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Holography Essay, Research Paper
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 4×3 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.
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
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