Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!bloom-beacon!bu-cs!purdue!decwrl!labrea!glacier!jbn From: jbn@glacier.STANFORD.EDU (John B. Nagle) Newsgroups: sci.electronics Subject: Re: Hobby laser show system Message-ID: <17883@glacier.STANFORD.EDU> Date: 7 Dec 88 01:22:17 GMT References: <2110@puff.cs.wisc.edu> Reply-To: jbn@glacier.UUCP (John B. Nagle) Distribution: na Organization: Stanford University Lines: 14 The low rent approach to this problem is to glue a mirror to the cone of an old loudspeaker. You can produce interesting but not meaningful patterns in this way. A setup with two mirrors, one for X and one for Y, allows positioning. Connection to a pair of D/As with DC-coupled power amps provides computer control, or connection to an audio system provides decorative patterns. Don't expect much precision. The high rent approach is feedback-controlled mirror galvanometers from General Scanning Corporation. These have a mirror, a galvanometer movement, and a variable capacitor for position feedback. This is how the laser-show people do it. John Nagle