FREE ESSAY ON HOLOGRAPHY

HOLOGRAPHY

Holography
While working to improve the resolution of an electron microscope, a brilliant man named
Dennis Gabor had developed a theory on Holography. This dates back to the year of 1947.
Dennis Gabor is a British/Hungarian scientist who created the word Holography from Greek
terms. He used the word holos, meaning whole, and gramma, meaning message." Gabor
characterized his work as an experiment in serendipity that was begun too soon. The next
decade brought about frustration in Holography because light sources available at the
time were not coherent. 
In 1960 a breakthrough came forth. The invention of the laser had pure and intense light
that was well suited for the making of holograms. Emmett Leith and Juris Upatnieks of the
University of Michigan both had realized that Holography could be used as a 3-D visual
medium in 1962. After reading Gabor's paper they decided to duplicate Gabor's technique.
Gabor's technique was using the laser and an off axis technique borrowed from their work
in the development of side reading radar. The outcome of this experiment was the first
laser transmission hologram of 3-D objects. The transmission holograms that Leith and
Upatnieks created produced images with clarity and realistic depth. The only issue was
that they required laser light to view the holographic image. 
The experimental work of both these men led to standardization of the equipment used to
make holograms. Thousands of laboratories and studios today possess the necessary
equipment. They are the following: A continuous wave laser, optical devices, such as,
lens, mirrors, and beam splitters which is used to direct laser light, a film holder, and
an isolation table on which exposures are made. 
Stability is an essential trait because movement as small as a quarter wave length of
light during exposures of a few minutes or even seconds can spoil a hologram completely.
The staple of holographic methodology is the basic of the off-axis technique. The
creation of a hologram is quite extensive. "A beam of laser light is visually separated
into two beams. One, the reference beam, is directed toward a piece of holographic film
and expanded (its diameter increased) so that the light covers the film evenly and
completely. The second (object) beam is directed at the subject of the composition and
similarly expanded to illuminate it (Vacca, 16)." The object beam carries information
about the location, size, shape, and the texture of the subject when the object beam
reflects off of it. "Some of this reflected object beam then meets the reference beam at
the holographic film, producing an interference pattern which is recorded in the light
sensitive emulsion (Vacca, 16)." The hologram is illuminated at the same angle as the
reference beam during the original exposure to reveal the 3-D image after the film is
developed. 
Another great experiment that occurred in 1962 was by Dr. Uri N. Denisyuk of the U.S.S.R.
He combined Holography with natural color photography. Natural color photography was
created by Nobel Laureate Gabriel Lippman in 1908. Denisyuk's approach produced a
white-light reflection hologram that could be viewed in light from an ordinary
incandescent light bulb. 
Dr. T.H. Maimam of the Hughes Aircraft Corporation developed the pulsed ruby laser in
1960. This laser system was unlike the continuous wave laser normally used in holography.
It emitted a very powerful burst of light that lasted only a few nanoseconds, which would
be a billionth of a second. It is possible to produce holograms of high-speed events,
such as a bullet in flight, and of living subjects by it's effectively freezing movement.
In the year of 1967, the first hologram of a person was made. It paved the way for a
specialized application of holography, which is classified as, pulsed holographic
portraiture. 
The first mass distributed hologram which was a 4x3 transmission view of chess pieces on
a board was contained in the 1967 World Book Encyclopedia Science Yearbook. Along with it
was an article that described the production of the hologram and the basic information
about the history of holography.
An advancement that was made in holography was a 05-watt He-Ne laser. "The laser was used
on a nine-tone granite table in a 30-second exposure to make the original from which all
the copies were produced (Fournier, 55)." Another major advance in display holography
occurred in 1968 with the help of Dr. Stephen A. Benton. Dr. Benton invented a
white-light transmission holography while researching holographic television at Polaroid
Research Laboratories. This type of hologram can be viewed in ordinary white light
creating a rainbow image from the seven colors, which make up white light. The depth and
brilliance of the image and its rainbow spectrum soon infatuated artists who adapted this
technique to their work and brought holography further into public awareness. Benton's
invention is especially significant because it made mass production possible of holograms
using an embossing technique. These holograms are printed by stamping the interference
pattern onto plastic. The resulting hologram can be duplicated millions of times for only
a few cents apiece. As a result, the publishing, advertising, and banking industries are
currently today using embossed holograms. 
Dennis Gabor was finally recognized for his magnificent work in 1971. Gabor was awarded
the Nobel Prize in Physics for his discovery of holography in 1947. Lloyd Cross
discovered what is called the integral hologram. He did this by combining white light
transmission holography with conventional cinematography to produce moving 3 dimensional
images in the year of 1972. "Sequential frames of 2-D motion-picture footage of a
rotating subject are recorded on holographic film (Fournier 56)." When looked at, the
composite images are synthesized by the human brain as a 3-D image. 
A great asset to the invention of holography was The Museum of Holography. The museum was
founded in 1976 in New York City as an international center for the understanding and
advancement of this new medium. Rosemary H. Jackson is the founder. It serves as the
focal point for the art, science and technology, as well as the world's foremost
holography exhibitor. 'One year later, the museum opened its Portrait Gallery of Famous
New Yorkers (Hol-o-fame) with Martin E. Segal, NY Commission of Cultural Affairs noting,
We congratulate the Museum. I can't think of anything that has happened in New York in
the arts in the last four years that is more symbolic of this great city than this
innovative, new, imaginative and enduring art form (Fournier 122).' 
Another great asset came about in 1977, the Museum of Holography's traveling exhibition,
Through the Looking Glass." It is based on its inaugural exhibition of the same name and
was opened in Toronto. The traveling show visited art museums and galleries, children's
museums and science & technology centers in the United States and abroad for well over a
decade. 
What magazine was the first to use a hologram? The National Geographic magazine was the
first major publication to put a hologram on its cover. The March 1984 issue carried
nearly 11 million holograms throughout the world. Another cover hologram illustrated the
feature article, The Search for Early Man" came out in November of 1985. The December
1988 National Geographic magazine featured the most aspiring hologram ever published in a
large-circulation magazine. "The entire cover was holographic: a globe on the front
cover, 3-D type on the spine, and an advertisement on the back. The front-cover hologram
was made using a pulsed laser with an exposure of about seven-billionths of a second
(Fournier, 84)." The making of the December 1988 National Geographic cover was a trip
worthy of the Society itself: 
Holographic artists have greatly increased their technical knowledge. They know the
discipline and now contribute to the technology as well as the creative process. The art
form has become international, with major exhibitions being held throughout the world. 
How is Holography made? There are many steps to this process. A hologram can be made not
only with the light waves of a laser, but also with sound waves and other waves in the
Electro-magnetic spectrum. Holograms made with X-rays or ultraviolet light have the
ability to record images of particles smaller than visible light, such as atoms or
molecules. "Microwave holography detects images deep in space by recording the radio
waves they emit (Fournier, 90)." The type of holography that uses sound waves to see
through solid objects is called, Acoustical holography. Holography's unique ability to
record and renovate both light and sound waves makes it a precious tool for industry,
science, business, and education. The following are applications used today: 
-  Double-exposed holograms (holographic interferometry) provide researchers with crucial
heat-transfer data for the safe design of containers used to transport or store nuclear
materials. 
-  A telephone credit card used in Europe has embossed surface holograms that carry a
monetary value. When the card is inserted into the telephone, a card reader discerns the
amount due and deducts (erases) the appropriate amount to cover the cost of the call. 
-  Supermarket scanners read the bar codes on merchandise for the store's computer by
using a holographic lens system to direct laser light onto the product labels during
checkout. 
-  Holography is used to depict the shock wave made by airfoils to locate the areas of
highest stress. These holograms are used to improve the design of aircraft wings and
turbine blades. 
-  A holographic lens is used in an aircraft heads-up display to allow a fighter pilot to
see critical cockpit instruments while looking straight ahead through the windscreen.
Similar systems are being researched by several automobile manufactures. 
-  Magical, totally unique and lots of fun --candy holograms are the ultimate snack
technology. Chocolates and lollipops have been transformed into holographic works of art
by molding the candy's surface into tiny, prism-like ridges. When light strikes the
ridges, it is broken into a rainbow of brilliant iridescent colors that display 3-D
images. 
-  Researchers at the University of Alabama in Huntsville are developing the sub- systems
of a computerized holographic display. While the work focuses on providing control panels
for remote driving, training simulators and command and control presentations,
researchers believe that TV sets with 3-D images might be available for as little as
$5,000 within the next ten years.
-  Holography is ideal for archival recording of valuables or fragile museum artifacts.
For example, the form of a 2300-year-old Iron Age man unearthed from Lindow Moss, a peat
bog in Cheshire, England, was recorded by a pulsed laser hologram for study by
researchers. A reconstruction model of the Lindow Man was made by the Forensic Science
Department of Scotland Yard. 
-  Scientists at Polaroid Corp. have developed a holographic reflector that promises to
make color LCDs whiter and brighter. The secret lies in a transmission hologram that sits
behind a LCD and reflects ambient light to produce a white background. 
-  The arrival of the first prototypical optical computers, which use holograms as
storage material for data, could have a dramatic impact on the overall holography market.
The yet-to-be-unveiled optical computers will be able to deliver trillions of bits of
information faster than the current generation of computers. 
-  Independent projects at IBM and at NASA's Jet Propulsion Laboratory have demonstrated
the use of holograms to locate and retrieve information without knowing its address in a
storage medium, but by knowing some of its content. 
-  To better understand marine phytoplankton, researchers have developed an undersea
holographic camera that generates in-line and off-axis holograms of the organisms. A
computer controlled stage moves either a video camera or a microscope through the images,
and the organisms can be measured as they were in their undersea environment 
The previous statements were those created by Michael Erbschloe and John Vacca. To create
an invention such as holography, a very brilliant brain was needed. The history of the
hologram has impacted our lives greatly today. With that in mind, there are many
companies, government agencies and others who are using holograms. Take a Connecticut
drivers license for example, it now has a hologram on it. This way it is much harder to
create fake identification driver licenses. The way technology has changed over the years
is truly an amazing thing to see. If great minds keep existing in the world, imagine what
we can have thirty or sixty years from now. Below you will see a diagram of a hologram
with all its components. Dennis Gabor sure was an exceptional Hungarian physicist and if
it weren't for him, we may not have holograms today. 
Bibliography
I. Erbschloe, Michael and Vacca, John. Holograms and Holography. Charles River
Publishing. New York 1999 Pgs. 1-676
II. Fournier, J.M. Holography: The first 50 Years. Springer Verlas Publishing. New York.
March 2001 Pgs 1-202