Moving holograms: From science fiction to reality

[Fredz]

A new type of holographic telepresence allows the projection of a three-dimensional, moving image without the need for special eyewear such as 3D glasses or other auxiliary devices.

[youtube]http://www.youtube.com/watch?v=kbk5_XEZ3DQ[/youtube]

"At the heart of the system is a screen made from a novel photorefractive material, capable of refreshing holograms every two seconds, making it the first to achieve a speed that can be described as quasi-real-time," said Pierre-Alexandre Blanche, an assistant research professor in the UA College of Optical Sciences and lead author of the Nature paper.

The prototype device uses a 10-inch screen, but Peyghambarian's group is already successfully testing a much larger version with a 17-inch screen. The image is recorded using an array of regular cameras, each of which views the object from a different perspective. The more cameras that are used, the more refined the final holographic presentation will appear.

The journal Nature chose the technology to feature on the cover of its Nov. 4 issue.

Source : EurekAlert!

[cybereality]

Ok this is cool, no doubt, but I am unsure if this is a real hologram. They talk about taking different pictures of the subject from different angles and stitching them together. This sounds more like lenticular-style multi-view displays than true holograms. Real holograms work by recording an interference pattern onto an emulsion. The pattern itself contains every possible angle within the viewport. There is no need to take multiple pictures from different angles, this is something else entirely. Unless they are somehow generating the interference pattern digitally from the photographs, that could be interesting. Its just not clear what the process is. But any progress in this field is a good thing.

[Fredz]

I've read some docs on the University Arizona website and I can say that these are true holograms. The process is exactly the one you described, they use an array of cameras to record the scene and a software to encode the information onto a fast-pulsed laser beam. Then they create an interference pattern on a photorefractive polymer with a reference laser to produce the hologram.

It's only monochromatic, not very precise and quite slow for now, but in the last 2 years they've made some good progress, from 30 seconds to 2 seconds for the recording and from 6" to 17" for the hologram surface. Let's see what they can achieve in two or more years...

[cybereality]

Ok, if thats the case then it sounds cool. They still have quite a ways to go though.

[BlackShark]

The thing I don't like about this video is that the professor is confusing his hologram (which needs a screen to support the picture) and the Star Wars hologram reference which is displayed in mid air without any screen.

And by the way : the RD2D princess Leia hologram is a 2D picture, not 3D. It was taken with just 2 cameras, one from the front (R2's camera) for the message and one from the back for when the 3po and the stormtroopers arrive in the room and interrupt her (just for the movie)

[Fredz]

Yes that reference to Star Wars was a bit unfortunate, but it was probably the best way for them to explain their technology in terms anyone can understand.

I've found another article which depicts the system's installation and presents some better videos :
http://www.bbc.co.uk/news/science-environment-11685582" onclick="window.open(this.href);return false;

[cybereality]

Yeah, he really didn't need to bring up Princess Leia. We're not there yet.