3D CLOAKING DEVICE
The device makes objects seem see-through, while the image behind the object remains in focus. Two scientists used four standard, off-the-shelf lenses in a particular arrangement to keep an object hidden and the background undisturbed, as the viewer moves up to several degrees away from the optimal viewing angle.
It can be scaled up or down (on the condition that the lenses are available in the size and curvature). Some uses could include cloaking a trailer on the back of a semi-truck so the driver can see directly behind him. It can also be used in surgery so a surgeon can see through his hands to see what he is operating on, military, etc.