thanks for the answer...
I'm a newb to the DIY laser field... i just found (for the second time...) someting on the web called "sam's laser FAQ" and its quite a resource for a newb like me...
he explains in fairly basic terms for people of average education and such, a lot of stuff. I found it very helpful, and, it calms a lot of my wondering what kind of laser to buy.
apparently, common laser diodes re all more or less the same "under the hood", and the raw beam shape is described as "astigmatic". when he talks about collimation with common salvaged lenses, he talks about a x-axis and y-axis having different divergences... and a overall "elliptical" or "wedge" shape.
when he says that the x axis and y axis "focus" at different focal lengths, I take this to mean in reference to making a DOT, which is what 99% of laser DIY-ers seem to be doing...
the "basic" beam pattern seems to be roughly 10 degrees by 30 degrees... I suppose i can just "waste" the wider portions of the light, after running it thri the lens... by having it go thru a circular aperture...
but, i basiclly satisfied myself that i dont SEEM to need a "certain type" of laser diode... i just pick one in my chosen wavelength, and without the lens on it, the "raw" beam patterns are seeming to be similar...
I seem to get lucky for my application, it requires 800 to 850nm wavelength illumination, and this is a "native" laser wavelength... i hadnt known about the pumping, and that IR diodes were having stuff done to the beam outputs to MAKE the other colors... i have a better basic grasp of whats going on now, i *think* anywys...
but i'm lot more comfortable buying just about *any* diode module or pointer and tking the lens of and getting what i am looking for...
the guy talks about lenses salvaged from cameras and such, so, it must be common practice to use common glass lenses, not requiring ultra special lenses.
really, i dont think i'd be attempting this w/o this site... not many places to get DIY comfortable with laser diodes informally, to sort of "fiddle" with them.
after i get my IR illuminator working, i think i might try to make a "laser flashlight" in visible too, if only for sh!ts and giggles...should be BRIGHT and long battery runs for walking in the woods, if nothign else...