Sorry Al, but the more I read your posts the more worried i'm becoming. You're talking about potentially using a 350mw laser in a small room to audience scan. There is no way on this earth that you are going to get enough divergence on those beams to ensure audience safety at such close proximity to the laser. You *MAY* be able to increase the divergence with some external optics assembly (such as a negative lens) BUT that's still waaaaay to much power at such a close distance. You really do need to look into this much more, I work in optics and am very aware of the fact that you only get one pair of eyes to last you a lifetime!!
Can I respectfully make a suggestion, for your benefit AND the benefit of all those poor people who will be on the receiving end of your laser show? Contact James Stewart (or his wife Julie) at Laservisuals and book on one of their laser display safety courses. This will give you an insight into how to calculate MPE's and ensure your audiences safety. You also mention scanguard, this is also marketed by Laservisuals, perhaps you could also find out what this software 'really' does. Oh, incidentally, if it's the 'Scanguard Lite' free version you're after, there's quite a few of us that are still waiting for it after many many months so I wouldn't hold your breath
Again, I don't wish to sound harsh but I think you need to perhaps research things a little more. Done correctly audience scanning is one of the most beautiful and crowd pleasing effects. Done wrongly and you risk being sued to hell and back for burning the retinas of all those party guests, and that's to say nothing of all the adverse publicity that will ruin things for all of us.
Cheers
Jem
Quote: "There is a theory which states that if ever, for any reason, anyone discovers what exactly the Universe is for and why it is here it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another that states that this has already happened.”... Douglas Adams 1952 - 2001