I want to do some experiments with CGH ... but doing it on the cheap seems almost impossible. The laser printer based CGH all rely on projection, while it's interesting to get a projected image out of a fringe it's not exactly 3D. Any low resolution methods will suffer from the fact that by the time you have put enough of an angle away from the laser (which you have to do, unless you really want to look straight into the laser most of which is undiffracted) there will be precious little viewing angle left.
You can get photoplots at 64K DPI which is practically half wavelength ... but those come at 100 euro a pop at 10"x12". Also I wonder if they would really take a 60 GB file for plotting.
What are the options?
CGH, are there any cheap options?
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JohnFP
CGH, are there any cheap options?
Making a stereogram of the differt computer views of the object would be one.
You could start with two views for a narrow viewing window, and increase the number of veiws for larger windows.
Frank DeFreitas has explained this for the beginner quite well. It may be under portraits. If you can't find it, let me know and I will search for it for you.
http://www.holoworld.com/
You could start with two views for a narrow viewing window, and increase the number of veiws for larger windows.
Frank DeFreitas has explained this for the beginner quite well. It may be under portraits. If you can't find it, let me know and I will search for it for you.
http://www.holoworld.com/
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MfA
CGH, are there any cheap options?
Autosterograms are cool ... but in the end you need almost as high a resolution as a hologram to capture a good 3D view if you want a decent viewing angle.
It always comes back to resolution. It's strange too, in theory you really don't need that much information to encode the object wave if you are willing to settle for say mm level detail ... just create a hologram with mm wavelength radiation and a hologram with a half mm line pitch. It works fine in the computer ...
It always comes back to resolution. It's strange too, in theory you really don't need that much information to encode the object wave if you are willing to settle for say mm level detail ... just create a hologram with mm wavelength radiation and a hologram with a half mm line pitch. It works fine in the computer ...
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MfA
CGH, are there any cheap options?
After having looked around, you can get substantial resolution increases with heat shrinking plastics (5 times along both dimensions in that example, much better than shrinky dinks). Also it is in possible to trade off spatial resolution against viewing angle with a fly's eye array (this is not the same as integral imaging, it's basically a hybrid).
The only problem is that all the consumer printer solutions with halfway decent resolutions are binary, which introduces unwanted diffraction orders ... not really a clue how to bypass this rather fundamental problem. Someone at MIT is working on shrink plastics with inkjet printing for holograms/gratings, but no publications yet :/
The only problem is that all the consumer printer solutions with halfway decent resolutions are binary, which introduces unwanted diffraction orders ... not really a clue how to bypass this rather fundamental problem. Someone at MIT is working on shrink plastics with inkjet printing for holograms/gratings, but no publications yet :/