Holograms That Don't Change Color As You Move

An anonymous reader sends this quote from Wired: "By harnessing the power of tiny waves dancing in an electron sea, Japanese physicists have developed a novel way to project holograms that don't change color when you move your head. 'In a conventional hologram, if you change the angle, the color changes,' said optical physicist Satoshi Kawata of Osaka University in Japan. 'Our hologram shows natural color at any angle you observe.' The researchers’ machine takes advantage of how beams of light trigger waves of activity in free electrons, unattached to any atom, arrayed on a metal surface. Called surface plasmons, these waves could be used to blast cancer cells and build ultra-fast computer processors. They also show up in medieval stained glass windows, where plasmons on flecks of gold suspended in the glass make the window change color as the sun sets."

Re:It's about time..

[ackthpt]

This is pretty cool though, if it's as good as they're claiming. Maybe soon we'll have genuine 3D equipment that doesn't require headache-inducing tricks to render 3D. I'd be all for that, it'd be killer!

Considering it requires a backlight, I'm not so sure it's very practical. Also, 230nm thick, the first hurled Jujube would puncture it. Also, that's not a very sharp image. I wonder if they can improve the detail with different materials or that's it.

Color changing is the exception!

[zalas]

There's nothing that requires a hologram to change colors as you change the viewing angle; it's just that there are many different techniques for generating holograms and the rainbow hologram happens to have been adopted widely in the commercial regime. Classic holograms were monochrome and required coherent illumination to see. The rainbow hologram is nice in that you can see it under white light, but suffers from color issues (obviously) and also only presents a three-dimensional view along one axis (try tilting your VISA card 90 degrees next time and the eagle should appear flat). I don't know if the exhibit is still there or not, but the MIT Museum in Cambridge had a really nice hologram exhibit with lots of different holograms. A bunch of them were full color and didn't have that rainbow effect.

This article does make me more curious about surface plasmons, however, since I hear that mentioned a lot nowadays and don't have a very good understanding of them.