Contents• What is Holography
• Why Holography
• Types of Holograms
• How Holograms work
• Recording of hologram
• Reconstruction of hologram
• Advances in technology
• Applications & Future scope
• Conclusion
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What is holography
Holography is a technique that allows the light
scattered from an object to be recorded and later
reconstructed.
The technique to optically store, retrieve, and process
information.
Preserve the 3-D information of a holographed
subject
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Why
holographic display
A high resolution three
dimensional recording of an
object
Glasses free 3D display
No need for projection screen
Life like images
Interactive display
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Types of
HologramsA. Reflex hologram
Illuminated by a spot of
white incandescent light
source, from front-above
The image consists of light
reflected by the hologram
Produces multicolour
holograms, makes images
optically indistinguishable
from the original objects
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B.Transmission hologram Viewed with laser light, usually
of the same type used to
make the recording
Need light source behind them
Virtual image can be very
sharp and deep
C.Computer-generated holograms
No need for a real object
Interference pattern is
calculated digitally, using
algorithms
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How
holograms
workThe time-varying light field
of a scene with all its physical
properties is to be recorded
and then regenerated.
Hence the working of
holography is divided into
two phases:
•Recording
•Reconstruction
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Recording
of hologram Basic tools required to
make a hologram
includes a red lasers,
lenses, beam splitter,
mirrors and holographic
film
Holograms are recorded
in darker environment
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• Laser : Red lasers, usually helium-neon (HeNe) lasers, are
common in holography. These are coherent light source.
• Beam splitter: This is a device that uses mirrors and prisms to
split laser beam of light into two beams.
Object beam (directed onto the object) and
Reference beam (travels directly onto the recording
medium)
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• Mirrors: These direct the beams of light to the correct
locations
• Holographic film: Holographic film can record light at
a very high resolution, which is necessary for creating
a hologram. It's a layer of light-sensitive compounds
on a transparent surface, like photographic film.
Eg: Silver Halide Emulsion
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Process
When the two laser beams reach the recording
medium, their light waves intersect and interfere with
each other. It is this interference pattern that is
imprinted on the recording medium.
Hologram
Recording
Hologram
Recondtruction
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Reconstruction
of hologram
The photographic plate
is illuminated with
original light source used
for recording holograms.
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Capturing of
holographic
video By replacing the
conventional
holographic plate with
a digital camera and an
optoelectronic 2D
screen, we can
capture and display
holographic video.
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Projection of
holographic video
Video hologram is coded
into light modulators
These light modulators are
illuminated by coherent
light beam source, to
project video
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Advances in
technology Touchable holograms
Tactile holographic
display with haptic
feedback
Horizontal 360º view of a
image on table top
User interfacing
integrated displays
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Applications
& Future scope Educational applications
Marketing with 3D holographic
display
3D simulation displays for
scientific visualization
Improved virtual Reality and
augmented reality
Telepresence and video
conferencing
Entertainment displays
Military and Space Applications
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Holographic checkpoint
for military, battlefield
simulations
Intense real gaming
rooms
In future all displays like
televisions, mobile phone
displays, projector
displays will be replaced
by holographic displays
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Conclusion Holographic Technology
and Spectral Imagining has
endless applications, as far
as the human mind can
imagine
In future, holographic
displays will be replacing
all present displays in all
sizes, from small phone
screen to large projectors
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• “Holographic Projection Technology: The World is Changing.”;
Ahmed Elmorshidy, Ph.D
JOURNAL OF TELECOMMUNICATIONS, VOLUME 2, ISSUE 2, MAY 2010
• “Capture, processing, and display of real-world 3D objects using
digital holography”; Thomas J. Naughton; 2010 IEEE Invited Paper
• “Touchable Holography”; Takayuki Hoshi;
The University of Tokyo; 2009
• “Holographic 3-D Displays - Electro-holography within the Grasp of
Commercialization”; Stephan Reichelt, Ralf Haussler, Norbert Leister,
Gerald Futterer, Hagen Stolle and Armin Schwerdtner (2010)
• “How Holograms Work.”; Wilson, Tracy V. 2010.“ HowStuffWorks, Inc.
Downloaded November 05, 2010.
<http://science.howstuffworks.com/hologram.html>
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