Scientists at the University of St Andrews in Scotland have created an ultra-thin flexible film capable of emitting laser light. Researchers have successfully tested it on contact lenses, demonstrating the real ability to release laser beams from the eyes. Scientists reported on the work done in the journal Nature Communications.
Don't rush to run and buy the Cyclops visor. The laser beam produced by this film is very weak and will not cause any damage. And the technology itself, scientists say, rather has the potential to be used in the creation of wearable security tags or, perhaps, even as a kind of wearable barcode.
“We have demonstrated the manufacturing process and operation of a low-power laser film that is safe for organic applications, is very flexible and very lightweight. Its physical properties, combined with the ability to generate a low-power laser beam with various output spectrum parameters, allow it to be used for the production of security labels and applied on a wide variety of surfaces, including banknotes, contact lenses and nails,”the scientists report in the published article.
The film thickness is less than one thousandth of a millimeter. In addition, it is flexible, so it can be easily adapted for use, for example, in polymer banknotes or in soft plastic products, for example, in the same flexible contact lenses.
According to the IEEE Spectrum portal, the film creates a laser beam using nanoscale lattices imprinted on its thin polymer membranes. The resulting membranes can then be integrated into other surfaces, scientists say.
When illuminated with another laser, the film begins to emit its own laser beam with a wavelength of 420-700 nanometers, which is determined by the structure and material of the grating. However, the researchers note that if desired, the parameters can be adjusted to suit your needs, and then the film will emit its wavelength and even emit the laser as a coded signal in the form of zeros and ones, as in a barcode.
The diagram shows how a laser membrane can be used as counterfeit protection in polymer banknotes.
The laser produced by the film is very low-power - about one nanowatt. This is one billionth of a watt, which is extremely small even to create barely visible light. But this power is enough for the laser beam to be recognized by the scanner, which opens the prospect for the film to be used as the basis for safety tags, scientists say.
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“In this case, it will be very difficult to fake a laser beam with the correct wavelength,” comments senior researcher, physicist Malte Gater of the University of St Andrews.
To test the film's functionality, the team integrated the membrane into contact lenses and then used it on an existing removed cow's eye (image above). They are often used in such tests because they have similar structural features to the human eye. In addition, there is usually no shortage of test material in this case.
The film was also tested by placing it on the nail of one of the researchers. In both cases, the membrane produced a laser beam, and, more importantly, its power was constantly in the safe zone, which indicates the possibility of its repeated safe use in the same contact lenses.
According to the developers, the transition from prototype to mass production of such a film can be established without problems.
“Using the newly developed roll-to-roll nano-printing technology and organic ink technology, it is possible to mass-produce laser films at a low cost of the final product,” the scientists noted.
Nikolay Khizhnyak
