Physicist demonstrates invisibility technology in Shanghai

In the future, everybody will have a Harry Potter invisibility cloak in the closet, said Chu junhao, an academician of the Chinese Academy of Sciences in Shanghai on Saturday.

At the Super Science Night held by Bilibili, China's major video-sharing platform, Chu showed how invisibility can be achieved with special technologies and materials.

He asked workers to hold a panel in front of him. Initially, the lower part of his body was visible through the panel. After rotating the panel 90 degrees, his lower half disappeared, but the stage behind him could still be clearly seen.

The magic was realized by a lenticular grating composed of rows of tiny cylindrical convex lenses, and each vertical cylindrical convex lens can shrink and thin objects parallel to it, so that light can be refracted, according to Chu.

When a row of cylindrical convex lenses forms a grating, several images that are too small to be noticed by the eyes are produced, achieving an invisibility effect.

He then showed several other ways to be invisible, such as using two substances with similar refractive indices and a plane mirror to create reflection imaging.

"Invisibility in science fiction will become reality as invisibility technology and material develop," he said. "More invisibility equipment will change our life, such as invisible rooms that can provide better privacy and invisible hearing-aids."

A netizen commented online that, "Technology is constantly advancing, and in the future, we might actually be able to wear invisibility clothing." Another one wrote that it is "a must-have for people with social anxiety when going out". But there are also netizens who are worried, "I don't need this item in my wardrobe, but I'm afraid that criminals would have it in theirs."

Chu, 78, is an infrared physicist, semiconductor physicist and device expert. He is president of the College of Science of Donghua University in Shanghai.