Advice on safe laser

[Porn_star]

A little introduction, my name is Tim, and I've always loved lasers and whatnot. A few years ago I got a focusable purple laser and found it was not filtered. I ended up dismantling it, and tossing it in the trash. I'm an avid flashlight collector, mostly customs with a few factory made lights. I have several from Devin's work, a coolfall, and my most recent purchase was an fl-33. I'm not afraid to spend a little dough if a custom comes along or whatnot.

That being said, I'm looking for a simple pen sized laser which is filtered, but rather bright, without a huge risk of blinding someone accidentally. Mw's don't really matter to me as long as it meets this criteria. I really liked the wicked laser nano series, but they no longer ship to the us. Eventually I'll end up with a large laser collection as well. But this needs to be my first purchase.

Thanks for the time. Show me a thing or two!

Ps, color doesn't matter that much, but I'd like to stay away from red.

 

[Immo1282]

Hi Tim - afraid you trashed your purple laser for no reason - filters in lasers only improve safety of DPSS types (I.e. Most cheap green lasers and some other more exotic colours). A purple laser diode only emits one colour of light (at 405nm) so filtering it is not useful. IR filters are used in DPSS lasers because of invisible IR light which would simply not be present in your purple laser.

The best way to stay safe is to always wear decent laser safety glasses when you're using lasers indoors.

 

[Porn_star]

I didn't know this, but at the same time I didn't need something like this in the workplace. The purple laser did hurt my eyes after a few days. The felt very fatigued, so it was best to get rid of it.

 

[Immo1282]

I didn't know this, but at the same time I didn't need something like this in the workplace. The purple laser did hurt my eyes after a few days. The felt very fatigued, so it was best to get rid of it.

Okay - well I'm glad you realised that you could have been causing some damage before it was too late... If you want something quite powerful, it's well worth looking into getting something that either comes with safety glasses or getting some separately that'll block the wavelength you're interested in. "but rather bright, without a huge risk of blinding someone accidentally." does not really go together so well without protection.

In terms of good companies for a first purchase - Sanwu was mine but they're on the upper end of pricing (make some excellent quality lasers).

 

[paul1598419]

Welcome to the LPF, Tim. Your best bang for your buck is a green laser. This is because our eyesight is more sensitive to green than red or blue, much less violet. You have several options of green lasers. The 532nm are solid state lasers and are pumped with infrared diodes. The others are direct diode lasers and they come in wavelengths from 505nm, 510nm and 520nm. These are actually more expensive than many of the 532nm handhelds you can find on eBay because these 532nm lasers have been around for quite a few years now. You could get one that actually outputs 80 mW for $8.00 or less. Depending on the power of the direct diode lasers you will pay between $60.00 and $300.00 for one. Maybe even more if you are not careful where you buy your laser from.

 

[Benm]

The problem with the 405 nm laser was not a lack of filtering at all, but just the wavelength being barely visible to the human eye (it's on the border of UV).

Green lasers of equal power output appear a lot brighter, but could also put out IR if there is no filter there. Usually this is not that dangerous at some distance from the laser as the leaking IR does not collimate with the green light. But there are direct diodes on the market now that put out a single wavelength like 510-520 nm, and need no additional filtering.

These would look relatively bright too as your eyes are much more sensitive to this color range.

405 nm is so hard to see you could willingly stick your hand in a 300 mW beam because it looks like a cat toy and end up with a blister to show for that attempt - imagine what it'd do to your eyes if looking directly into one.

 

[Pelagius]

Hi
What do you want to use it for? Anything higher in power than a genuinely rated 1-5 mW pointer-see below-is not going to be safe for presentations.
I'd do some reading on safety-and "cheap chinese 532 nm lasers"-which are NOT safe for use in presentations.

If you want a bright laser pointer for use in presentations-I would go for a less than 5mW 530 nm. The cheap Ebay chinese lasers at 532 nm typically lack IR filters-and are almost always way more than 5 mW. I made that mistake!
For presentations I use a genuinely less than 5 mW 510 nm pointer from Laserlands. Being direct diode-it generates no IR

 

[hakzaw1]

My suggestion is to stick to LED flashlights.
There is only one TRUE 100% eye safe laser & it is very hard to find.
It is perfectly safe for anyone to use or 'play' with. Fine for kids..

It requires no batteries, no eye ware , it is invisible to the naked eye and is known as the 'black laser' .000mW at .000nm.

I think your 'symptoms' have nothing to do with a 405nm laser. You would have to shine the laser into your EYES AND NOT BLINK. OR Stare are the 405 dot on a white material for a at the least a few minutes.... and you would never do that.. only a idiot would do that..its insane-- 'erbody and their dogs know that lasers are dangerous.

BTW ..1st thread goes in the WELCOME section. and is an introduction (of yourself)--please go there and READ the posts and the stickies.. and make your proper intro-- (and PLZ use the search next time)

welcome from TEXAS!!!
GREAT to have you here..
hak

 

[Nutball]

My high school had a projector remote with a <1mw red. And boy was it dim. Cat toys are usually <2mw. Anyway, I figure if you could find a .5-2mW green, that outta be pretty safe and bright enough. I recently got my first green laser from a member here, who I think still has some pen lasers for sale. It appears to be a cheap chinese pen laser labelled as a <5mw class 3. It actually puts out 60-80mW and leaks 4mW of IR. It's way brighter than my 250mW burning red laser. You can feel the heat if shined on a black sharpie mark on skin.

Point is, stay away from cheap iffy sources if safety is a concern. Maybe someone here has a metered Green that puts out very low power.

Maybe if you contact Sanwu, they could modify one of their multi mode lasers to output extremely low power. They normally have a 5-10mW low setting which is actually very bright compared to a 2mW cat toy laser, which is sufficient already for pointing on presentations. A 520nm or 505nm comes in 50mW power, I'd think they could swap some resistors or programming on the control board to give a 2mW and a 10mW mode.

I just now noticed Sanwu appears to no longer include multi mode control on lasers under 1W! Bummer, but probably still an option if you beg for it in a custom build.

 

[hakzaw1]

IMO its easier to be safe by being careful ........... I would no more shine a laser into some protected eyes than I would if that person was unprotected..

.. ever been to a concert w/laser show? the only glasses there are the cardboard 'trip' plastic glasses (its a diffraction grating) even the lasershow operators would NOT ~95 % of the time have eye protection 'in use' they MUST have them on their person- around the neck/top the head in a pocket BUT if they forgot and the laser police come (FDA)- one Show OP I know fined got fined $2000 because one of his workers left his in the truck.
ON the other hand-- some 'tasks' cannot possibly be done without them then in place-- and when the powers get very high-- like 5, 10 and 20 W full color-- any place near the projectors is a danger zone and they only peek over them when they must..some read-outs on electronic devices are made invisible when wearing laser protection. ( they are very dangerous when used as sunglasses when driving-- you will not see any red or green lights)

Please understand.. I am not advocating recklessness. & YES Better to be extra safe.. those not experienced around high power lasers are much more likely to get injured.. A 'second sense' (?) comes naturally once you have experience.

btw good luck finding any 532 penpointer less than 5 mW (or less than much more (average is 40 to 80 mW ))-
For a while you could find small 532 modules~5-10 mW at 40$ ..IIRC AixiZ used to sell them- just add 3.2 -4vdc and there you go... afaik the one in my hand ATM is NOT filtered.

To test that simply place your eyeware for green between the laser and your LPM. That blocks most of the green and the rest is IR from the pump OR place a IR filter in front of the laser and compare reading w/o the filter-- that way you will also know HOW much IR there is..we got some DPSS blue handhelds tha were WAY over spec.. then one owner placed an IR filter and discovered that JL had forgot the filter--IF it had been 532nm I doubt that would happen as they have only made a few DPSS hand held lasers. ( that were NOT 532)

- the ones that do make >5mW cost $140 --& are exactly 4.99 mW..& it's used to calibrate LPMs.
One exception-- a 532nm that LEDed.. also know as a zombie or living dead .
IT may be anywhere from 2 mW to 6 or 7mW.

I have a few of those.. (want them?)

no way to repair... one common confusion is the little label on the laser (a FDA 'rule')-- if you REALLY look... you will see < before a number--which, you know, means 'less than' I have lasers at powers like 300mW and 500mW and the labels are the same <XmW -- for that class.. so a laser with <1W could be anything less than 1W like 10 mW-- the power printed was not 'measured' from that laser.... its by class.
typical pen pointer RG or V is class II & reads'< 5mW on the 'V' '405nm +/- 10 nm'--(< that is a lot!)
and while they say' this product complies with 21 CFR' \but it does not. 70 mW is what my meter sez.
if you bid, you can get all three RGV these days for ~1$ each.. ($3) free$hip-- NONE will even be close to 5 mW-& if mine WERE 5mW I would be asking for a refund.. its a zombie already..

last word.... it really has not been very long ago where 99% at LPF were anything less that thrilled at over -spec lasers...it certainly was NOT something that was wrong or bitched about . If lasers were bicycles...pen pointers would be the little tricycles-- and full color projectors and 1+ W hand made and/or top of the line( JL, Sanwu /et al made .would be $$$$ racing bikes .)


..Most lasers lose power over time --good companies like Jetlasers and Sanwu and others intentionally sell overspec lasers so... down the road when its older, hopefully, it still will be spec... I use mine so rarely, most are the same mW as when I got them.. one GB order of JL 250mW 532 PL-Cs (iirc 7 or 8 pcs) metered lowest at ~305mW and 'arythna' got the 'keeper' at 440mW ( the lasers were assigned at random) --mine was iirc 340mW and btw its FS $200-(w/ 10 batts!!)(PLz dont ask me if its 'filtered')- has LOTS of features we do not see anymore. ( shutter-key lock-focus-led 'armed' light- click or constant ON.
. very heavy --lots of brass. 18650 batt-
The goal was for it to be FDA compliant..& JL was close.
Back then JL '(re) maned' the PL-Cs from lower quality Sky Lasers.

 

[Porn_star]

Thanks for all the responses! I am not careless with any laser or flashlight. Some of the lights I have put out upwards of 4000 true lumens and whatnot. I work in maintenance, and would use the laser to point out parts on a robot or whatnot. But there could be folks behind that I don't see and I don't need to hit them in the eye with a 1 watt laser by accident. Even with a 1mw or lower I still wouldn't try to get someone with it. I'm looking for a legitimate lower power laser to use at work. The way I see it, if I'm carrying around a 7 watt laser, and I accidentally put someone's vision out, I'll find myself in a courtroom for negligence. If I accidentally get someone with a low power laser, the most that will happen is a writeup or whatnot.

Its good to know that the 532s are the ones that put out ir light if unfiltered. It's been a few years since I last messed around with lasers so I'm wanting to get a few. The top of my list is one for work at the moment. I'm sure within a few weeks I'll have more than I can remember I have.

 

[Nutball]

I don't know much on the matter, but I'd think you could find a way to add a resistor somehow to limit the power to what you want. Even if it starts at 100mW, why couldn't a resistor bring it down to 5mW?

 

[Immo1282]

I don't know much on the matter, but I'd think you could find a way to add a resistor somehow to limit the power to what you want. Even if it starts at 100mW, why couldn't a resistor bring it down to 5mW?

If the driver uses a resistor/pot to change its current setting then yes, but I'd have thought putting a resistor in series with a LD is just asking for trouble

 

[lasersbee]

I would stay below the 5mW power range of any Laser
you may chose. Green Lasers can be seen much easier
by the human eye at the same powers.

You will need to test the actual power of your chosen
Laser with a calibrated Laser Power Meter to be certain
the your Laser is below 5mW.

BTW...you can put reduction filters in front of the Laser
aperture to reduce it's power.


Jerry

 

[paul1598419]

You can't just add a resistor to decrease the power of a direct diode laser because the effective resistance of the diode decreases as the diode heats up. Drivers are current regulators, not voltage regulators, so you would need to add a driver that provides a lower current no matter what the effective resistance of the laser diode is.

 

[WizardG]

I would stay below the 5mW power range of any Laser
you may chose. Green Lasers can be seen much easier
by the human eye at the same powers.

You will need to test the actual power of your chosen
Laser with a calibrated Laser Power Meter to be certain
the your Laser is below 5mW.

BTW...you can put reduction filters in front of the Laser
aperture to reduce it's power.


Jerry

I think Jerry's last point is a good one. Installing an ND2 filter in a laser303 might be the cheapest way to get a 'safe' green pointer.