Why Study Holography?

Frank DeFreitas Holography | Allentown, PA | Phone: 610-770-0341

Why Study Holography?

Publishing Notes
Updated 14 July 2011

Holograms in Art, Science, and Tech Education.

By Frank DeFreitas

Not since the earliest of cave paintings has a medium represented the world around us as accurately as holography. Holograms are not the first time we have been down the path of three dimensional imaging. It began through perspective painting, and moved on to depth through stereo or binocular recordings (either by hand, or later by photographic means). With holography, we have a method which captures the truest dimensional images of all time. It is both a communication art and a Nobel prize-winning science, with the most modern of technologies thrown in for good measure.

The Science of Holography
The science of holography begins with physics: notably light and optics. It was in 1971 that Dr. Dennis Gabor received the Nobel prize (in physics) for his invention of holography. Holograms themselves are a type of optical element that are created with the use of coherent light from lasers. When creating a hologram, one works with lenses, mirrors, beamsplitters, pinholes, and light-sensitive recording media. Chemistry is also involved through the development of silver gelatin film and glass plates. Other scientific disciplines include polarization, constructive and destructive interference, reflection, refraction, and coherence. Mathematics come into play when setting up the recording angles, taking beam path measurements, and calculating exposure times.

Holography in Communication Arts
As a tool for visual communication, holograms provide the ultimate in realism, and also in the abstract. With a hologram, two solid three dimensional objects can both occupy the same three dimensional space, at the same time. So situations that are not physically possible in the "real" world, are possible with holography. This certainly leads to some fanciful work by artists. Products can be depicted as if it were physically present, except that your hand passes right through the image. Full-color, computer-generated holograms are becoming better all the time, as computer processing capabilities increase. And true holographic television has been demonstrated on a small experimental scale. With the advent of diode lasers, more amateur and hobbyist holographers are now setting up their own hologram studios, very similar to the amateur and hobbyist photography boom of the 1950's, '60's, and '70's. While holograms on product packaging has declined in recent years, the use of holograms for product security and authentication continues to grow.

The Technology of Holography
Holography is the most technologically advanced science in the world. Especially computer-generated holograms that are written by calculating the three dimensional optical wavefronts that would come off of imaginary objects and scenes. Remember, 3D wavefronts must be calculated from every possible position of the viewer -- AND be reproduced in TRUE three dimensional fidelity. If it were possible to zoom in on a holographic object from afar, one would be able to resolve surface bacteria on that object. THAT is the resolving power of holography, and gives some indication of just how much information a hologram stores. From the precise manufacturing tolerances for diode lasers, to the surface coating of the most precise mirrors, at its upper end holography is truly the ultimate in futuristic media production.

If you want to study holography, you will find an entire universe of learning possibilities. You do not need to know everything about the science of holography in order to make a hologram. Just as you do not need to know the light-path mathematics behind your digital cameras optical system to take great pictures. Holography does, however, contain the potential to provide a little bit of everything, from the technical to the artistic. It is a great team activity, especially when combining science students with visual arts students. It allows for dialog between these two groups that normally does not take place in the workplace. But the best holographer of all is the person who excels in both the scientific and the artistic. This is the requirement of the future: to be the best you can be in both. Holography provides the opportunity to do just that.

-- Frank DeFreitas