how to quickly tell if a laser has reverse polarity protection?

Is there any quick and simple way to test if the driver of a laser has reverse polarity protection?

I've heard one method is to run a very low reverse current through the driver and see if there is any flow, but I don't have any equipment that can generate such currents. I guess I could always put the batteries in backward and see if the board fries, but I'd rather not find out the hard way.

Did anyone ever end up selling / producing my "magic" polarity flippers?

I think I gave the schematic / board to benmw with my blessing to use as he saw fit, but I've lost touch with who even sells drivers etc these days. If there's interest in those circutis, I'd open source them.

Yeah I have a couple of these I got from Cajun. I havent used them yet though.

ixfd64;

Some drivers can be damaged by large reverse current.

With an adjustable power supply, apply reverse voltage thru a 100 ohm resistor and watch the current level.

If it climbs more than 100 ma, I would stop the test before damaging the circuit.

LarryDFW