Imagine whispering at one end of the Echo Wall in the Temple of Heaven in Beijing. Suddenly, you find that people a far will hear from 65 meters away. Such phenomena is known as the ‘whispering-gallery effect’.
As a result, scientists have now used the concepts of the whispering-gallery effect to stop counterfeiters in their tracks and create high-security identification. Despite the current high secure methods, identity theives can learn how to duplicate high complex patterns. To prevent this from happening, a pattern must be created that is impossible to duplicate.
"Instead of using sound waves, we used light waves to follow the concave surface of micrometer-size dye particles," explains Professor Yohei Yamamoto, senior author of the study. "This creates a complex color pattern that cannot be counterfeited."
Findings were published in Materials Horizons and describes a new, impenetrable anti-counterfeiting system.
"We attained a pixel density of several million per square centimeter on our optimized microchips," says Professor Yamamoto. "We have developed a high-security, two-step optical authentication system: the micropattern itself, and the underlying pixel-by-pixel fluorescence fingerprint of the microchip."
Source: Science Daily