# Red "PGL"?



## AJ_Dual (Aug 26, 2005)

*Red \"PGL\"?*

Deci3ver's thread got me thinking...

I'm a aware it's an oxymoron since the "G" in PGL stands for GREEN. So yes, technically it's a "PRL III or whatever…

I'd hope everyone understands I'm using "PGL" as a universal, like "Kleenex", to mean "handheld black portable laser that takes C batteries, and is significantly more powerful than "pen pointers".

I know all the interest is on green right now, but it's easier/cheaper to up the power on a single stage red diode laser. Even the low end un-modded 5mW pointers use a whopping 500mW IR diode as the first stage. Why not visible 560nm-ish red at a couple hundred miliwatts? I know that's a toy many of us would like to "play" (responsibly and in accordance with all laws and regulations) with. And it should be cheaper and easier to make than a green DPSS.

So does such a wattage and formfactor exist?


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## IsaacHayes (Aug 26, 2005)

*Re: Red \"PGL\"?*

I think Craig (ledmuseum) got a 100mw module once off of ebay or somewhere. You could put that into a 2c case, or even 2xAAA if it was small enough in diameter.. I don't know anyone that sells pre-built higher than 5mw....


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## The_LED_Museum (Aug 26, 2005)

*Re: Red \"PGL\"?*

Go here to see my take on the 100mW red diode laser module. /ubbthreads/images/graemlins/smile.gif


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## comozo (Aug 26, 2005)

*Re: Red \"PGL\"?*

Even the low end un-modded 5mW pointers use a whopping 500mW IR diode as the first stage.

Are you thinking red diode lasers use IR diodes? Red diodes are direct injection diodes

Red diode laser can produce light at a wave length no shorter than 635nm + or - a few. 560nm is still a greenish yellow.


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## AJ_Dual (Aug 29, 2005)

*Re: Red "PGL"?*

No, no, no Comozo...

I know that red diodes are single stage, I was just using the example of the relatively powerful IR pump diodes in GLP's as an example of what high powered IR diodes are commonly availible. Why not visible red?

I was wondering why direct-inject red diodes of similar power to the IR ones aren't more prevalant. "560" was a typo, I meant 650nm.

The 100mW module that LEDMuseum has in his "Trophy case" is a good start, but are there higher out there at relatively decent prices? 

I'm just wondering aloud that if 500mW IR diodes are to be found in every $65 GLP which has more parts/expense in the extra assembly steps, IR filters, Nd and KPT crystals etc., assuming enough quantity were made, why can't we get a 500mW visible red pointer for $65 or cheaper? (Add costs for keylock, delay, and interlock to make them FDA-importable…) 

If 532nm green has approximately 20x apparentl brightnes than 650nm red, then a 500mW red laser should still look about as bright (this is a very rough guesstimate) as a 20-25mW green. Plus it woud pop baloons, cut elecrical tape and all the fun stuff that the guys with the high-end PGLIII's can do, but at a fraction of the cost. At least in theroy.

Is there something about red diodes that pushing them that high gets expensive as compared to IR? Or are they out there, but there's no quantity break because nobody wants them?


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## comozo (Aug 29, 2005)

*Re: Red "PGL"?*

I suspect demand drives the price more so than anything else.
Take a look here. I especially like the green -yellow wave lengths that are available.
http://www.crystalaser.com


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## Ragnarok (Aug 30, 2005)

*Re: Red "PGL"?*

Been lurking for a while, couldn't resist, had to sign up. First post :nana: (not that it matters much!)

I have a suspicion that the green lasers are enjoying more popularity than red because of the bargain you get with the visual efficiency - they "look" that much more powerful. For visual bang you can't beat green. I like red though, and am considering buying one of those 100mW red modules reviewed at LED Museum (thank you!), though more power is ALWAYS a good thing, in my book.

I assume you want more power in the red for visual slam, but if you want power to burn, one might cheat by piggybacking a nice bright (your favorite color here) "tracer" beam on an IR "power" beam, so you can get the visible kick AND do demonstrations too? (what, a blue burning laser?? How'd you do THAT??) "Goggles on"!  

R.


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## Ragnarok (Aug 30, 2005)

*Re: Red "PGL"?*

Roithner lists a 300mW 670nm red laser diode; there may be others out there somewhere...

http://www.roithner-laser.com/HP-laserdiodes.htm
RLT67300T, 670 nm, 300 mW, TO3, w/o photodiode, datasheet
Price, from their list: US$304.28

R.


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## AJ_Dual (Aug 30, 2005)

*Re: Red "PGL"?*

Yah, 300mW, now we're talking... About $300 U.S. Not too bad, and if I'm reading the spec sheet right, all you need to supply is 3VDC at around 550-900mA. Two AA batteries would run it, albeit not for very long. 

You'd have to think somewhere in China would have it even cheaper though.

Figuring out a heatsink shouldn't be too hard. Worst case senario, a little thermal paste, aluminum fins and a small PC fan on a second set of batteries would be possible. 

Although it looks as though you've got to supply the optics. Getting that lined up properly could be difficult. The lenses would be pretty cheap, but machining a small mount and getting it threaded for adjustability for fitting into a flashlight sized houseing might be a pain unless you're an accomplished machinist with a Harbor Freight mini-mill...


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## Kiessling (Aug 30, 2005)

*Re: Red "PGL"?*

I do not think that 2xAA can provide 900mA for more than a few seconds, if at all. Why are you laser freaks so hesitant to go lithium / CR123? You spend incredible sums on your stuff and then use it with sub-standard cells ... 
bernhard


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## Dpicts (Aug 30, 2005)

*Re: Red "PGL"?*

I almost bid on a 500mW Red 680nm today on ebay, but spent the money elsewhere before the auction closed... the item was: 
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=7540672409&ssPageName=STRK:MEWA:IT

it when for ~$150

Daniel


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## AJ_Dual (Aug 30, 2005)

*Re: Red "PGL"?*

SCHWEET!

It looks as though it would be easier to cool the "C mount" style diode, a lot of metal to transfer heat there, but a one-piece module with optics for a few more $$$ would be prefered.

I've got no machining skills to speak of.


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## Ragnarok (Aug 30, 2005)

*Re: Red "PGL"?*

500 mW, yeah, baby! :rock: Woohoo! Hopefully more of those will show up in the future.

I read somewhere that laser diodes are finicky eaters just looking for a chance to pop, that the lasing/operating voltage range is very narrow, and that only small increases (or spikes) in the driving voltage can kill them. Not knowing much about how to drive these things, do they need adjustable (for fine tuning) or fixed voltage drivers like those used with LEDs? I wouldn't mind trying to put one together but I certainly can't afford trial-and-error!

As for battery size I don't really care - yeah, a slim "pointer" size is cool, but a D cell 500mW red laser "Maglite" mod would be nice too (and last more than a few minutes!).

R.


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## Ebola (Sep 2, 2005)

*Re: Red "PGL"?*

I assembled a handheld 100mw red laser using an AixiZ 100mw premium 650nm module and a streamlight scorpion cr123a flashlight. 

I just drilled out the flashlight reflector to be slightly larger then the threaded portion of the laser module lens. I then screwed the module on from inside the reflector with the lens portion outside. I used a steel spring to replace one of the cr123a cells, and to allow for the fact that the module was longer then the led unit I had to remove from the flashlight. I then wired the module up and away I went. 

The thing is brighter then a 130mw 650nm wall powered unit I bought and pops balloons at more than 20 feet. It seems to run forever on one cr123a battery and appears to be very stable.

I am not handy at all, (I had to borrow the tools from my wife) but this proved quite easy.

The whole thing cost well less than $300.00 to assemble and is very impressive. I have to keep reminding people how dangerous it can be and have learned not to leave it laying around.

I just bought a 100mw 532nm wall powered unit and I am trying to screw up the courage to make it into a handheld as well.


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## EGP (Sep 2, 2005)

*Re: Red "PGL"?*

Ebola, that's exactly what I had in mind to do - fit an AixiZ premium (brass) 100mW 650nM module in a modified LED flashlight. Got a number of flashlights off Ebay, but none of them seem too easy to disassemble the front part of. 

Would it be possible for you to post a few pictures of your modification ?

Would very much like to see what you have done, as I'm more or less in the same boat - no special tools or metal-working skills either, so anything to steal ideas from... err get inspiration from is most welcome... :thinking: 

Cheers,
Erling


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## Ragnarok (Sep 2, 2005)

*Re: Red "PGL"?*

Ebola,

Excellent!  

You beat me to it, I ordered one of the Aixis 100mW premium modules a couple days ago.  I would also be interested in seeing a pic or two of your project if you will. I was also thinking about doing a flashlight-type mod on mine but haven't decided on which one.

I have never ordered from Aixis before, how was your experience with them?

I notice they also say they have high power 635nm modules available but none are listed. Anyone know about these?


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## Ebola (Sep 2, 2005)

*Re: Red "PGL"?*

I've bought a bunch of stuff from AixiZ two 650nm 100mw modules one premium "brass" one and one regular one, some goggles, a power supply and one 100mw 532nm unit. The 532nm unit looked a little beaten up cosmetically when I got it, but who cares it is way crazy bright. They have been quite good and their prices are hard to beat. They replaced a dead module for me no questions asked.

Here are some pix that should give you a pretty good idea how I put this gizmo together. I haven't figured out how to take pictures of the beam yet but its surprisingly visible for a red laser.

I have not done much forum stuff for a while so if the pix get garbled sorry:

OK can someone explain to me how I can attach pictures in this forum? I evidently did not do this right.


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## Ebola (Sep 2, 2005)

*Re: Red "PGL"?*

Trying the picture thing yet again.























Lets see if this works.

If at first you don't succeed, keep trying until all opposition gives up in frustration.


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## The_LED_Museum (Sep 2, 2005)

*Re: Red "PGL"?*

You need to host your pictures on a webserver or other online picture hosting service; they will *NOT* display directly from your computer's hard drive as you have shown now.


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## Ebola (Sep 3, 2005)

*Re: Red "PGL"?*

Well that will teach me to read the FAQ and follow the directions.


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## Kiessling (Sep 3, 2005)

*Re: Red "PGL"?*

try www.photobucket.com if you do not already have a pic hosting service. A lot of us use it around here.
bernie


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## Ebola (Sep 4, 2005)

*Re: Red "PGL"?*

Thanks, I'll try that.


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## Pixel (Sep 4, 2005)

*Re: Red "PGL"?*

Congrat's Ebola,

can you tell us what are differences between cheaper 100mW model and the premium "brass" model? Is there difference in brightness? Brass model draws more current - 150mA vs 120mA, and also can handle up to 4 VDC. So I guess usage of 4VDC will produce ouput power way beyond 100mW?


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## The_LED_Museum (Sep 4, 2005)

*Re: Red "PGL"?*

Congratulations Ebola for getting your photographs to display, but they're too wide (in pixels) for CPF. Please resize them to a maximum width of 800 pixels and then re-upload them (over the existing ones) to correct this little issue.


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## Ebola (Sep 5, 2005)

*Re: Red "PGL"?*

If anyone needs pictures from a different angle or of another area just let me know.

Thanks for everyone being so helpful _and_ patient.

Now if I can only figure out how to take photos of laser beams, I can show something really useful.


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## The_LED_Museum (Sep 5, 2005)

*Re: Red "PGL"?*

Thank you Ebola, for resizing those photographs!!!   :thumbsup:


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## Ragnarok (Sep 5, 2005)

*Re: Red "PGL"?*



Pixel said:


> Brass model draws more current - 150mA vs 120mA, and also can handle up to 4 VDC. So I guess usage of 4VDC will produce ouput power way beyond 100mW?



I thought the only difference between the two 100nW AixiZ modules was in the optics - plastic, or glass in the "premium" brass one. They might be different inside too?

Sounds like three 1.2v NiMH batteries would be just about perfect for the brass model. I wouldn't want to push it, I want the thing to last, but it would be nice to know where the limits are.

Thank You, Ebola for the pics. Your mod looks great :goodjob: !! Cant wait to do mine.


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## Ragnarok (Sep 5, 2005)

*Re: Red "PGL"?*



Ebola said:


> Now if I can only figure out how to take photos of laser beams, I can show something really useful.



You may need a little smoke in the atmosphere and dim ambient light (close the curtains, etc.) to get the red beam to show well. It doesn't take much. Incense or a cigarette works. Also,red beams show up better if you are looking "alongside" the beam (but still at a respectable distance - watch your eyes!!!) toward the laser.


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## Ebola (Sep 5, 2005)

*Re: Red "PGL"?*

I would check the volts on the nimh batteries you are going to use just to be sure. I just did in connection with my green laser project. 

My green laser module needs 2.2 volts and much to my surprise my nimh c cells according to my meter are putting out 1.35v each. For two that puts me well outside my comfort zone at 2.7v. 3 batteries at 4.05v would have you pretty close to where you want to be though.


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## Pixel (Sep 5, 2005)

*Re: Red "PGL"?*

I think the diode is the same. They just widen current/voltage range because the better heatsink. Your idea of using three NiMH AAA batteries is interesting, but take in mind that some fresh charged NiMH AAA's are often above 1.4 volts.


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## Ragnarok (Sep 5, 2005)

*Re: Red "PGL"?*

Thanks, guys! I went and checked the NiMH battery shootout and found out that 1.2v is really the "median" and that freshly charged ones will indeed be somewhat higher. Perhaps I will stick with two cells. Guess I should do some more homework here before I open my mouth! D-oh!  

I just sent an e-mail to AixiZ asking for more info on the voltage range/limits of the 100mW red module. I wish there were better details on their site. Ebola, did they send you a data sheet or any more info with yours?


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## Ragnarok (Sep 5, 2005)

*Re: Red "PGL"?*

Wow, that was fast. The reply was 3 to 3.6 volts. Two cells it will be, then.


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## Ebola (Sep 6, 2005)

*Re: Red "PGL"?*

No, they provided me no info on the red modules, but I never asked. I got the idea to use nimh batteries for my green laser project at their suggestion in response to a question about its voltage requirements. 

All I can say about the red lasers is that the amount of laser output does not seem related directly to the voltage supplied. I have a variable power supply and have not observed any appreciable increase in power by increasing the voltage. 

Having said that, I have noticed that my 130mw red laser does seem to pop balloons faster at 12v than at 9v. The regular AixiZ module doesn't seem to be effected by voltage much but I have not been willing to risk killing it and as such have only tested voltages between 2.9 and 3.2v. 

Truth be told I can't say that I have done any truly controlled experiments using identical balloons inflated to identical pressures to absolutely confirm this anyway. 

I haven't tested my premium module at variable voltages to verify its response either. I suspect that the difference between 2.9 volts and 4 won't be huge but I could be wrong. It lazes consistently using one cr123a and I haven’t been able to observe any difference between used batteries or fresh ones. Two regular batteries, one cr123a or even one cr123a rechargeable at 3.6v should be about perfect.

Once I get a meter I will be able to test this stuff out and I'm sure the results will be interesting either way.


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