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IR filtering a 50mw

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Jake0021

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So I contacted Susie at O-like asking if she could install an IR filter on the 50mw I was planning on buying and she responded saying that an IR filter is unnecessary on a 50mw. Is this true? Because I've always heard differently.
 





Yea, you don't really need an IR filter on a 50mW laser because the IR is only a fraction of that 50mW output so there isn't much to worry about(assuming you follow standard safety precautions)
 
Photonz said:
Yea, you don't really need an IR filter on a 50mW laser because the IR is only a fraction of that 50mW output so there isn't much to worry about(assuming you follow standard safety precautions)
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What are you talking about? :undecided:

It takes about 500mW of IR to produce 50mW of 532nm.

I would recommend getting a filter no matter what.
 
But is 500mW of IR actually emitted? sorry, in my experience I've heard that the IR emitted on those things is a decent portion of the total output but when the total output is only 50mW then it's probably not that much (estimated 5-25mW of IR).

But, i see the danger if the only thing emitted is a dim red dot because that could be hundreds of milliwatts of IR.
 
It will not be emitting hundreds of milliwatts of IR. I would still get an IR filter if it was me but not having one won't be the end of the world and it may slightly improve burn-ability, as more energy will reach the target.
 
I have a 40mW 532nm ebay pen that has 35mW of IR leakage.

Whether that's an issue is the topic of many debates.

You can't assume because the overall output is small the amount of IR will be small also. It's not proportional.

-Bob
 
I wouldnt want a laser over 20mw green that has no ir filter since your eyes cant see it, so why risk getting eye damage? not worth it.
 
Considering IR can't do any damage if it doesn't hit your eye I honestly don't see the big debate over it.

Especially since no laser should be hitting your eye anyway. As long as you are careful, you are fine.
 
bata said:
Considering IR can't do any damage if it doesn't hit your eye I honestly don't see the big debate over it.

Especially since no laser should be hitting your eye anyway. As long as you are careful, you are fine.
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What?

You do realize for example a 100mW has let's say, a 1W pump IR diode. Which is quite sufficient to ignite materials...

Lasers don't just cause damages to people's eyes.
 
Tha Greenlander said:
What?

You do realize for example a 100mW has let's say, a 1W pump IR diode. Which is quite sufficient to ignite materials...

Lasers don't just cause damages to people's eyes.
Click to expand...

This doesn't sound right - I've checked the wiki on DPSS and according to it most green DPSS lasers have around 1/5 efficiency, ie 20%. Your example implies only 10% efficiency, which as far as I know would be a POS laser...

I'd also like to stress that just because the IR diode is of X power, does not mean that same amount of power is being thrown out the front of the laser. That'd be silly. Otherwise, 100mW greens would be LPM'ing as 4-5 times their power. If the laser leaks that much IR, it's surely buggered and should be treated as faulty and hazardous.

Rather interestingly, some of the less common wavelength lasers have much lower efficiencies, well into single figures, so DPSS is overall very wasteful.
 
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Cheap laser pens are a different ball game. It's not surprising they piss IR everywhere when the beams arent even straight half the time.

I'd be gobsmacked if the laser the OP wants to buy were to put out 500mW of IR (unfiltered). As I've said above that would mean the laser would LPM at least 10x it's stated output power.
 
mortuus said:
that sounds pretty dangerous to me that much IR goes out.. and since you cant see it you wont react to protect your eyes :(
Click to expand...

You still have green light coming out. How would you not be able to react to that? The only time this would be a real hazard is when the crystals get out of alignment.

If you are worried by all that IR leaking then you should consider that the green light is more hazardous. You better stick to a keychain pointer.
 
I meant the IR, even a good quality without IR filter you never know how much goes out do you?
 
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