Battery orientation in lasers

[paul666]

How can we be sure of the correct orientation in cases of lasers that didn't come with documentation? Is there a general rule that we could follow?

i have several lasers and have bought more recently and waiting for delivery, the site what i last purchased before these dosn't say anywhere which polarity , even after e-mailing them they havn't replied [ laserpointerpro ] Grrrrrrrr
so.......... as its a cheap green dss id say with a spring its a - what goes in 1st
i am also NOW going to put in a book what polarity for them, with pictures lol
and maybe a white sticker [ small ] on to say which way as well...
it isnt good if you paid £100 plus for a laser and it dosn't say what way you put batteries.....it's ok if you have just ONE laser but i have 3 now, and 2 more coming, at least Sanwu [ where these are coming from] tell you what polarity........clap hands.

But it is easy im sure for a manufacturer to just put - or + on a laser for god sake.. come on guys!

 

[paul1598419]

This thread is over 5 years old and many of the participants aren't active any longer. Please don't necro post old threads.

 

[hakzaw1]

No, not all are like that most are, some lasers have reverse protection built in some if you accidentally put in wrong way you don't kill the laser,of course you would immediately turn of trying and switch battery around then try, but most are positive outwards but i have a few the other way around my red lasers in my signature are positive inwards

I use tiny ultra fine tip sharpie to put my +s and -s somewhere--often near the spring inside the tailcap OR inside the batt tube.
OR a white=out pen for writing on black surfaces.
FYI (and anyone who knows better pls reply)
reverse Polarity protection CAN in some lasers mean if you get it wrong-- the diode is protected BUT NOT always the driver.

The driver costs less. But until replaced your laser will still not work.
NEVER gamble.
its 50-50 that you will guess correctly or wrong.

AFAIK all or almost all DPSS lasers are case positive.. but that rule may be wrong.

 

[m3vuv]

i was always under the impresion all visible lased diodes have the can/case+ve?,anyone else heard that?

 

[paul1598419]

No. It is possible you are referring to a 532nm DPSS laser pointer as the 808nm pump diode is almost always case positive. Most other direct diode lasers are never case positive. These 505nm laser diodes are an exception to that rule.