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FrozenGate by Avery

IR

yep that's it senkat. it just shows the amount or ir coming out of a laser without an ir filter
 





Aseras --

Good point about IR optics. I built an 808 nM into a Aixiz module last weekend. The glass optics don't seem to focus well at all. It will pop a black balloon but at close range only. My camera shows a blob of IR at 247 mW.
I think I need a different lens for IR.

Mike
 
SenKat said:
Aseras - I see your point (no pun intended) about the video - I THINK (please read that as I am not sure) that his entire point was showing the effectiveness of an IR filter....

yes but keep in mind that most pointers don't leak the 808nm output from the diode, the vast majority of the 808 is pumping the nd:yv04 or yag to make 1064 nm output that in turn pumps the ktp to make 532nm. what you usually see leaking is the 1064 output. you can have either leak depending more on the quality or lack of the HR ( highly reflective )/ AR ( anti reflective ) coatings on each side of the crystals.

The IR filters take up the slack, usually due to over saturation of the crtstal set, which is why jacking up the pot or current to the diode doesn't make a big difference once you saturate the crystals. Take the core for an example. Once you saturate it out, it doesn't matter how much more IR you pump into it it's not going to make any more convert to 532nm.
 
Almost all of the smaller greens I recently purchased have some IR content. Two are 5 mW Leadlight clones, pot modded for xx mW, and there are the true DX30's. Best way I've found to "see" the IR without a meter is to place a 780 nm IR pass filter over the laser output and then take a video with an IR sensitive webcam (to make a webcam IR sensitive just requires removing the internal IR filter). If the laser is still emitting IR, the webcam will pick it up.

The aforementioned way appears to be an easy way to visually check the performance of an IR filter. For example, if I place an IR filter across the laser output followed by the IR pass filter, I can then "see" how much IR is still emitted by looking at the webcam video. The IR pass filter I use is an IR-78 Hoya filter, but the film from a 1.44 MB floppy disk can work in a pinch (although it may not be as effective).

The Novalasers IR cut filters significantly reduce IR emitted from the DX30's, but a small amount is still emitted. Just how much I won't know until my power meter arrives. Some webcam IR removed filters will also work, but they are much thinner than the Novas and may break when zapped with higher power greens.

The only green I have which shows NO IR output in the webcam is an original black Leadlight. I was never able to pot mod it for higher output, so it remains <=5 mW. Maybe the low output is the reason all of the IR appears to be blocked.

HTH,
Jon
 





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