I.R. Filters

[patd]

Could someone explain to me the importance of having a IR filter on a projector. Are their other means to take the place of a IR filter?
Does anybody use their projector without a IR filter?
Thanks

[gottaluvlasers]

IR filters are for the green lasers and DPSS blue lasers. Those types of lasers use an infra red laser diode to pump crystals which in turn emit the visible laser light we see. IR filters are used to block the IR light from the original pump diode to emit from the aperture. (obviously, i am HIGHLY simplifying these processes by the way). IR is bad because it is just heat. We cant see this radiation but it is dangerous because it will burn. IR filters are used to block this heat (some will always escape. it is part of the lasing process) but the filters are used to drastically reduce this dangerous radiation from escaping.

I have seen Chinese laser modules with as much as 60-70% of the power strictly IR. In other words, a measured 1 watt green laser, after blocking the IR (either with a filter or off of a mirror/dichro) actually only measure about 300-500mW. I have *HEARD* even worse results. IR filtering is very important.

Diode Laser modules (405nm, 445nm, 635nm, 640nm, 660nm) do not emit this IR. It is with DPSS (Diode Pumped Solid State) Lasers when this dangerous IR is emitted.

-Marc

[patd]

Thanks Mark for taking the time to reply to my question. As you can see I am a complete novice when it comes to lasers.
So do you think these lasers are ok without a IR filter?
Product Name: M-445RGB1W Full Color
Laser modules:
RED 650nm 500mw, Analogue
Green 532nm 200mw, Analogue
Blue 445nm 300mw, The newest laser module of blue Analogue

[LaNeK779]

these red and blue lasers do not need IR filters as they are diodes and not DPSS
the green is dpss, so in theory it should already have an ir filter installed somewhere in it.

we should also bear in mind that all the optics in the optical path are not designed for IR (dichros, galvo mirrors etc) so maybe they already cut the IR off, before it exits the projector apperture