Holographyforum.org / holowiki.org

Petr, yes, some idea. In a Bragg reflection hologram, the efficiency depends on the modulation, which depends on the ratio, and the hardness of the emulsion, assuming proper exposure and development. But, the planes are sinusoidal. This means that if it's overexposed, or overdeveloped, then the sinu...

I worked at Applied in the early 80's (about 1982). As I recall, we used D19 with either a fixer without hardener and a ferric bleach, or no fixer and a dichromate bleach. It was pretty much the workhorse developer at the time. I'm afraid I don't remember the formulations, but I'm sure someone here ...

I think we were answering the wrong question. The question was: "If the efficiency is polarisation dependent, then why is it polarisation dependent?" The question was not: "Is the efficiency polarisation dependent?" First of all, any medium with an index n, is supposed to "s...

Petr, I assumed it was holographic, since this was posted in a holography forum. The Gaylord and Moharam paper shows that if you have a surface structure with an amplitude, a and a grating spacing d, then if a/d >~3, polarisation dependence arises. If a/d >5, then the surface structure becomes polar...

One other thing that needs mentioning is that there are people who have developed a vector theory of diffraction. In this situation, the efficiency is a vector function of the reconstruction beams, and, of course, you can now insert the polarisation state of the recon beam into the vector function. ...

It's not true that the efficiency of a grating is dependent on the polarisation of the reconstruction beam. There are two theories of holograms: thin holograms and thick holograms. The criterion for differentiation is the so-called Q parameter Q = 2π(lambda)t/(nd^2) where: lambda is the recording wa...

There are two possibilities I can think of: 1. The OH in the glycerine is cross linking the gelatin 2. The pH may be wrong, either too acidic or too basic. However, adding gelatin to glycerine is the basis of what's called "green plastic" or "bioplastic". So, the intent of adding...

In any source of light, there are a number of colours, the range of wavelengths. So, a source may contain all the wavelengths between 450nm and 630nm, and such a source would look white. It may just contain the wavelengths from 570 to 600, and this will appear orange. The range of wavelengths in the...

The Olson's: http://www.laserreflections.com/stock.html

Godhand wrote:Thanks Guys ... I have sent Kris an email. Is it possible to make human portraits with this medium?

Yes: http://www.jrholocollection.com/index.p ... ic-studios