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By "index-matching", I don't mean putting the whole set-up in fluid. :o I mean using index matching oil to put a cover glass in contact with the emulsion of a silver-halide transmission master. The intermodulation noise caused by too low of a beam ratio is composed of relatively low freque...

I don't think I've ever used a beam ratio for a pictorial volume phase transmission hologram less than about 5, for any material, and that was only with index-matching the hologram to reduce the noise. I think one would see quite a bit of intermodulation noise at lower beam ratios, and certainly wit...

I agree the ratio for the H1 is unrelated to the ratio for the H2. For the H1, the reference light should be about 10x the object light, at the recording plane. For the H2, the H1 is the object. I recommend starting with a reference about 2x the object light, again at the recording plane. You'll adj...

As much as I love holographic artwork, there doesn't appear to be much investment value in it. Consider those who bought works done in the late '80s. Probably be lucky to find a single buyer at 1/10th the price paid then. Nothing against the artists personally, and I'd love to have some of that work...

That's why a toilet seat costs $400, and why I don't work there.

Kyodal makes good points above, but I don't agree. The wearing of safety goggles all the time when working with laser light, just so they will be there if a beam ever hits you in the eye is neither practical nor a good idea. The first step in preparing a room to work with laser light is to provide f...

I seldom use goggles when working in holography. With green light, I generally use a beam attenuator right in front of the laser to turn the power down to a comfortable level for working with it. I'll wear goggles to look at and center the expanded beam if necessary, when the beam is at full power. ...

If you're parabolic collimating mirror is being used off axis, I'd be careful with your measurements. If off horizontally, measure the height of the collimated beam in the center of it. Make that constant over distance. Use exactly the same off axis tilt and the same mirror when replaying a transmis...

Don't read this one Jeff! Use a hacksaw to cut off an old objective as above, drill it out some way, paint it black inside, and glue the new one in place. Do a neat job (file after hacking) and it'll look AND work good as store bought.

The fringes don't actually "exist in space" if by that you mean there are a series of dark and bright spots in space. What actually exists is an oscillating electric field vector with a particular amplitude. If a material is placed in a space where the E-field is low, then there is not a ...