IR diodes in 532 lasers

AD5WY

Formerly N1EZW, KA1NLE, DA2YO

--... ...-- --..-- ...

(Lately, mostly QRP/CW - WHEN I think it's safe to put my antenna out - lotta "gangstas" in the neighborhood now)

(I got burned on an e-bay thing a few years ago, I haven't touched it since. Maybe it has improved.)

(PayPal - I had an account a few years ago. Some scandal occured, hacking, people got burned; I didn't but I canceled my account. Again, hopefully there are new precautions in place.)

Little update... someone might find this useful. I got a reply from O-Like.

Hello,

I have a question about an item that I ordered recently; it is currently in
shipment.

Item: •Model: OLGA-200, 200mw Gatlin Green Laser

Question: Does this laser have an IR filter?

Thank you

Click to expand...

Hello Jeff

It is no IR filter

Susie

Click to expand...

(ummmm... hehehe... minor language barrier thing... I hope Susie didn't think I was asking if the $189.00 200mw Gatlin IS an IR Filter, versus HAS an IR Filter... gotta have a sense of humor about these things...)

So I ordered 2x "Small IR Filter" from Radiant Electronics. 1 to use on the Gatlin, and 1 spare.

(In case it comes up, I did a search on Radiant Electronics... saw some complaints... I know he is busy; moving, college, etc... So I expect the shipment to be slow. No problems here.)

Not sure what size or how much the radiant IR filters are, but I get mine from laserz4sale

http://laserpointerforums.com/f39/fs-ir-filter-green-dpss-laser-49070.html

They're 14mmx14mm which is actually fairly large for $4.. So I usually cut them up into quarters.. So you basically get 7x7 filters for $1 each that way.

Oh, well... I already ordered this from Radiant. I'll keep that other link in mind (archived it in my " Big 'Ol Text File of Snippets from the Laser Forum, and Links").

The Radiant IR Filters are 5mm x 5mm x 0.5mm, so they will be tiny and (~)hard to work with.

I decided to just mount the filter on the OUTSIDE. That's the easiest thing to do.

I will make a "retainer" out of cut white index card... folding, 2 identical "pages" with holes that fold like a book, with the IR filter on the inside; or maybe 2 pieces of cut white index card, if that turns out easier.

I looked at some commercial pics of the Gatlin, and looked at specs (there are NOT many posted details!). I don't know the size of the aperture hole, bit it LOOKS like it might be bigger than 5mm x 5mm. I don't know about the initial beam diameter, either - it isn't posted (though I am sure it will "fit" w/ 5mm x 5mm.

Whatever, I can work it out.

It shouldn't be hard to mount it on the inside. I imagine the front focusing part will just unscrew and come off. the 'waterproofing' will be due to o-rings.. just like on flashlights that have to come apart.

Yea... I think I might have wasted some money though, with those 5mm x 5mm filters (I will keep them anyway)... I did more searching, and found a company in California, Sunex; their filters are pricy but for me I think it will be worth it.

http://www.optics-online.com/irc.asp?desc=absorptive

... they have larger filters, and also apparantly some hard data on the filter parameters (click the GIF to the right of "Spectral transmittance ... "; the IRC-21s are the ones to use). It is 10:24 local time in Texas, they open in a few at 10:30...

I will be calling them.

If you want larger filters, just order some from the guy in the link I posted. He posts the transmissive specs too you know.. and the ones in your link are no better than the 97% transmission of 532nm that he lists.. And he's in CA too.. so it's not like you'd be ordering them from china.

I have a small pile of IR filters from this guy. They're good quality and they work.

(1) I don't have PayPal - yet. I do need to do that, I just keep putting it off.

(2) He first posted his offer on 3-14-2010. "In Stock: 16". Thread was dead from 6-25-2010 until 3-06-2011, "Lowered price to 3.50 per filter". Someone ordered 3 of them. Last post, 3-09-2011, from daguin, "Got the package". He is *probably* sold out, but again, I don't have a PayPal account yet.

When he's sold out.. he'll update. He always has. He's been selling them for a long time and the most current information is always in the OP.

And you are aware you can use a CC through paypal without actually having an account right? Just ask him to send you a paypal invoice for the total.

qumefox said:

When he's sold out.. he'll update. He always has. He's been selling them for a long time and the most current information is always in the OP.

And you are aware you can use a CC through paypal without actually having an account right? Just ask him to send you a paypal invoice for the total.

Click to expand...

I didn't know that about PayPal, I thought I had to have an account first.
:can:

Oh, well. I need to catch up. I have been meaning to get an account.

(I was multitasking. AND paying attention to my militant cat). I just ordered 2x 12mm filters from Sunex (via phone conversation). $35 + shipping (probably $12). Apparantly shipping out via FedEx today or tomorrow.

(EDIT) Okay, relatively a lot of money, but both of the filters will be re-usable... and I won't need that many.
I figure my next step will be a DIY Red, relatively low power (maybe 50-100mw), then a 405 /and /or 445 (or both), then when The Force moves me, I might get around to building a 1-2 watt Blue to crush the Rebel Scum, for the Glory of the Empire, and to occasionally take on flying saucers.
:tinfoil:

JBTexas,

I wouldn´t care about the small amount of IR comming out of your Gallatin. Even if it puts out 40mW IR. Not the IR will harm you but the 190mW of green. I took a look at the spot of my greenie with my IR filtered Nightvision. There is a dimm well focused IR spot to see. About 10mW strong. This greenie is a 200mW rated cheap DX module with no IR filter puting out 100mW of green. Yours is much better quality with probably less IR leakage than mine.

So not really worth the efford. But if you still want to put an IR filter in front of it to protect your lens against dust, just buy next time a cheap webcam for around 10$. Dissassemble the optics and use the IR filter build in. They are the same like the overprised IR filters you can buy for lasers. And the benefit of such a filter is, its actually round matching your needs.

honeyx;

I *tend* to agree, after using it for a couple of days.

The 200mw Gatlin can burn things really well, even when focused at ~ infinity... in other words I do not have to focus it to a point and to be very close to burn things.

I have a little tripod for it (also purchased from O-Like); it makes experimenting easier.

(1)
So, I gathered some things that seem to burn really well... for some strange reason some black nylon (?) material (outer coating) from a VERY OLD sleeping bag smokes and burns immediately. (the sleeping bag is old and "motheaten" anyway... I cut little pieces out of it).


I burned this at various distances. The material DID NOT burn unless it was IN the green beam. It DOES NOT react if it is just VERY CLOSE / almost "grazing" the green beam.

(2)
I have a radiometer that is very sensitive to light, and it is very sensitive to heat (~ IR). I can get it to spin with a hairdryer set on LOW from quite a distance away.

The Gatlin makes the radiometer go crazy and spin like a Texas Tornado... IF ... the green beam is hitting the black side / vanes. If I move the green beam JUST OFF of the vanes, the radiometer stops spinning.

SO;

Whatever IR is coming out of the Gatlin is probably fairly close in collimation with the green light; which is good.

"Bad" would be a severe IR "cone" coming out... diverging, but bad enough (within a certain distance) to cause retinal injury.

Now I am ASSUMING this is all good. BUT I am inexperienced. For all I know, MAYBE the IR diverges "just enough" to make a "cone" at say, 50, 100, 500 feet... whatever.

In any case, there doesn't appear to be a "wild" "cone" of IR coming out. And of course I will not be aiming it at people.

So, I have about decided not to bother w/ the IR filter on this one.

I will save those 4x IR filters I am recieving for... whatever. Probably DIY projects whenever I can get to that.

I think you have a really good laser. Even within specs. The module itself probably is outputing 200mW green. Your Gatlin is waterproof, so it has already a protection glas against dust and water, but due to some reflections on the glas it looses about 10mW. So nothing to worry about. I measured the greenie that outputs 100mW with an IR filter and it lost about 20mW. So obviosly the about 10mW IR were filtered and about 10mW of green were lost due to reflections.

Also. My nightvision shows everything in a 1:1 ratio. So everything i´m watching at has exactly the same size like watching through my nacked eyes. The IR dot was almost exactly as big as the green dot. Maybe there is a small difference but not noticable this way.

There is for sure not a wild cone of IR coming out of a greenie as there are many other people with nightvisions who will tell you the same. It´s possible like said the IR dot becomes a bit brighter than the green dot, but i couldn´t see any difference. Would have to point at something on a long distance and go close to the dot to compare. But this is to much efford as both, green and IR, will of course become brighter due to the divergence and so also weak enough to not to harm anybody at this distance. The green will be for sure still strong enough to "blind" someone for a short time. But the IR will become total meaningless.

Most decent IR filters made for greens have between 95% and 97% transmittance of 532nm. The last test I did using a 103mW 532 off the filters I buy.. The reflection wouldn't even register on my laserbee.. which won't start reading until 5mW, So that proved it was passing at least 95% of the light since I would have gotten a reading off the reflection if it had been any lower efficiency.

If your losing 10% off off one then that's a fairly crappy IR filter.

Or it´s just a crappy greenie from dealextreme beeing labeled as 200mW and just having 100mW total putting more IR than yours. So maybe it´s not 10mW IR but lets say 17mW and the rest reflection. This module is driven with 520mA and for sure putting more IR than an o-like 100mW rated one with better alligment and therefore needing less power to get 100mW out of it. As far I remember 100mW O-like modules are using a 300mW IR diode if I´m correct, but this one is obviously using a 500mW diode.

so if u dissected a 200mw green laser, and somehow "took out" the crystal, then you have a 1W+ IR laser?