[attachment=2354]
[attachment=2355]

OPTICAL CAMOUFLAGE - Invisibility Cloak.

What is Optical Camouflage?
Itâ„¢s developed by scientists at the University of Tokyo.
Optical camouflage is a kind of
camouflage in which one wears a cloth
which projects the background so that he
appears somehow invisible.


What is Invisibility Cloak?
The invisibility cloak renders the human partially invisible, when he/she slips

beneath the shining, silvery cloak.

How Invisibility Cloak is Real?

Optical camouflage requires a complicated arrangement. First, the person who wants to

be invisible (Person A) wears the cloak. An observer (Person B) stands before (Person

A) at a specific location. At that location, (Person A) appear to be partially

invisible to (Person B). If (Person B) were viewing from a slightly different

location, he would simply see (Person A) wearing a cloak.


The Invisibility Cloak

The cloak that enables optical camouflage to work is made from a special material

known as
retro-reflective material.

Principle :

Optical camouflage doesn't work by way of magic. It works by taking advantage of

something called augmented-reality technology.

Augmented Reality :

Augmented reality merely tries to supplement real world with additional, helpful

content.

Requirements :

A garment made from highly reflective material
A video camera
A computer
A projector
A special, half-silvered mirror called a combiner

Video Camera :

Capturing the background image requires a video camera, which sits behind the person

wearing the cloak. The video from the camera must be in a digital format so it can be

sent to a computer for processing.

Computer :

All augmented-reality systems rely on powerful computers to synthesize graphics and

then superimpose them on a real-world image.
Computer :
For optical camouflage, the Computer must take the image from the video camera,

calculate the appropriate perspective to simulate reality to be projected onto the

retro-reflective material.

Projector :

For optical camouflage, the central opening must be the size of a pinhole. This

ensures a larger depth of field so that the cloak can be located any distance from

the projector.


Combiner :
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.

The combiner allows the user to perceive both the image enhanced by the computer and

light from the surrounding world.

Real World Applications

Pilots landing a plane could use this technology to make cockpit floors

transparent. This would enable them to see the runway and the landing gear simply by

glancing down.

Doctors performing surgery could use optical camouflage to see through their

hands and instruments to the underlying tissue.
Providing a view of the outside in windowless rooms is one of the more

fanciful applications of Optical Camouflage.
Drivers backing up cars could benefit one day from optical camouflage. A

quick glance backward through a transparent rear would make it easy to know when to

stop.

Disadvantages :

Surface is used as the reflector will be having the natural folds and

wrinkles in the material.
The target can only be in a certain field of view
Partial Invisibility
Requires Expensive Equipments.

Conclusion :

Although this is having some disadvantages, Optical Camouflage is a nice technology.

However further developments are being going on. I believe this is going to change

the entire world.