Hi everybody my name is Adam and I am a recovering flashaholic it has been 2 weeks since my last build. I have found that lasers are the only thing that seems to take my mind off flashlights unfortunately now they are the only thing on my mind. I have completed two laser build since starting this bad habit a month ago. My first a Dorcy Jr. with 16x Sony diode at 350ma with a flexdrive and a RCR123a. The second a pen light host with a PHR-803t Blu-Ray at 150ma with a RKCSTR driver and 2X 10440. The Blu-Ray came out great, small pen with a forward clicky in the back so you have momentary on and click to stay on. Unfortunately I couldn't leave it alone and decided it might need a spacer to keep a spring from touching the case. Of course I unknowingly knocked the pot off the board, so I banged the laser on my hand to fix it, didn't help in fact that might explain the bad driver and diode Anyways I ordered more PHR-803ts and will have enough parts to make several more but this time I'm using a flexdrive and 2x AAA. I also left my Dorcy on in my pocket for an hour so now I have a awesome 2mw pointer, so I'm going to put in an 20x LOC hoping to push it to 420ma.

Now a couple of questions. Why are lasers more dangerous than burning things with a magnifying glass? And I understand why we control current but why is voltage not as much of a concern? If a diode has a forward voltage of 3v and I supply 3v@100ma that's .3W and one at 5.5v@100ma that's .55W so does power not matter either I mean how can the flexdrive do both, how do it know? Internal resistance of the driver :-?
I'm in Pennsylvana anyone close with a laser power meter?
Thanks, Adam

It's more dangerous because laser light is coherent-all of the photons are moving in the same direction.
I don't know if this is right, but I think voltage doesn't matter as much because the driver regulates the voltage down (or up, in the case of boost drivers), to what the diode needs.

That's a horrible reason why they are more dangerous. Coherence has nothing to due with the eye hazard. If you had a uncollimated beam that was coherent, it would still be a laser. The reason they are more dangerous is because they are collimated and thus have a higher source brightness.