Holographic Hi Definition Display | Las Vegas Holography

LASER REFLECTIONS: WORK IN PROGRESS

By Ron Olson (Laser Reflections) - Revised on July 12, 2002

Holography Grows Up and Gets a Job

When was the last time you saw a quality holographic display in a high-end retail environment? Was it before or after you last saw a holographic sign in a trendy nightclub? If you answer the way most people do, then your responses are (chronologically):"I don't remember" and... "say what?" Holography may now have the dubious distinction of being something which - for most people - is entirely fictionalized: it exists merely as a fantasy prop for Star Trek producers unable to meet programming deadlines with credible story lines. Tooth paste boxes and credit card embellishments not withstanding - I'm betting you haven't had many opportunities to marvel at an honest-to-goodness hologram in some time (in the interest of good taste I dismiss the shrink-wrapped variety). Assuming I'm right about your minimal exposure, it's because holography as a visual display technique is truly a classic underachiever: something with great promise (like gyrocopters in the 60's) but never quite getting past the experimental stage. Past failures behind us, we're now poised to make up for some lost time and the good news is that we believe holography - as it has evolved - will prove definitely worth the wait.

Before laying out the new blue sky business plan, let me digress a bit to get at the roots of what went wrong with the initial public offering. Holography failed for one simple reason: the images weren’t very appetizing. Put in biotechnical business terms: the prospectus was intriguing but the product failed in clinical trials. More chronological digressing: photography (way back when) went through somewhat the same product cycle. For a while in the mid-19th century, people would purchase any photogram (as they were first called) because the technology was so interesting - irrespective of the image content. Mercifully, cameras proliferated and found their way into enough competent hands until the element of gratuitous technology ("I'll buy it because it's a photogram") faded into obscurity and people eventually chose to purchase certain photographs for their visual and/or emotional impact.

Holography by comparison never really made it out of the lab so-to-speak - the price of a laser-imaging system was very expensive and cumbersome almost to the point of absurdity. Holograms produced were typically of subject matter that ranged from chessmen and printed circuit cards to toy animals and aliens: not a lot to get excited about after you've finished up with your third grade studies.

Picture of Woman's Back turned Three Quarter

The reason for the limited subject matter was the aforementioned stifling technology - the exposure times for holograms were on the order of from thirty seconds to a minute and the allowable fidgeting on the part of the subjects was on the order of tens of nanometers. To illustrate: flowers in a vase in a still room jiggle about considerably more than is holographically tolerable. I ask you how many photographers could we (would we) support if photographic subject matter was both a) rock rigid and b) portable (holography is inexorably tied to a studio setting). As if this wasn't enough of an obstacle, add the facts that c) holographic viewing angles are limited and d) the images are of a single pure color. Wow! Is it any wonder that the technique was relegated to obscurity?

So along about the time that dedicated holographers were looking for part-time jobs and/or recreational drugs, somebody decided they'd do something about the motion issue (actually about the exposure issue). They correctly reasoned that the answer to the problem would be to use a pulsed rather than a continuous wave laser. If, for proper exposure, you need to put 1Joule of energy on a given photo-sensitive film you can either: a) use a 10mW CW laser and a 100 second exposure (10mW x 100 seconds=1Joule or b) use a Q-switched laser delivering the same 1Joule of energy in 50 nanoseconds. This pulsed remedy sounded good but as pioneering holographers' luck would

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