If you look at an ice cube that has cracked just the right
way, you can see the rainbow-like reflection from a crack
whose width is just around the wavelength of right. We
have a freezer at work that is great at producing these,
for some reason.
The idea is a system to produce these cracks
in a
controlled manner in order to embed a picture (or a
message) in a clear sheet of ice. I'd like this to exist just
for the coolness value, but they could be shipped in
insulated, dry-ice packed containers and destroyed very
easily once read. They might also make really cool novelty
ice cubes since there would be no dyes or chemicals
involved.
This being my first 100% dream-inspired idea, I'm not sure
how to go about manufacturing something like this, and I
would welcome some ideas. Here's what I'm thinking so
far:
1) Sound Waves
Direct ultrasonic sound waves from different points in te
ice to meet at the right places to create microscopic
cracks to function as Bragg gratings
2) "Lasers"
Use a very cold sheet of ice shaped like holographic film
(perhaps doped with food-safe laser-sensitive dye) to
make a hologram in the traditional way. I imagine the
color shifts that would occur as the ice melts (and the
thickness of the gratings change) would be fascinating to
watch
3) Rainbow Holograms
Employ the technology used to stamp the holograms on
your credit card on aluminum foil on the ice itself (perhaps
freeze the ice on the rainbow hologram die)
Ideas...I need halfbaked ideas for getting this done!