$30 Green Laser

[Livinloud]

yeah but you'd need a LPM to figure out how much IR is present. an IR filter will block the IR beam but IR is invisible anyways so it doesn't make a difference if it is unfiltered or filtered, you cant see it.
if you had a LPM you could test it unfiltered and get the output of both 532nm and IR combined, then compare that to the filtered test, whether that was filtering out the 532nm or IR depending on the filter used. when comparing those results you can tell how much IR there is.
get what im saying?

 

[hwang21]

Yes, but if there's a significant amount of IR coming out, just filtering it will make a big difference on burning power/speed, so you can guesstimate it from .

Edit: Assuming you don't have a LPM^

 

[HitShane]

Just block the green and use a camera to look at the ir...

 

[Livinloud]

Or just switch to 445nm and not worry about IR :na:

 

[HitShane]

http://laserpointerforums.com/f52/review-lpm-d-ebay-pens-405-532-650-a-80195.html