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Typically the creation of a hologram involves lasers and various other expensive equipment and materials. William J. Beaty figured out a low-tech way to create your own holograms using a simple abrasion technique that requires only a compass and a chunk of plastic. He came across the idea while walking through a parking lot, noticing strange hand prints that seemed to float above or deep inside the surface of polished car hoods.

The images were naturally-occurring holograms. The owner of the car had obviously polished the hood with a dirty mit, and the millions of particles of grit in the mit traced out millions of nearly-parallel scratches in the black paint. The particular hand motion had created a geometry of abrasion patterns which turn out to be nearly identical to the interference patterns which make up those embossed-foil Benton whitelight [holograms].

So how do you make one? All you need is a spanner (compass with 2 needles) and a chunk of hard plastic such as Lexan. For simple flat shapes, you just draw the reference shape below where you want the hologram to appear. Set the diameter of the spanner to an inch or two, put one of the points on the shape and score a small arc across the plastic. You then repeat this process for a bunch of other points on the shape, leaving a number of small arc shaped scratches. When you observe the scratches in the light, you’ll see a hologram of the shape that appears to float beneath the surface of the plastic.

The image above, from William’s site, is actually a stereo photo of one of his holograms. You can cross your eyes to see the effect. The cube that reflects from the scratches appears different based on the angle you view it.

The depth of the hologram is related to the width of the spanner, so you can actually create three dimensional holograms using the same technique. William’s FAQs have more details on doing this, as well as hints for creating opaque shapes that have other objects hidden behind them which are only viewable from certain angles.

Abrasion Holography – Link