The scientists used the Pancharatnama-Berry Optical Element (PBOE), which is
The development was based on technologyartisans from China and Japan who lived thousands of years ago. They made mirrors of bronze, which were no different from ordinary ones when a person looked at his own reflection, but in direct sunlight they formed a different image.
The principle of operation of ancient devices, scientists have understoodonly at the beginning of the 20th century. The resulting effect is that the image cast on the back of the mirror creates slight variations that form the images. And the mathematical basis for this phenomenon was derived in 2005 by Michael Berry.
And only now engineers have been able to apply the same principle to liquid crystals, creating from them both a mirror and a window.
After making the "magic" mirror and window, the scientists used a camera to measure the saturation of the light they created.The laser beam created a visible image that remained constant even when the distance between the camera and the designed objects changed.The researchers also showed that the devices create images when illuminated by an LED light source.
Liquid crystals are materials that canflow like a normal liquid, but have molecules that can be oriented, as in solid crystals. In the new work, the researchers used a modified version of a well-known manufacturing process that creates a specific pattern of liquid crystal capable of producing the desired image when illuminated.
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