Hi,

I have seen toy laser kits with as many as 48 diffraction caps that produce patterns from a line made of dots to even text that says "Happy Birthday" etc.

1) How is this done?
2) How can I make my own patterns?

After a bit of thought I tried a laser on a few CDs and got varying patterns. Maybe it's possible to burn certain data to create custom patterns? If so, how? (Maybe I should ask that question on a computer forum!) It seems like Yamaha used to have a burner that could burn images on the data side of a CD, called "DiscT@2" - obsolete since 2003. Are there any other ways?

A company that make such diffraction gratings for professional laser light shows are:

http://www.laservisuals.com/gratings.htm

I'm looking to create similar effects on the cheap.

Cheers