Bayfol HX polymer

Holography related topics.
dannybee
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Joined: Tue Jan 06, 2015 10:29 pm
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Bayfol HX polymer

Post by dannybee »

how many here are using Bayfol HX polymer?
I believe I have found a way to shift it in both directions from green to yellow - red,
and also shifting in down red to green - blue
have others here try to shift play back?
jrburns47
Posts: 165
Joined: Mon Sep 14, 2015 2:48 pm
Location: Oyster Bay, NY

Re: Bayfol HX polymer

Post by jrburns47 »

Why not write it up?
dannybee
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Joined: Tue Jan 06, 2015 10:29 pm
Location: visalia
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Re: Bayfol HX polymer

Post by dannybee »

yes was thinking about that, was hoping to get a response of those hiding in their holo caves, afraid to share :) ... to wake up the dead...:) I know, I got it to work .... but so wish this group would return the way it was in the beginning ;)
jrburns47
Posts: 165
Joined: Mon Sep 14, 2015 2:48 pm
Location: Oyster Bay, NY

Re: Bayfol HX polymer

Post by jrburns47 »

Realistically, it won’t. Most still here using HX200 are doing commercial work, mostly HOEs, I suspect, and are, not unreasonably, concerned about “trade secrets” and some have NDAs about their projects. Others just aren’t naturally communicators or sharers - they ARE holographers afterall😂… Only a few, like you and me, have the time or inclination to fool around with it for curiosity and non-commercial pleasure. Regardless, there’s a lot of HX200 information “out there” if you’re willing to dig for it. Luckily, there are still, and have been, plenty of good sharers of holo info. Suggest that you write up your findings and set a good example😊.
Din
Posts: 402
Joined: Thu Mar 12, 2015 4:47 pm

Re: Bayfol HX polymer

Post by Din »

jrburns47 wrote: Wed Jan 12, 2022 3:36 pm Realistically, it won’t. Most still here using HX200 are doing commercial work, mostly HOEs, I suspect, and are, not unreasonably, concerned about “trade secrets” and some have NDAs about their projects. Others just aren’t naturally communicators or sharers - they ARE holographers afterall😂… Only a few, like you and me, have the time or inclination to fool around with it for curiosity and non-commercial pleasure. Regardless, there’s a lot of HX200 information “out there” if you’re willing to dig for it. Luckily, there are still, and have been, plenty of good sharers of holo info. Suggest that you write up your findings and set a good example😊.
There are very few "trade secrets" in technical holography, almost all of technical holography simply follows the laws of optical physics and optical engineering that go back a century or more, overlayed with the technical principles of holography and a little creativity; usually, it's nothing more than Maxwell's equations and principles of diffraction (over a century old), with the Kogelnik paper being the only modern addition to practices. All real HOE's are optical components that are part of, and have to be compatible with, some overall optical function. So, in almost all the cases of HOE creation, you have to have intimate knowledge of the accepted physics and engineering of optical holography to satisfy the parameters necessary for the part of the hologram to be compatible with the rest of the optical function. In our case, I had the mathematical and physics knowledge and Joy and the engineering skills. The only times I and Joy had to strain the old brains were commissions by one of the Microsoft scientists in their research dept, who gave us some pretty difficult technical problems. Generally speaking, you cannot talk of the application, but you can talk of techniques which are well-known. So, case in point, someone wants a lens with an f# < 1. Holographically, this is quite a challenge because the precision required for replay is almost impossible to satisfy, leading to aberrations. But, if you have knowledge of the aberrations (Joy and I wrote a paper on holographic aberrations) and you understand the thick lens formulae, you can devise non-obvious geometries which will create a lens with f# < 1 with almost no aberrations. At any rate, sometimes the results are published, and you're acknowledge for solving the technical issues involved with holography. Such was the case for our work on the research on AR's by the Microsoft research group as well as the work we did with Nitto Denko for their refreshable holographic material. No one was interested in how we accomplished the desired result, so long as we did accomplish it. So, when we were asked to make a lens/reflector at 450nm, with a 458 nm laser, we had to find a way to shrink the hologram, without aberrations, down from 457 to 450 (we did it). On one occasion we were asked to make a notch filter covering the entire spectrum from 750nm to 450nm on dcg - no easy task - with an OD > 3 and a bandwidth < 15nm! But, we found a way to do this. The client didn't ask how we accomplished this - it was more important that we did. But, I cannot say why we had to do this.

So, if Danny, or anyone else, wants to publish results, they're usually free to do so. There's usually nothing in the NDA's about publishing techniques. On several occasions I did ask if I could publish techniques and I was told I could, provided I did not give away applications.

Of course, if you're designing and recording an HOE under FISA rules, that's a different kettle of fish altogether!
Loic74
Posts: 51
Joined: Sat Aug 10, 2019 9:09 pm
Location: France

Re: Bayfol HX polymer

Post by Loic74 »

There are some papers out there on shifting the HX200 material. From what I recall it involves using various materials to laminate onto the HX200. One of those articles had a table listing material vs shifting
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