezentat recent unul dintre cele mai tari cele care au aparut in cadrul show-ului SHOT Show 2016, ca parte a liniei de produse relativ noi Condor Elite
Primul lucru pe care Dunn i la explicat lui DR a fost motivul pentru care a fost dat pachetului Safe Fail Safe, datorită influenței moderne a designului pachetului de parașute,

Condor