A research team from China and Singapore has used the refractive properties of glass to create a device that can cause objects to become invisible to observers, according to China’s official Xinhua News Agency.
A cat and a goldfish were successfully cloaked with invisibility by a device made of thin panels of glass that had been developed jointly by professor Chen Hongsheng of the Electromagnetics Academy of Zhejiang University and a research team from Singapore’s Nanyang Technological University.
The device works by causing light to bend around the cloaked objects. It can cloak the objects while moving along with them as well, said Chen.
The researchers capitalized on their finding that the human eye is not sensitive to light phases and incremental delays. They decided to use glass to manipulate light because it is transparent, has a smooth surface and is far less costly than refractive materials that rely on nanotechnology.
The invisibility cloak — which Chen says is still in a rudimentary state — is hexagonal in shape because it is most effective when light is shone directly at six angles. A polygonal device can only make objects invisible at two angles. The device works best when light is coming from a single source. Its effectiveness is also limited to a narrow spectrum of visible light.
Chen’s team expects to continue working to enhance the device for better invisibility and portability so it can become useful in the fields of security, entertainment and surveillance. The team’s work will be detailed in an article in last month’s edition of the online multidisciplinary journal Nature Communication.
