Japanese scientist invents 'invisibility coat'

The coat makes the wearer appear see-through

A scientist at Tokyo University has developed a coat which makes those who wear it appear invisible.

Professor Susumu Tachi told the BBC's East Asia Today that the coat was made with a special type of "retro-reflective" material, which acts as a photographic screen.

If we paint a wall, then we can see behind it. Even if there is no window in the room, we can see the scenery outside

Professor Susumu Tachi

"We have a camera behind the person wearing the coat," Mr Tachi told the BBC.

The image from the camera is then projected onto the coat, so that the wearer appears virtually transparent when seen through a viewfinder.

Beforehand "it looks like a grey coat," Mr Tachi said. "But when we project the image onto it we can see a very clear picture of what is projected."

Medical application

The real purpose of the new technology is not to make a person appear see-through, however, but to augment reality, Mr Tachi said.

"Usually, virtual reality makes a computer-generated world with no direct relation to the real environment," he said. "What we would like to do is put virtual things in the real environment."

A prime example of this is in the medical field.

When surgeons are operating, they are unable to see any parts of their patient obscured by their own hands and equipment - a problem Mr Tachi hopes will be overcome by his invention.

"The surgeon sees the patient as if they are transparent, and can see the whole body structure," Mr Tachi said.

Another application is in housing. Retro-reflective technology can be applied to paint as well as clothing.

"If we paint a wall, then we can see behind it," Mr Tachi said. "Even if there is no window in the room, we can see the scenery outside."

The technology may also be useful for pilots, to make the floors of their cockpits appear transparent for landing.

While the invention is still in its experimental stages, Mr Tachi and his team hope to develop a commercially viable system within a few years.