HeCd lasers for holography?

[Jeffrey Weil]

Hello Bob,

The big potato masher from Kimmon is rated at 200mw@441.6mn. Beam shape and divergence are as good as your best He/Ne but little coherence. Only 15cm of usable space at most. 5000 hours. Since it's a Kimmon it'll put out full power for most of it's lifetime. The Liconix models from the past faded out more with time. Kimmon will burn strong until almost the end.

It's extremely expensive. Plus you might have to get some accessories for it at more cost.
Since it's a He/Cd it should be re-tubed by the factory (Japan) or at least the factory rep in the States, Patrick Townsend. That means expensive shipping and down time when you need a new tube. It'll require some more of the single isotope cadmium by that point so you can't just re-gas them like argons and kryptons. This is a metal vapor laser, not just gas.

It puts out enough heat that it needs to be piped out of the building for good holography and the case, which is 5 feet long, is pulling air from the bottom in a fashion that it could never be on the table. Most embossing labs put it in another room and drill through the wall for a way to get the beam onto the table and avoid it's heat.

It also requires an hour of warm up time for serious work.

It's not easy being blue.

One good thing is in the last few years they moved over to switching power supplies instead of the old transformer big iron ones. They weight much much less than 10 years ago. Only the supply of course, the gas laser itself hasn't changed much at all over time.

Jeff Weil

[Jeffrey Weil]

I forgot to answer the original posters question.

I've been shopping on ebay for various things and I keep seeing accessories
for HeCd lasers but I never see the lasers themselves.

The reason for that is mainly, but not only, the client base for this kind of laser. Most would be big budget places at universities and in industry. Like dvd mastering plants with 15 of them going 24 hours a day. Places like that don't sell things on ebay one at a time. Plus, they need them and will re-tube when they burn out.

Also, few people want them used.

The places that usually buy He/Cd's want them new. They need support and want new reliable equipment. Not things that are going to mess with their production schedules. Things they can buy right now, while the budget and need are there. Not after looking on ebay for months.

Jeff Weil