Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

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

15.03.2006


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:
http://www.utoronto.ca

More articles from Materials Sciences:

nachricht Graphene origami as a mechanically tunable plasmonic structure for infrared detection
25.04.2018 | University of Illinois College of Engineering

nachricht Scientists create innovative new 'green' concrete using graphene
24.04.2018 | University of Exeter

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Why we need erasable MRI scans

New technology could allow an MRI contrast agent to 'blink off,' helping doctors diagnose disease

Magnetic resonance imaging, or MRI, is a widely used medical tool for taking pictures of the insides of our body. One way to make MRI scans easier to read is...

Im Focus: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

World's smallest optical implantable biodevice

26.04.2018 | Power and Electrical Engineering

Molecular evolution: How the building blocks of life may form in space

26.04.2018 | Life Sciences

First Li-Fi-product with technology from Fraunhofer HHI launched in Japan

26.04.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>