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Laserbtb 532nm 300mW (FDA)

Razako

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It's been my experience that green lasers are not IR filtered, unless otherwise specified, as a standard.

I think the rationale there is, the green light represents by far the greatest danger, and even the most efficient IR filter does still reduce output somewhat. Not to mention it's an extra component and cost.

Jetlasers TiB for example, are not IR filtered, unless you asked Jetlasers to add one in. Don't know about the other models.

None of my Skylasers were IR filtered either.
Seems pretty dangerous. An unaware customer could be using the laser to burn something while wearing their 532nm goggles. Little would they know they had a bunch of IR reflecting back into their eyes.
 

InfinitusEquitas

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This makes me reconsider my whole purchase... dont know if i want to buy this IR filter or not. How much output reduction are we talking here?
3% maybe. Not a visible difference.

If you don't want to deal with IR, get a diode laser, 405nm, 445nm, 520nm, 635nm, 650nm. 520nm is green, just somewhat lighter color vs 532nm.

HL 520nm 30mW-500mW

I'd expect maybe a 5% loss in green output. If it's much more than that then it's because the filter is low quality but even a cheap filter should be able to reach that number just fine. Loss in total output would be higher if the IR output is at all significant.
Their eyes would have to be literally within 2-3 inches of the a reflective surface, and even then it's questionable whether they would exceed MPE since the IR is not focused.

Also if it's something being burned, most of the light is being absorbed as heat.

I'm not saying there is zero danger, just don't think that IR is as big of an issue as it's often made out to be. Not if proper caution is taken in dealing with the green light to begin with.
 

BotoX

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Seems pretty dangerous. An unaware customer could be using the laser to burn something while wearing their 532nm goggles. Little would they know they had a bunch of IR reflecting back into their eyes.
All right, I will buy an IR filter. The loss is not significant.
 

diachi

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Seems pretty dangerous. An unaware customer could be using the laser to burn something while wearing their 532nm goggles. Little would they know they had a bunch of IR reflecting back into their eyes.

We'd really need to do some testing of various DPSS greens to prove it. The leakage shouldn't be so high that a diffuse reflection from the IR portion would cause any damage. Keep in mind any IR leaking isn't going to be collimated/focused the same as the visible light because A) the IR will refract less B) The cavity/laser as a whole isn't designed to focus/collimate the IR portion.

Keep in mind you don't want IR leaking in DPSS anyway as it reduces the efficiency - any IR that leaks isn't getting turned into green. Most of the 808nm light should be absorbed by the Nd:YVO4 crystal - with the right dopant % and a diode operating close to center @ 808nm, >90% of the 808nm light should be absorbed within the first <1mm of crystal.

Sam's FAQ on DPM crystals from Casix:

Vanadate doping and thickness: The doping is probably 3 percent and the thickness is 0.5 mm. This results in better than 99 percent of the pump beam being absorbed, most within the first 0.1 mm.
Next up is the 1064nm - which shouldn't leak all that much either - again, any 1064nm that leaks isn't getting converted to 532nm. Looking at some DPM crystals ( the type typically used in our higher end pointers ) the specs suggest the OC is HR@1064nm with R=99.8%. Assuming doubling is being done extra-cavity and not intra-cavity that ends up being a very small amount of IR leaking - even at very high pump/green output power.

Really - it's something that should be tested across various models to figure out the true danger.
 

InfinitusEquitas

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Really - it's something that should be tested across various models to figure out the true danger.
The problem is it varies drastically from laser to laser. I've had same exact type of cheap pen laser output less than 1% IR, and 60% IR, which is pretty crazy imo.

It would help to have a lot more data across the board. Where I'm coming from with regards to IR is based on personally testing idk, 50 or so green lasers at one point or another? And the same understanding of lasers as you from Sam's FAQs (though it seems you've read them more recently :p). So really not not a sufficient sample size.

To me, IR is a concern more so in that I don't want to get a laser that's "tested" by SKY/Jet or others, without IR blocked, and produces significantly higher output on an LPM, but in reality you're getting a 3rd less power.
 

diachi

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The problem is it varies drastically from laser to laser. I've had same exact type of cheap pen laser output less than 1% IR, and 60% IR, which is pretty crazy imo.

It would help to have a lot more data across the board. Where I'm coming from with regards to IR is based on personally testing idk, 50 or so green lasers at one point or another? And the same understanding of lasers as you from Sam's FAQs (though it seems you've read them more recently :p). So really not not a sufficient sample size.

To me, IR is a concern more so in that I don't want to get a laser that's "tested" by SKY/Jet or others, without IR blocked, and produces significantly higher output on an LPM, but in reality you're getting a 3rd less power.

This is true, even between models it's going to vary drastically - at least for the cheaper lasers - due to Chinese "Quality Control". A larger sample size certainly would help though!

Spent a lot of time recently reading through the DPSS section ... I'd love to build a multi-watt DPSS green at some point, just no money for it, so may as well read all I can!

Yes, advertised output with vs without IR is one concern. My concern would be people thinking they have glasses that protect them but in actual fact only protect them from the green portion of their laser. Higher divergence with the IR output will certainly help reduce the risk of damage, but without knowing the upper limit to % IR leakage it's hard to say for sure if people are safe from a direct hit with glasses for 532nm or not.

Agreed though, wouldn't worry about diffuse IR reflections when burning - unless you're being a fool and have your eye a couple of inches from the dot. :whistle:
 

mortuus

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They do offer IR filter install, if u go down on the list u will find it.

IR filter installed 0 Kg
$ 1.61

our power type are tested with IR filtered.

how can u miss this ? and all their power outputs is with IR on and since all their lasers are crazy overspec anyways u should get the IR filter for less then 2$ no big deal.
 
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BotoX

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Hey everyone :D


Just got a Laserbtb PL 532 300mW today and I dont know which battery I should buy. I tried out my laser with this battery:

Nitecore 18650 3.7V 2A 9.6Wh 2600mAh Protected Li-ion Rechargeable Battery-Black+Yellow(NL186)

http://www.amazon.com/Nitecore-Protected-Rechargeable-Battery-Black-NL186/dp/B00D2OCQTE


I usually use this battery for my headlamp. The laser was really weak, couldnt even light a match. So that probably means it's the wrong batteries right? Which ones are the best to maximize the power of my laser?



Also are those red glasses enough to protect my eyes or should I get those eagle pair glasses?



Thanks in advance and best regards! ;) any help would be greatly appreciated.
 

Razako

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Hey everyone :D


Just got a Laserbtb PL 532 300mW today and I dont know which battery I should buy. I tried out my laser with this battery:

Nitecore 18650 3.7V 2A 9.6Wh 2600mAh Protected Li-ion Rechargeable Battery-Black+Yellow(NL186)

http://www.amazon.com/Nitecore-Protected-Rechargeable-Battery-Black-NL186/dp/B00D2OCQTE


I usually use this battery for my headlamp. The laser was really weak, couldnt even light a match. So that probably means it's the wrong batteries right? Which ones are the best to maximize the power of my laser?



Also are those red glasses enough to protect my eyes or should I get those eagle pair glasses?



Thanks in advance and best regards! ;) any help would be greatly appreciated.
Try a nonprotected 18650 if you can find one.
 

BotoX

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