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Having done my first few photopolymer holograms (Bayfol HX200), it seems that polymer is more dependent on beam ratio equality (ideally ~1:1 for a reflection hologram) compared to DCG. It reminds me of silver halide, but perhaps not as extreme. Maybe this is due to the dyes present in polymer and s...

Yes, a 2f-2f geometry will create the real image on the other side. But, you have to consider aberrations, particularly coma and astigmatism. Coma will distort the image and astigmatism will cause a variation of the focus through the depth of the image. To avoid this, the lens has to be much larger ...

Given your extensive experience in creating and testing -- 1. Would you agree that UV light exposure is the biggest risk to black-backed SHG holograms? P.S. We found that UV filtering plexiglass did not impair our image reconstruction. 2. Do you agree with the Wise article's statement about heat ex...

There's no such thing as a zero divergence beam. Any plane wavefront would have to be infinite in extent to have zero divergence. Diffraction causes any finite plane wavefront to diverge: "Diffraction causes light waves to spread transversely as they propagate, and it is therefore impossible to...

... it is reasonably collimated. (But divergence looked rather substantial.) Joe Joe a laser cannot be collimated and have a divergence. The beam exiting the laser is always diverging because it's in the nature of the Gaussian profile (I can give you the mathematics of it if interested). There is a...

Thanks, Din, this paper is new to me, and I appreciate it. The paper is disappointing, because it's more of a "survey" of art, rather than a technical study. It did have an interesting list of potential problems with silver halide materials. I think this might be useful for the original p...

Joe Farina wrote: ↑Mon Jan 22, 2024 9:47 am Hi,

I think this would be a very interesting area of research. As far as I know, there has never been an independent and unbiased evaluation of the permanence or longevity of holograms.

http://resources.culturalheritage.org/p ... 5_Wise.pdf

Hi everyone, I am new to this forum and new to holography. I am planning to start with Denisyuk reflection holograms using a 5mw 650nm laser diode. Q1: should I opt for PFG-3m or the older PFG-1 plates to start with? Start with 01 Q2: is the recording / developing of PFG-3m more difficult than PFG-...

This is the program for the holographic part of SPIE West later this month in San Francisco. I'm particularly interested in the IR sensitive Bayfol to be given by the Covestro people. I was once asked to develop an IR sensitive holographic medium for eye tracking because of the interest in eye track...