Scientists are developing two types of invisibility cloaks. The first uses augmented reality and retro-reflective material to make a person appear invisible from a certain angle. The second uses metamaterials created by nanotechnology to reflect light and make objects hidden.
There are two versions of an invisibility cloak that scientists are working to perfect. The first uses augmented reality, which is a combination of computers, cameras and reflective surfaces to make a person appear invisible. The second invisibility cloak is made of metamaterials using nanotechnology.
The first invisibility cloak is sometimes called optical camouflage. A person wears a cloak made of a special reflective material. When viewed by an observer from a particular angle, that cloaked person disappears from view.
This invisibility cloak uses parts of a scientific branch called augmented reality technology. This technology provides useful information to complement the real world. An example of this is a handheld Global Positioning System (GPS) that provides useful information about a particular location, or a pair of glasses that overlay computer-generated information onto the real-world image seen by the wearer. Using some ideas behind this technology, scientists were able to make someone appear in the background.
The invisibility cloak itself is made of retro-reflective material. This special material has a raised surface as opposed to the standard flat surface of most reflective materials. Most reflective surfaces bounce light at a different angle than it entered, or scatter it into many smaller beams. The beads on the cape allow it to reflect light directly in the same direction in a single beam of light.
In effect, the coat transforms into a wearable movie screen. The wearer has a movie camera pointed behind him. The camera provides a real-time video feed to a remote computer. This computer processes the image and sends it to a projector the size of a pinhole. The projector filters the image through an iris diaphragm, which controls the passage of light and brightens the image. The image is eventually projected onto the cloak, making the person an exact reflection of what is happening behind them.
Another version of the invisibility cloak is in the works at Duke University. This alternate cloak uses metamaterials or materials with strange properties. In this case, reflective metamaterials created by nanotechnology work to create an object with a negative refractive index, making the objects unaffected by light waves. Materials must have a shorter wavelength than light for this to be effective, which is why nanotechnology is an essential part of science. If completed as intended, the fabric would reflect light directly onto the image and the object would essentially be hidden.
Protect your devices with Threat Protection by NordVPN
