IR filters

okay, ive done my research and i am completely dumbfounded. im in the border of being a laser noob and an average laser user, so this would be the extra push that i need. what do infrared filters do to lasers? why are they more expensive? and also, do infrared lasers emit only infrared light? (why would they have that? wouldn't it just suck? you cant even see the beam, and isnt it a safety hazard?) yes, alot of questions, i know. but help a brother out

DPSS lasers like green, yellow, or blue use an IR diode pumped through crystals to make the new colors, but not all the infrared light is converted. That's why you need an IR filter. IR filters really aren't the reason why laser are more expensive. They're pretty cheap. It's more because the companies that use them are higher quality. Laser diodes are monochromatic meaning they only produce one wavelength. That wavelength can change with temperature, but it will never be more than one wavelength. Some people find invisible lasers interesting I guess.

wow, it all makes sense now. haha, thanks man! you're the best! but would an IR filter decrease the burning capabilities of the laser? or would it remain the same?
also, is it possible that i may buy an add-on IR filter for a laser if i purchase a laser that doesnt have one? thanks for your patience -nick

Yes, you can buy an IR filter and install it yourself just do not use super glue. It does decrease the power output pretty signifigantly in some cases, but the IR light is not focused very well, so I don't think it would effect the burning capability that much.