Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!wuarchive!uunet!world!digex From: digex@world.std.com (doug e humphrey) Newsgroups: sci.electronics Subject: Re: Laser show controllers? Message-ID: <1991Jun9.141328.16410@world.std.com> Date: 9 Jun 91 14:13:28 GMT References: Organization: The World Public Access UNIX, Brookline, MA Lines: 43 What you want are called Galvonometers (galvos for short) and where to get them is easy; the number one supplier for such things as affordable (sort of) galvos is General Scanning located in Watertown MA. Their cheapest is something like $330 or so, scans only one axis (you use two of these together to get X-Y) runs around 20khz I think (doing this from memory) and settling time depends on the setteled accuracy that you need. Motors do not do this kind of stuff well, and they are no the technology that is employed. GS has the basic pattents of some special capacitive coupled techniques that allow for very low mass, fast reacting structures to move the mirror structure, and good control to make sure that you do not overshoot the position, etc. You are about to step off the edge into some pretty expensive hardware if you really want to get into this. A good galvo and control setup for laser shows is around $10,000 to start, and more than that for something that you would do a "real" show with. Note that this does not count the lasers! Build your own can save you some money, though what you build will not be up to the standards of the commercially produced gear in all likelyhood, but it takes a *lot* of time, and in the end there is just no such thing as building your own galvos that can perform to the point where they are usable in a laser show. GS locks their dumpsters up, because they know that there are people in the Boston area lurking around trying to get the old, broken, maybe out-of-spec galvos that they no doubt throw away. Not for industrial spying, but because some of us can not afford to pop real bucks for galvos for our lasers. By the way, what are you going to do for lasers? I might have a nice Spectra Argon for sale, pumps easily 100mw, I can give you plans for a good power supply, or you could buy from MKW and pay some real money! Good luck. Doug Humphrey