invisibility .. how a person or thing can be invisible

1. Made possible

2. Ways to create
-manual way
-scientific way
Difference between manual way and
scientific way
Applications
Limitations
Conclusion
References
Outlines :

3. MANUALLY SCIENTIFICALLY

4. Manual Way
(just to mean literally “invisible”)

5. Just to mean literally “invisible”

6. A digital video camera captures the scene
behind the person wearing the cloak.
The computer processes the captured
image or video so it will look realistic when
it is projected.

7. The projector receives the enhanced
image from the computer and shines it
through the opening onto the combiner.
The silvered half of the mirror, bounces the
projected image toward the person
wearing the cloak.

8. The cloak acts like a movie screen,
reflecting light directly back to the source.
Light rays bouncing off the cloak pass
through the transparent part of the mirror
and fall on the user's eyes.

9.  In maual technique the observer needs
to look through a half mirror thus system
needs half mirror and projectors.
 So it’s a little bit slow as we have to
adjust and setup everything.

10. Scientific way
(deflecting microwaves)

11. By the use of metamaterials. Meta is
Greek word that means “beyond”.
The metamaterials means to create
something that doesn’t exist in nature.
Metamaterials are a class of artificially
engineered composite materials having
extraordinary electromagnetic properties.

12. • It can deflect microwaves around a
three-dimensional object.
• It can make the light bend in an
opposite direction from normal paths.
• It contains bits of metal or other
substances.
• Embedded in precise patterns.

14. • Due to negative index the net effect is of a
wave propagating in the reverse direction
of the light and energy flow.
• Metamaterial divert the incoming wave
arround the object preventing both
reflection and absorption.

15. MANUAL WAY SCIENTIFIC WAY
 Use camera to capture
image.
 Processes it to computer.
 Projected onto a reflecting
cloak.
 Relay on product called
metamaterial
 Metamaterial will
influence the EM wave
arround it creating a
“wrapped effect”.
 This create invisibility
effect.

19. • Solar panels coated with
metamaterials would be
more efficient than those
coated with conventional
black paint, which
reflects 5% or more of
incoming light.
• In military, invisibility
phenomena is used to
hide tanks, bunkers,
submarines.

20. • The invisibility effect work only for a specific range
of wavelengths. It operates only over a narrow band
of frequencies.
• The cloak could be made to cover a volume of any
shape, but you can’t flap your cloak. Moving the
material around would spoil the effect.

21. A lot of interesting thing have been done
and already we have seen that anyone can
be almost invisible with this technology.
Research work is going on and soon we
will have even more astonishing results.

22. http://news.discovery.com/tech/invisibility-
cloak-3d.html
http://science.howstuffworks.com/invisibilit
y-cloak.htm
http://www.washingtonpost.com/wp-
dyn/content/article/2008/02/19/AR2008021
902617.html