Well, it's really the availability of multi-wavelength lasers. When I started, all I could get in England about 1982 was a Rofin HeNe about 0.7mW. Heck, I remember Goldfinger say, "This is a laser Mr. Bond. It can project a spot on the moon. At closer distances, it can cut through solid metal" ("Do you expect me to talk?" "No, Mr Bond. I expect you to die!" Be-e-eautiful! I still rank 'Goldfinger' up there with 'Citizen Kane', 'The Third Man' and 'The Godfather'. But I digress) Anyway, when I got to college, around 1972, and we were covering Laser Theory, the professor brought out a tiny little thing that could barely show up as a dim red dot on a wall about 6 feet away. I thought to myself, "That can project a spot on the moon???" Today, lasers in the 450 - 690 range are easily available and I have a uv led for about 20 bucks! So, while colour holography should be and is far more than simply zapping something with three wavelengths, you can get quite a decent result if you do simply that - throw three wavelengths at something. I think that colour holography has a greater mystique attached to it than it's due.Joe Farina wrote: One thing seems certain: making color holograms is a lot easier than explaining or troubleshooting them!
Mark, I'd like to know what material you're using also.