So yes, you're going to need good stuff to start with. Have you discovered Laser Pointer Forums yet? http://laserpointerforums.com/ There is a HUGE amount of VERY good info up there (some of it from me!) - you can find what you need there, the forums are organized by - among other things - wavelength!
Be forewarned - we've got it MADE here on the Parallax forums. Laserpointerforums.com is like - I don't even know how to describe it - but there have been and probably still are absolutely EPIC flame wars that erupt over there that have nothing to do with the beams! A lot of personality issues and some very sensitive folks who blow up often. If you step carefully you can find resources there however that you couldn't find anywhere else. Lots of years of experience, ranging from some very creative and dedicated hobbyists all the way up to post-doctorial professors of quantum physics and optics...
Still researching what is out there. I'd like to go with a collimated beam, since I want to study the effects at various distances
You can use your cell phone camera to visualize the beam (but do so with your goggles). There shouldn't be much absorption with a pure white card.
The problem with adding optics for a laser with this kind of output is that you must keep them scrupulously clean. It would be best if you experimented with a lower wattage laser -- something <10 mW, and then when you discover what works, you can move the optics to the high power laser. Otherwise, in all the handling of the optics you can very easily crack or discolor the elements.
Could you post a picture of the diode you have? Or do you have the Web site you got them from? You might actually have some optics in there already, unless it's a bare diode, which doesn't seem likely from your description.
The fact that the burn through on the pen cap is rectangular says there's no beam-shaping optics. Ideally you want a nice gaussian dot, not a rectangle. Laser diodes naturally produce a rectangular beam because of the way the chip is cleaved inside, but the majority of the really nifty laser experiments need a shaped beam that's round, and includes virtually no nulls across the beam profile (so-called TEM00 mode).
Comments
Be forewarned - we've got it MADE here on the Parallax forums. Laserpointerforums.com is like - I don't even know how to describe it - but there have been and probably still are absolutely EPIC flame wars that erupt over there that have nothing to do with the beams! A lot of personality issues and some very sensitive folks who blow up often. If you step carefully you can find resources there however that you couldn't find anywhere else. Lots of years of experience, ranging from some very creative and dedicated hobbyists all the way up to post-doctorial professors of quantum physics and optics...
Happy hunting!
Dave
You can use your cell phone camera to visualize the beam (but do so with your goggles). There shouldn't be much absorption with a pure white card.
The problem with adding optics for a laser with this kind of output is that you must keep them scrupulously clean. It would be best if you experimented with a lower wattage laser -- something <10 mW, and then when you discover what works, you can move the optics to the high power laser. Otherwise, in all the handling of the optics you can very easily crack or discolor the elements.
Could you post a picture of the diode you have? Or do you have the Web site you got them from? You might actually have some optics in there already, unless it's a bare diode, which doesn't seem likely from your description.
The fact that the burn through on the pen cap is rectangular says there's no beam-shaping optics. Ideally you want a nice gaussian dot, not a rectangle. Laser diodes naturally produce a rectangular beam because of the way the chip is cleaved inside, but the majority of the really nifty laser experiments need a shaped beam that's round, and includes virtually no nulls across the beam profile (so-called TEM00 mode).
-- Gordon