From a purely consumer perspective, holographic display technologies have taken a back seat to other more mainstream advances like flexible OLEDs and laser-based projection. But even though you can’t watch NFL games on a holographic display, there is a strong community of scientists, engineers and even artists who are pushing the technology of holography and its uses. If you’re interested in AV technology, having even a cursory understanding of holography is valuable, and it may inform how you see other AV technologies you are working with every day. At the very least it will make you more interesting to talk to at your next AV cocktail party. Your first homework assignment: check out some holographic art. It’s typically interesting, expressive and poses challenges to artists as a medium.
If you live in New York City or find yourself in the area over the next month, go check out a new installation at the Center for the Holographic Arts (Holocenter). The art exhibition, Interference: Coexistence, will be curated by Holocenter’s director Martina Mrongovius, PhD. It opens tomorrow, Sept. 6 at the Clock Tower in Long Island City and will run until Sept. 28. It will feature the work of 25 holographic artists from around the world, including new holograms created from digital content.
Once you’re convinced holography is an interesting display technique, I’d encourage you to dig a bit deeper on the underlying scientific principles. Holographs are fundamentally different from traditional photographs because they record the phase and amplitude of light rays that are reflected from an object onto a holographic plate. Traditional photographs record only the amplitude of light reflected from objects in front of the camera. Objects that are illuminated by a coherent reference beam from the scene along with a beam of light that reflects from the object (the object beam) causes interference between the two light wavelengths at each point in the scene. As this interference, a pattern is reflected back to a measurement device and is recorded. This recording is captured as a pattern of tiny interference fringes. Each fringe can be smaller than one wavelength of the light used to create them and holds information about how the original object, when illuminated, will appear from all directions. In order to “decode” these interference fringes, it simply needs to be illuminated by a reference light source.
I won’t go into all the details here, but I will suggest a book that is my favorite introduction to the science and art of holography: “Holography Projects for the Evil Genius.” If you really want to make a splash at your next AV get-together, then this book will surely give you some ideas about how to amaze and impress your peers with some do-it-yourself holographic projects of your own. Good luck!