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star pointing laser w/o IR leak

lazylazer

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I read that cheap green laser pointer may emit high levels of IR that can damage eyes. I happen to have a cheap green laser pointer and have some questions:

- if I point the laser into the sky, can the high levels of IR still injure my eyes or cause other danger?

- do red or violet laser pointers leak IR or just green?

Given the same power consumption (NOT output power), what color laser pointer would be brightest? Red because the pointer is more efficient, or green because our eyes are more sensitive to the color?

What is the cheapest green laser pointer that does not leak IR and where do I buy one? I found one at laserglow for $39 that specifically say it does not leak IR. Is this a good buy?
 
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Encap

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Green is by far the brightest to human vision. You can check relative brightness here: Relative Laser Beam Brightness Calculator: (647nm 1mw) vs. (442nm 1mw)

You can always buy an IR filter for a couple of dollars and install it yourself alot of them are available on Ebay or you can get one from here: 808nm,1064nm IR filter [OL-FL] - $3.50 : Zen Cart!, The Art of E-commerce

520nm green is a laser diode and has no IR output---532nm green is a DPSS system and has IR leak if not filtered out.

The laserglow pen is OK but has only a small output power.

Have a look here for good quality pen style either 520nm or 532nm LP 520nm 532nm 1-50

Higher output and better/bigger host models here: PL 520nm 532nm 100-1000

Optotronics has high quality IR filtered 532nm pens also, if you like pens: https://www.optotronics.com/green-laser-pointers.php
 
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Sta

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I'd go with the LaserBTB LP models, as Encap suggested. They are much cheaper than laserglow and probably better for your uses. Just be sure to select 'IR filter installed.'

Also:
Pointing the laser in the sky won't ever hurt your eyes, period. The greatest danger is from staring at the dot on a surface (if there is IR present.)

And red and violet pointers do not leak IR.

Encap is correct on all points!
 

Rivem

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I'd go with the LaserBTB LP models, as Encap suggested. They are much cheaper than laserglow and probably better for your uses. Just be sure to select 'IR filter installed.'

Also:
Pointing the laser in the sky won't ever hurt your eyes, period. The greatest danger is from staring at the dot on a surface (if there is IR present.)

And red and violet pointers do not leak IR.

Encap is correct on all points!
I agree on all counts as well.

There's also the risk that the IR is considerably less collimated than the 532nm beam, so shining in proximity (but not hitting with green) to people or IR reflective objects might still be an issue.
 

Pman

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I would be FAR more concerned with the beam hitting someone's eye than anything to do with IR.
Laserbtb is a good choice and you should be going for the 50mW one with IR filter and use coupon code "offroad" for 6% off if it still works and with shipping I believe it will be just over $40 choosing slow shipping. It is decently built and is not focusable but at that output there's really no reason for it anyways. All of my purchases from that company have been overspec.
 

Razako

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Don't worry too much about IR if sky pointing is the goal. Anyway,I'd recommend something from laserbtb as pman has suggested.
 
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Cel

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I agree with above 2 posts.

People are overreacting to IR. Any higher powered DPSS will burn your eyes, regardless of IR leak or not. As long as you aren't pointing at other people or at mirrors or windows, there shouldn't a problem under 50 mW. Heck, even 100 mW.
Outdoor pointing can be safely done even at few watts of power.
For burning or pointing indoors, use laser protection glasses.

Knowledge, precaution and reason will keep you safe. :)

And: with great power comes great responsibility. :beer:
 

Benm

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IR usually isn't that big of a danger with DPSS lasers as long as they are working properly. One of the ways to get a serious injury is to be stupid enough to find your laser not working, and then looking down the barrel if any light comes out. At short range that can certainly cause serious damage to your eyes, even if you only see a 'dim red glow'.

As for star pointing: If you want green you could go for a DPSS, but those work in a limited temperature range. I suppose you do this mostly outdoors, and if you do it somewhere cold (or extremely hot) a direct-green diode model could be preferred.

Most models will produce green light in at least the 10 to 30 centigrade range, but especially below that can be problematic - so be careful if you live up nort and/or point at stars from a mountain top at night.
 




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