04-06-2012, 01:47 PM
A retro-reflective material
is covered with thousands and thousands of small beads. When light strikes one of these beads, the light rays bounce back exactly in the same direction from which they cameTo understand why this is unique, look at how light reflects off of other types of surfaces. A rough surface creates a diffused reflection because the incident (incoming) light rays get scattered in many different directions. A perfectly smooth surface, like that of a mirror, creates what is known as a specular reflection -- a reflection in which incident light rays and reflected light rays form the exact same angle with the mirror surface. In retro-reflection, the glass beads act like prisms, bending the light rays by a process known as refraction. This causes the reflected light rays to travel back along the same path as the incident light rays. The result: An observer situated at the light source receives more of the reflected light and therefore sees a brighter reflection
ALTERED REALITY
Optical camouflage doesn't work by way of magic. It works by taking advantage of something called augmented-reality technology -- a type of technology that was first pioneered in the 1960s by Ivan Sutherland and his students at Harvard University and the University of Utah. Augmented reality (AR) is a field of computer research which deals with the combination of real world and computer generated data.
The system requires a special mirror to both reflect the projected image toward the cloak and to let light rays bouncing off the cloak return to the user's eye. This special mirror is called a beam splitter, or a combiner -- a half-silvered mirror that both reflects light (the silvered half) and transmits light (the transparent half). If properly positioned in front of the user's eye, the combiner allows the user to perceive both the image enhanced by the computer and light from the surrounding world. This is critical because the computer-generated image and the real-world scene must be fully integrated for the illusion of invisibility to seem realistic. The user has to look through a peephole in this mirror to see the augmented reality.
Augmented Stereoscopic Vision In Surgery
It allows the combination of radiographic data (CAT scans and MRI imaging) with the surgeon's vision. Doctors performing surgery could use optical camouflage to see through their hands and instruments to the underlying tissue, thereby making the complicated surgeries a bit better. Surgeons may not need to make large incisions if they wear gloves that project what's on the inside of a patient using a CAT scan or MRI data.
Cockpit Floors
Pilots landing a plane could use this technology to make cockpit floors transparent with micro reflectors. This would enable them to see the runway and the landing gear simply by glancing down. Hard landings would be a thing of the past if pilots could gauge how far they are above the ground just by looking at an mage of the outside terrain projected on the floor. This allows them to avoid many obstacles on the path below and be aware of the floor below them thereby creating a complete awareness.
Transparent Rear Hatch
Drivers backing up cars could benefit one day from optical camouflage. A quick glance backward through a transparent rear hatch or tailgate would make it easy to know when to stop.