Holograms_in_Motion_Holographic_Films_Holographic_Television
4.3 Holograms in Motion, Holographic Films, Holographic Television
Three-dimensional cinema is already well-known, although we do have to wear glasses to get three-dimensional experience. So-called stereoscopic solutions try to imitate three-dimensional reality by means of special glasses separating the information for each eye. Thus we obtain twice as much information: the pictures which are seen by the right and the left eye. A real three-dimensional image contains a hundred times more information. This is the reason why, with the stereoscopic system some of the details, which we want to look at closer by moving our heads around, are hidden from us.
One of the best-known multiplex holograms is "Kiss II", a holographic stereogram, produced by Lloyd Cross, inventor of the process in 1974. This integral hologram, or holographic stereogram, combined white-light transmission holography and conventional cinematography to produce a moving 3-D image. The hologram – which was made from approximately 360 frames of motion-picture footage was typically mounted in a semicircular, wall-mounted display and illuminated by a single light bulb below. The floating three-dimensional image of a man blows a kiss and winks as the viewer walks by. Sequential frames of two-dimensional motion-picture footage of a rotating subject are recorded on holographic film and the composite images are synthesized by the human brain as a three-dimensional image when viewed. (Overton, 2005).
Authors of science-fiction novels like to describe the holographic film, where heroes get off the projection screen into the area among the audience. Prototypes of holographic films have been experimented since the 70s, scientists of leading Universities all the time have been working to create the releasable holograms.
The first experiments were realised in Russia. They recorded individual frames of motion pictures of holograms, copied them on holographic film and projected them on holographic projection screen. Actors were afraid of going blind, but the dispersion laser light is not harmful (Sedláček, 1982).
In September 1965, issue of Laser Focus reports the showing of a holographic movie. During a four-day government-sponsored Stanford Electronics Research Review Conference, a hologram motion picture recorded on 35-mm film was shown. According to Stanford, not only was this the first holographic motion picture ever produced, but it was also the first demonstration that laser holograms could be made on a continuous strip of film (Overton, 2005).
Optical technician Yves Gentet invented the portable holographic cine-camera to record the face complexion, holographic film and emulsion that he named Ultimate. Gentet colour holograms are created by transluminating laser light of mixed colours through the transparent holographic film onto the object (Kunzig, 2002).
Articles published in 2002 (Freedman, 2002) predicted that three-dimensional holographic video images will be generated by computer; they will be shown in full colour and with input from a user, changed on the fly. What’s more, viewers who move around a holographic video image will be able to see it moving from every side – a phenomenon important to realism (Kamys, 1999) and one that many conventional eyeglass-based systems cannot replicate.
Most doctors, scientists, researchers, and new product developers who already rely on sophisticated computers to display their works, are showing dramatic differences in this new technology. Currently, their work is constrained by the flat, two-dimensional images of conventional displays. No matter how cleverly the screens are dressed up, they can’t convey all the nuances, intricacies, and immediacy of real objects in the three-dimensional world. Because the new video holograms produce fully three-dimensional images that float in space near the viewing screen, they can be examined from different angles by multiple viewers. Geophysicists examining high-resolution images of rock formations will be able to predict the location of hidden oil deposits with greater accuracy. Industrial designers (Mihok, Vidová, 2005) will be able to modify a sports car’s body using the tip of a stylus, instantly generating the change’s effect on the overall design. Military commanders will be able to visualize the best battlefield scenario. Surgeons will be better able to determine the safest approach for removing a brain tumour without ever wielding a knife.
The question is when shall we have in our own living room three-dimensional video images projected without screen, when shall we watch without special glasses from any perspective without distortion and images be so true that you feel you can touch them with your finger.
In 2004 the scientists of Chiba University in Japan announced that they had developed a generator of holograms on a board with one circuit that generates holograms on LCD panel.
There are two important centres for research on holography: The first one is New York University’s Media Research Lab where teams are working on a less expensive version called 3-D auto stereo display, and the second one is MIT Media Laboratories where they have been from the beginning focusing on true holographic video, which not only keeps the promise of the highest-quality 3-D video images, but also provides the most daunting technical challenges (Freedman, 2002).
As early as 1989, the team of MIT Media Lab Spatial Imaging Group developed the visualisation medium – electro-holography – enabling to create true three-dimensional moving holographic images in real time. The follow-up research led to full-motion-colour images, synthetic images and real entry.
The MIT holographic video still requires much work before it can be commercialised. The most important problem is that the creation of video hologram requires the processing of an enormous volume of data, and therefore a number of compromises in image quality are accepted in order to reduce the computing requirements.
They also work on the project of "haptic" holovideo that enables the viewers to "sculpt" the holographic images by interacting.
The Light Biology Applications Laboratory Texas Southwestern have recently used the digital micro mirror device (DMD) Texas Instruments' Digital Light Processing for the development of digitally controlled 3D holographic projection in real time. The Laboratory finished the demonstration of the verification of the concept by means of computer-generated holograms.
Laser Magic Productions developed a family of 3D imaging technologies that offer the illusion of out of screen 3D projection. Tran Screen Transparent Video Projection Screen from Tran Screen is built from microscopic patterns of particles that will hide the images from viewers (www.laser-magic.com, 2006).
The screen was combined with Laser Magic's Laser Valve Video Projector (LVP) that shows the video images by using laser light instead of the light from xenon vapour lamps. A Projector was developed in connection with Laser Magic and JVC. Laser Magic suggests lower mass pictures that can be moved round the place of performance; laser technology in LVP gives the projector almost infinite depth of field without focusing (David, 2004).
Today, there exists a small-scale version of three-dimensional television in Dallas laboratory of Harold Garner, 51-year-old medical doctor, plasma physicist and biochemist at the University of Texas Southwestern Medical Center. American scientists developed the imaging technology that enables the viewers to enjoy what is said to be the first true three-dimensional holographic films. The prototype that was built by Garner is a machine that generates holographic movies – true 3-D without special glasses or nausea. The author said that he could see the technology being used for entertainment applications like 3D multiplayer games, theme parks, holographic cinema and holographic TV.
Naturally, the inner equipment of this device are unfathomably complex, but we can tell that it is based on complex optics principles, extremely clever computer programs, and a small chip in many mirrors. The device is made up of nearly one million reflective panels, each of which can be angled by a computer several thousand times per second to reflect or deflect beams of light, producing moving pictures.
Garner’s big idea was to blast the DMD (digital micro mirror device) with a laser rather than with a typical projection bulb and by the formation of various wavelengths with mutually shifted phases, he created the holographic effect.
He programmed the DMD to reflect a sequence of 2-D interference patterns (called interferograms) that disrupt the laser light in such a way that it reflects a 3-D hologram. Garner’s biggest challenge has been to find a suitable screen. To unfold the 2-D interference patterns into true 3-D images, the projection surface must have volume. So Garner is working with a display composed of layers of micro thin LCD panels. When the panels flash on and off in quick succession to assemble the hologram, the speed is more than sufficient to convince the eye that it’s seeing a solid object. Garner’s approach is the most viable solution for 3-D TV. The 3-D images are sent as a 2-D interferogram, which does not require any other bandwidth than today’s television signals, so we can use the current broadcast infrastructure. The first application of Garner’s technology may be in the holographic imaging for the military. Naturally, there are really useful applications for this technology that could really benefit mankind: holographic visualisations of human organs, dental and bone development, surgeon training and all that kind of things (Slocombe, 2005).
