SCRATCH or ABRASION HOLOGRAMS

From Beatty, SPIE

I became aware of this magical optical imaging technique thanks to students in one of my last classes at the School of the Art Institute of Chicago. They showed me the pioneering work of William J. Beatty on-line, and it made sense, certainly in the light of noticing patterns of light that seem to be off the surface of machined or polished pieces. So take a look at the effect in a scientific journal as described by its master. (Photo above from this paper.)

Another authoritative resource on the topic is this YouTube, courtesy of Patreon. There you can see more examples of the craft and how to do it.

Will this craze ever catch on? It is time consuming to make one, but that master could be replicated mass production style, like the Star Wars imagery shown in the YouTube, available on a vinyl disc of Star Wars Greatest Hits. There may be other products I am not aware of, check it our for yourself.

The scratch hologram raises some interesting discussion amongst the holo-cogniscenti, like "is it really a hologram?" There is no optical apparatus involved to freeze light waves like the reference beam does to the object wave in conventional interference holography, but the abraded patterns bear more than a passing similarity to interfered ones, as they follow the identical geometry! Plus the scratch hologram requires a point source to reconstruct its image, just like the classical ones! So what do you think?