Zebra holograms?

Martin_D · Post by **Martin_D** » Mon Jun 14, 2004 9:05 pm

just out of curiosity... does anybody know how they do it? they look just too good... simply some of the best holograms I've ever seen...

Kaveh · Post by **Kaveh** » Mon Jun 14, 2004 9:14 pm

I find they look good from a distance, but as you get closer the pixels become visible. They right each pixel individually. I am not sure of the detailed process.

Dinesh · Post by **Dinesh** » Mon Jun 14, 2004 10:23 pm

Very simply, they calculate the FT for each view from a paticular pixel, I believe. They then scan the entire medium row-by-row, column-by-column plotting the FT onto each cell for the view from that particular cell. I imagine the calculations must be immense! The FT is then plotted with the pixel as a boundary, ie the FT is plotted within the limits of the cell. I believe this is directly imaged onto a photosensitive plastic. There is no H1-H2.

Sergio · Post by **Sergio** » Mon Jun 14, 2004 11:23 pm

Dinesh wrote:Very simply, they calculate the FT for each view from a paticular pixel, I believe. They then scan the entire medium row-by-row, column-by-column plotting the FT onto each cell for the view from that particular cell. I imagine the calculations must be immense! The FT is then plotted with the pixel as a boundary, ie the FT is plotted within the limits of the cell. I believe this is directly imaged onto a photosensitive plastic. There is no H1-H2.

Printed on a photosensitive plastic? Or a photosensitive holographic polymer film? If such machine could print on with violet (405nm) the film could be VERY sensitive, is it a direct reflection hologram (1:1)?

What about the possibility of someone built this machine?:shock:

Dinesh · Post by **Dinesh** » Tue Jun 15, 2004 1:27 pm

I believe they said "light sensitive polycarbonate" whatever that means. The medium is black and, while I haven't examined it that closely, it doesn't seem to be backed by a black material but itself seems to be black ( http://triple-take.com/holo_photos/phot ... /zebra.jpg .) Of course they're not going to reveal their process, but I believe it's imaged directly.
There was a sort of funny moment at SPIE 2000 or 2001 when Mike Klug was showing off the (then newish) Zebra stuff at a holographers party. Yuri Denisyuk was there and asked a question to Mike. Mike replied, "Our lawyers tell me I can't reveal how we made it" and Denisyuk said, "I know how you made it but what I want to know is.." (I forgot the actual question). Mike then said, "I know you do, Yuri, but I can't tell you"
It brought up to me the whole ridiculous side of the patent/legal business that you couldn't tell a man of Denisyuk's stature something he obviously was well aware of because of a lawyer!