When I was in high school, one of my science fair projects was on optical computers. I developed many theoretical devices and techniques to make that work (in theory). One of those techniques was making dynamic holograms by creating wave patterns in a crystal. I started with the idea of using sound waves traveling through the crystal, but then I decided that was too slow, so I modified that idea so that light interacting directly with the crystal created the necessary changes in the index of refraction.
Researchers at BYU and MIT announced their new holographic display that uses mechanical waves (sound) traveling through a crystal to diffract light. It’s the same idea I had, but they are using thin wires in optical channels cut in the surface of a crystal; I was just going to propagate sound waves from transducers located along the edges of the crystal (for my first iteration). Later, I decided to use lasers to do the same job inside the crystal. My purpose wasn’t to use it just for displays; I saw this as part of the processor and memory elements, too. That’s why I needed more speed than just the propagation of sound waves.
Thank you for sharing that. I have been following this type of technology
closely for a while – I’ve also made some holograms in high school and
took a holography workshop from Frank DeFreitas (actually flew out to PA to
do this).
Several other autosteroscopic displays also exist. Among these are the
obvious lenticular/parallax barrier (cereal box 3D, Nintendo 3DS),
microlens based (like lenticular but viewable both horizontally and
vertically) and electrically controlled holographic displays (they’re kind
of slow – I’ve never seen one in real life).
It’s too bad we no longer have a darkroom. I would love to set up/acquire
DIY or real optical table if anyone is interested in pursuing holography at
the space…
On a related topic, there is a DIY full-color hologram kit that was
kickstarted last year. I’m kind of mad at the founder for not sending me
my $10 reward (sample hologram), but it might be worth buying a kit and
experimenting:
Are you the same member who built his own vibration-isolated optic table? I haven’t heard from that member for a while.
I’m a big fan of Viewmaster. I make a lot of 3D photos, and I own a Pokescope for viewing parallel 3D images.
I had a vendor give a presentation on holography and his company’s holographic technology at the Grand Opening a few weeks ago. I video recorded it, but I haven’t put it online, yet.
It might be possible to put in a holography lab at the Space, but I don’t believe it would be ideal. Holograms are sensitive to dust and vibration, including noise vibrations. Ideally, they should be located far from automotive traffic (especially highways, like 35E) and foot traffic, never mind a lot of machine shop equipment. Besides, the Space is becoming cramped. So, I’m looking for another location that could be used for holography experiments.
I have demonstrated my Litiholo monochrome holographic kit a few times. I was disappointed to discover that my first hologram has faded until it has virtually vanished. I probably didn’t fix it sufficiently when I made it. Litiholo has offered a full-color holography kit in the past, but it apparently is not a regular item that they keep in stock. They are offering it, now, for $300; the monochrome kit costs $100.
ETA: I forgot to mention… This week is the week that Photonics West is running. The holography vendor mentioned that he would be at it this week. I would have liked to have gone, but I don’t have the time and money saved up, yet.
When I was in high school our physics class was sponsored by Indiana State University for setting up a hologram lab. We used a mobile chemistry bench that had a 1 1/2" thick granite top on it, put 4 lawn tractor inner tubes on top of that, and a 1" thick, corner reinforced plywood box that we filled with washed sand.
It worked very well and since we used red/infrared sensitive film we turned one of the closets into a dark room to shoot then develop the film and put up a green bulb to see by.
It doesn’t have to be too expensive to set up a table.
You can also experiment with motors, speakers, and mirrors to draw different patterns on the wall to visualize audio.
