HOLOGRAMMYS

HOLOGRAPHS are so boring! When Madonna appeared on stage with The Gorrilaz – the unholy cartoon creation of Damon Albarn and Jamie Hewlett - we were all blown away, not just by her comfort with showing so much leg at her age, but also by the powerful illusion created by the Musion Eyeliner system, and most of us wondered if the time for holograms had arrived!

When the dust all settled, it turned out, much like the holograms in Scooby Doo mysteries: it was never there! The Musion Eyeliner uses a very old stage illusion known as “Pepper’s Ghost”. The illusion fundamentally directs the audience to look through glass which is angled at 45 degrees from the audience, then using a projection or reflection illuminates the glass with the “ghost” image. The Musion Eyeliner system uses a  LED projection on a lightweight film, so it can create vivid full color illusions over a very large area. The Gorillaz appeared to be with Madonna so convincingly, because her tandem performance had been pre-recorded, and she was also a digital projection.

One of the most popular and familiar uses of "Pepper's Ghost" is for the ghosts that millions of visitors a year sit next to at the Disney Parks' Haunted Mansion attraction. 

So… the Gorillaz and Madonna: not a hologram. So what is? A hologram is a stereoscopic image.  Holograms are recorded using a flash of laser light on the subject, and a simultaneous flash of laser light known as the reference beam is directed at the recording medium. Like so:

Boring, right? The idea is that the light records the three dimensional object, and can then be reconstructed by projecting exactly the same light, but does it happen when we record our message to Obi Wan? No! But, Holograms are everywhere; they are in all of our hip pockets. Hologram security seals are the most prolific use of the hologram, but those are tragically boring.
Never fear! Researchers at AIST have developed a hologram by focusing laser light which produces plasma excitation from the oxygen and nitrogen in the air, and a University of Tokyo research team has added tactile feelings to holograms using what they call “acoustic radiation pressure”. As dramatic as these advancements actually are, holography still slides so easily into side-show slight-of-hand, and ultimately: smoke and mirrors.

Holographs are boring because they are a document rendered completely in the handwriting of the author, so unless you are a reference librarian discovering a lost letter from Benjamin Franklin the whole holograph thing may not be for you. Try holography, which is the method of creating three dimensional images, or holograms which, it turns out, you can fake using stage tricks. Oh! But remember to throw in some acoustic radiation pressure… honestly.