Little old Lady
Little old Lady
this was a test of r/g laser from Holomaker, on Geola Polymer , viewed under laser light
Re: Little old Lady
Is is a two colour single beam Denisyuk?
If it is, then it is impressive. With AgX it is difficult to reconstruct volume holograms with laser light.
If it is, then it is impressive. With AgX it is difficult to reconstruct volume holograms with laser light.
Re: Little old Lady
Yes single beam Denisyuk
Re: Little old Lady
Is it sensitive to angle of ilumination?
A common AgX volume hologram (Denisyuk type) illuminated by white light changes its color as the illumination angle changes. It is thus very sensitive to illumination angle for laser illumination - it either reconstructs well, or does not reconstruct at all.
But I have no experience with laser illuminated photopolymer Denisyuks.
A common AgX volume hologram (Denisyuk type) illuminated by white light changes its color as the illumination angle changes. It is thus very sensitive to illumination angle for laser illumination - it either reconstructs well, or does not reconstruct at all.
But I have no experience with laser illuminated photopolymer Denisyuks.
Re: Little old Lady
Depending on the bandwidth, if a Denisyuk is laser illuminated, then the image will vanish over a range of about 5 - 10 degrees. This is because when you twist the Bragg planes, the illumination is off-Bragg. With no other wavelengths in the reconstruction, no other wavelengths will become on Bragg for a narrow band set of planes. According to Kogelinik, you can still reconstruct over a range of about δθ = 5 deg and about δλ = 5 nm. The dephasing parameter, ξ, can allow a small range with lower efficiency.lobaz wrote: ↑Sun Sep 13, 2020 2:29 am Is it sensitive to angle of ilumination?
A common AgX volume hologram (Denisyuk type) illuminated by white light changes its color as the illumination angle changes. It is thus very sensitive to illumination angle for laser illumination - it either reconstructs well, or does not reconstruct at all.
But I have no experience with laser illuminated photopolymer Denisyuks.
Photopolymers are necessarily narrow band because they don't need wet processing. That's the advantage of polymer for technical holograms, but a bit of a disadvantage for display holographers.
Re: Little old Lady
Nice work with the photopolymer, I found it more difficult to use it for RGB work than Agx.
In my experience, the reconstruction of volume Agx color holograms using RGB laser light is not difficult but the angle of illumination is likely to be different from the recording angle due to emulsion shrinkage, if any, and narrow like Din said.
Here is an example of my RGB Denisyuks reconstructed with RGB laser ligth: https://www.youtube.com/watch?v=BW12ktp8LmQ
In my experience, the reconstruction of volume Agx color holograms using RGB laser light is not difficult but the angle of illumination is likely to be different from the recording angle due to emulsion shrinkage, if any, and narrow like Din said.
Here is an example of my RGB Denisyuks reconstructed with RGB laser ligth: https://www.youtube.com/watch?v=BW12ktp8LmQ