2.  Hologram
 History
 How is a hologram created?
 How does a hologram work?
 What are holograms used for?
 What are the features of hologram?
 What is hologram structure?
 What are the components of a hologram?
 What are the advantages of holograms?
 What are the uses of hologram in the future?

3.  A hologram is a picture of a "whole" object, showing it in
three dimensions. We've all seen cheap hologram images
on credit cards and ID cards (where they help prevent
copying). Far more impressive are large holograms that
take the form of a ghostly 3-D moving figure that you
can walk around to see from all angles. Holograms were
invented in 1947 but only perfected after the invention of
the laser in 1960. Today they're used in such
technologies as compact-disc players and checkout
scanners, and holograms can be created of the inside of
live internal organs to permit doctors to examine the
organs in great detail. And soon televisions with
hologram technology may enable us to watch in "3-D".

5.  Dennis Gabor CBE FRS was a
Hungarian-British electrical
engineer and physicist, most
notable for inventing
holography, for which he later
received the 1971 Nobel Prize
in Physics. He obtained British
citizenship in 1934, and spent
most of his life in England

6.  A hologram is made by superimposing a
second wavefront ( normally called the
reference beam) on the wavefront of interest,
there by generating an a physical medium.

7.  So, how do holograms work? Holography is a
unique method of photography whereby 3D
objects are recorded using a laser and then
restored as precisely as possible to match the
originally recorded object. When illuminated
via a laser, holograms are able to form an exact
3D clone of the object and duplicate its
features.03-Feb

8.  Holograms can be used in healthcare to
visualize patient data. Ordinarily, doctors rely
on Magnetic Resonance Imaging (MRI) and
ultrasound scans to generate 2D images of
internal organs, with which they have to
imagine how the organs would look in 3D

9.  This technique is used to perform imaging of
multidimensional objects. Holography uses
hardware, software and more exotic types of
programming to create hologram image. This
technology records light scattered from an
object to present it in a 3D digital image.

10.  The images are true three-dimensional images,
showing depth and parallax and continually
changing in aspect with the viewing angle. Any
part of the hologram contains the whole image!
The images are scalable. They can be made
with one wavelength and viewed with another,
with the possibility of magnification.

11.  In the holographic plate, both the beams
combine and interference pattern will be
formed. This interference pattern is recorded
on the holographic plate. The three-
dimensional image of the object can be seen by
exposing the recorded holographic plate
[hologram] to coherent light. This is the
principle of holography.

12.  In simple terms, hologram technology is a
three-dimensional projection which can be seen
without using any special equipment such as
cameras or glasses. The image can be viewed
from any angle, so as the uses walks around
the display the object will appear to move and
shift realistically.

13.  Reflection hologram.
 Transmission hologram.

14.  Reflection holograms form images by reflecting
a beam of light off the surface of the hologram.
This type of hologram produces very high
quality images but is very expensive to create.
(ii) Transmission holograms form images by
transmitting a beam of light through the
hologram.

16.  A hologram is a physical structure that
diffracts light into an image. The term
'hologram' can refer to both the encoded
material and the resulting image. Martina
Mrongovius 'The Conqueror'

17.  Laser. Lasers are the main components in
holographic equipment, and produce the actual
images. The image color will depend on the type of
laser used to create the image. The most common
laser used for creating holograms is the red laser or
helium-neon (HeNe) lasers.
 Holograms can be used in healthcare to visualize
patient data. Ordinarily, doctors rely on Magnetic
Resonance Imaging (MRI) and ultrasound scans to
generate 2D images of internal organs, with which
they have to imagine how the organs would look
in 3D.08-Feb-2022

18.  It offers creation of multiple images on single
plate including 3D images.
 ➨Holographic technologies can be easily
combined with other technologies.
 ➨It does not require special glasses to view
and can be viewed from any angle.
 ➨It does not require any projection

19.  Today's holograms are more advanced and are
being used in medicine, surgery, space
exploration, and advertising. Technology is
sparking new opportunities for
communication, education, entertainment, and
more. Holograms have a lot of potentials to
impact society in the future.

20.  Moreover, in the holographic reproduction, we
use a digital conical lens instead of the other
lenses. By loading the phase of the conical lens
on the SLM and adjusting the focal length of
the corresponding colors, color holographic
projection of the real object can be realized
without chromatic aberration.

21.  Holograms are made by using lasers. The
reason that they use lasers instead of regular
(white) light is because laser light is "coherent."
What that means is that all of the light waves in
a laser beam are the same size, and vibrate at
exactly the