/diy/ - Do It Yourself

I often see laser diodes driven with a constant current, but then that constant-current is PWM'd, as opposed to just adjusting the current. I get that lasers don't work at very low current values, but I don't know to what extent that would effect a laser like this in normal operation. My machine shouldn't need to go below 20%, though having a very low power rating as a pilot beam is pretty handy. I have a 30W electrical power laser diode and I'm considering replacing its 12V-only driver board with a custom one that can handle 24V. Maybe I just design it so it could do either and test it out.

Also if someone can recommend me a seller/brand of laser diode (sub-$200) that actually has a tight focus that would be cool. Sick of astigmatism.