FIFTEEN
Don K.'s Laser Page
Get a laser pointer or laser diode module and not just a diode!
Beam divergence and use of lenses
Wavelength, color, and visibility.
Availability of non-red laser pointers and diodes
Links! Sam Goldwasser's mighty Laser FAQ, Craig Johnson's NEW laser pages, and more!
Power boost hacking of cheap laser pointers!
Laws and Regulations
Most recent update in Sam Goldwasser's laser FAQ (see links) I checked on 4/14/2008. Most recent update otherwise 4/14/2008.
Get a module or a complete pointer and not a bare diode!
Please, save yourself a few tons of trouble and get a laser pointer or laser diode module from someone who has already taken the time and trouble to get those infamously fussy laser diodes to do what you probably want.
Go here for a partial list of suppliers of working diode lasers. (updated 7/5/2003) These are getting really cheap - some around $5 and a few for even $1 - and are now the way to go if you just want a laser to play with.
If you already have a separate or bare laser diode (as opposed to a "module" which is ready to connect to batteries), please return it if possible. They are easily ruined. Complete laser pointers are now available at impressively low prices!
Laser diodes are rather fussy. The "junction" or main light-emitting working part of a typical laser diode is about the size of a bacterium and can overheat within a microsecond if its limits are exceeded. Furthermore, the minimum current to achieve laser operation ("laser threshold") can easily be near or over 80 percent of the "fatal dose" of current.
The light-emitting area of a laser diode typically emits more light than a similar area of the surface of the sun. Since more power must go into this area than into a similar size piece of the sun just to get things working at all, it should be understandable that things can easily go wrong.
Laser diodes can...
