Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Pressable photonic crystals produce full-colour fingerprints and promise enhanced security


Experiment reveals layers of data missed by traditional ink fingerprints

In the future, law enforcement officials may take full-colour fingerprints using new technology developed by a University of Toronto-led team of international researchers.

Far from the basic black-and-white fingerprints collected today, the new technology would use elastic photonic crystals to capture data-rich fingerprints in multiple colours, but the fingerprinting technique is just one potential application for the new technology. A paper on the new research is featured on the cover of the current issue of the journal Nature Materials.

"You can elastically deform these crystals and produce different colours," says lead author André Arsenault, a PhD candidate in the laboratory of Geoffrey Ozin, a University Professor in the Department of Chemistry and a Canada Research Chair in materials chemistry.

Photonic crystals are a relatively new development in the scientific quest to control light. Ozin’s lab first created photonic crystals in 2002, using spherical particles of silica mere micrometres in diameter that self-assemble into neat layers, creating what’s known as an opal. After filling the space between the spheres with silicon, they used acid etching to remove the silica balls. This left an ordered sponge of air bubbles in silicon known as an inverse opal. This photonic crystal material, the first of its kind, did indeed trap light. These photonic crystals can produce colour based on how an electromagnetic wave interacts with the structure -- meaning that it could be tuned to produce any colour.

In the new study, the team injected an elastic compound between the spheres, which were then etched away, leaving an orderly and compressible elastic foam that can be transferred onto virtually any surface, such as glass, metal or plastic. The material changes colour based on how far the spheres are separated.

"The material we have is very, very thin," Arsenault says. "We can coat it onto any surface we want." If the foam is compressed, it alters the lattice dimensions, changing the wavelength of light that it produces. The team demonstrated the fingerprint application, using Arsenault’s finger, and produced both still images and a video of the process, which captures detailed information about pressure patterns and surface ridges that may not be visible to the naked eye.

Taking it one step further, Arsenault made a rubber replica of his fingertip, which might fool a traditional fingerprint scan. "If you press the rubber replica into the material, the pressure impressions that you get are very different," he says. "The lines are much sharper, because the material is less soft. From the standpoint of biometrics, this could provide better security."

Arsenault says the technology could be used not only for colour fingerprints, but in sensors for air-bag release mechanisms in cars, strain and torque sensors on support beams of high-rise buildings and in laser sources. The study was funded by the Natural Sciences and Engineering Research Council of Canada, the University of Toronto, EC NoE Phoremost and Deutsche Forschungsgemeinschaft.

Nicolle Wahl | EurekAlert!
Further information:

More articles from Materials Sciences:

nachricht From ancient fossils to future cars
21.10.2016 | University of California - Riverside

nachricht Study explains strength gap between graphene, carbon fiber
20.10.2016 | Rice University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>