Holographyforum.org / holowiki.org

more tidbits:

http://arstechnica.com/news.ars/post/20 ... splay.html

Avoiding electrical breakdown with 9 kV acoss a thin polymer film might be tricky...
Some commenter said that the write laser was about 100W - don't know if that's true. Will check the paper.

The original paper you have to buy from Nature of course, but the supplementary videos are freely viewable:


http://www.nature.com/nature/journal/v4 ... 06596.html

Be prepared to go to sleep while the whole recording and erasing procedure is shown. The authors won't win an oscar for editing!

I am struggling to work out what the main invention is here. Clearly the recording material is very interesting and I think that is the main invention. Recording seems to be similar to other integral techniques. I will try to get the paper to work it out.

Unfortunately the old cliches are out. See more crap here about holographic TV being just around the corner:

http://www.theherald.co.uk/features/fea ... he_way.php

Hi Kaveh -

In my understanding, this is primarily an ongoing improvement in a materials process. According to the article, they record hogels from an object beam (modulated by an SLM) and a reference beam onto a moving sheet of their material, while about 9 kV is asserted across it during write.

(Also it's nice to see that Pierre St. Hilaire is continuing to work on holographic video.)

The University of Arizona has generated some press releases around this, as well:
http://uanews.org/node/18022 (descriptive story)

http://uanews.org/node/18073 (movie with holograms)

-g

Yes, I agree. I think the main point is the material. I got hold of the article (if anyone wants to have a look email me - kaveh at holographer.org).

I can't see anything new immediately in the recording. I think it was put in just for PR. My guess is they found this material then wheeled in people to build an automated machine for integral holograms. Then they have a real 'story' with all the part!

The material is very interesting. Up to 90% DE. Not sure what the sensitivity is.

Nice to see you are also cited, Greg.

Hah! Thank you.

-g

The film thickness was 100 um. The 9 kV is probably just marginally short of the breakdown voltage for a polymer
film of this thickness.

The exposure was typically 1 second at 1W/cm^2 (for 70% DE) and the plate was 10x10 cm, so at least a 100W
532 nm laser would have been required. Erase time was much slower - a couple of minutes.

I guess that the real invention here is: a large format erasable phase hologram.

Unfortunately the sensitivity is very disappointing.

According to the article,

The use of HPO recording helps in significantly reducing the number of hogels in a 3D display, resulting in shorter total writing times. We have recorded 3D displays (4 x 4 inches in size) with complex and high-quality images within a few minutes using HPO imaging. (...) The total recording time used per hogel (0.8 x 101 mm in size) varies from 0.5 to 2 s, and the total irradiance (sum of both beams) used is 0.1 W cm^(-2).

The article also refers to tasks that they tested at various irradiances, such as 100 mW cm^(-2) and 1 W cm^(-2).

-g