So you wanna build a green laser...

Thanks for the sticky.....

I want to clarify one thing that I have seen mentioned many times.

Frequency doubler units made by Coherent, Continuum, or Spectra Physics, such as this:
Newport Spectra Physics Frequency Doubler Model 3225-1 - eBay (item 250553771290 end time Jan-01-10 21:04:46 PST)

WILL NOT MAKE 532nm LIGHT IF YOU SHINE A POINTER OR HIGH POWER 1064NM LASER INTO THEM!

These doublers are single pass meaning they have very low efficiency at low powers. They are designed to double the output from high energy q-switched lasers only.

tnx for that beautiful idea!!!:yh:

Excellent writeup +1 :beer:

yap!!! can u pls. teach me how to build

Ok, question. I bought a green laser pointer and have been thinking of seeing what can be done with it! I have a plan, there's a 808nm 1W diode on sale cheap enough and I'm thinking of seeing if it can take it. Firstly, the heat, a problem I'm already aware of but there aint much I can do about it, means it will have to be used in short pulses, as for driver board mods ECT I'm open to suggestions. Thing is, I'm hoping it can still run on 2AAAs

Nirmarea said:

Ok, question. I bought a green laser pointer and have been thinking of seeing what can be done with it! I have a plan, there's a 808nm 1W diode on sale cheap enough and I'm thinking of seeing if it can take it. Firstly, the heat, a problem I'm already aware of but there aint much I can do about it, means it will have to be used in short pulses, as for driver board mods ECT I'm open to suggestions. Thing is, I'm hoping it can still run on 2AAAs

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There's more to it than just slapping a bigger IR diode on on a 5mw pointer. Higher powers need larger crystals as well as definitely benefiting from proper heating and cooling.

qumefox said:

There's more to it than just slapping a bigger IR diode on on a 5mw pointer. Higher powers need larger crystals as well as definitely benefiting from proper heating and cooling.

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Well, thing is this was more of an experiment than a proper project so I have slapped another 5.6mm can in with more power and it seems to have worked, trouble is it seems to perform best at room temprature and taking as long as 1 minute to heat up to full power from cold start. I put it in a flashlight housing and even though it looks kinda a crude effort, it still looks sweet
I estimate it puts out around 100mW or maybe more and with the focus set properly (Pinpoint) it can light a match, nothin really special but not bad considering the whole project cost less than $10!

Gonna post a guick how-to on it as soon as I can blag my girlfriend's camera to take a few shots :thinking:

Nirmarea said:

Well, thing is this was more of an experiment than a proper project so I have slapped another 5.6mm can in with more power and it seems to have worked, trouble is it seems to perform best at room temprature and taking as long as 1 minute to heat up to full power from cold start. I put it in a flashlight housing and even though it looks kinda a crude effort, it still looks sweet
I estimate it puts out around 100mW or maybe more and with the focus set properly (Pinpoint) it can light a match, nothin really special but not bad considering the whole project cost less than $10!

Gonna post a guick how-to on it as soon as I can blag my girlfriend's camera to take a few shots :thinking:

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I think 80mw or so will light a match focused. But still an improvement over 5mw I guess. Be interested to see how it's lifespan is now though. Cheap lasers don't usually use the 'finest quality' materials, after all. I always wondered if you pulled one of the higher powered ones apart (the 100 or 150mw modules) heated the KTP, and cooled the YVO4 to the optimum temperatures and used a larger pump, how much power you could really extract from those crystals.

qumefox said:

I think 80mw or so will light a match focused. But still an improvement over 5mw I guess. Be interested to see how it's lifespan is now though. Cheap lasers don't usually use the 'finest quality' materials, after all. I always wondered if you pulled one of the higher powered ones apart (the 100 or 150mw modules) heated the KTP, and cooled the YVO4 to the optimum temperatures and used a larger pump, how much power you could really extract from those crystals.

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Well I did say I replaced the diode, ya can easily rip one out of a CD burner or pick one up on ebay. I'm running my diode at roughly 90% so the lifetime will be longer than it was usually. I wanted to put a 1W diode in it but I'd have to run it in short cycles so it don't overheat. Like I said it looks kinda crude an it's hardly a jayrob model but it's a good attempt using only stuff lying around in the average household

****CD lasers are 780nm. The lasers DVD technology uses are 650nm. Neither one will work as a DPSS pump diode to get green, which needs 808nm****(Quote)

SO yeah, buy one! and another protip, double check any info written by a stonerlol
Cheers qumefox

Nirmarea said:

Well I did say I replaced the diode, ya can easily pick one up on ebay. I'm running my diode at roughly 90% so the lifetime will be longer than it was usually. I wanted to put a 1W diode in it but I'd have to run it in short cycles so it don't overheat. Like I said it looks kinda crude an it's hardly a jayrob model but it's a good attempt using only stuff lying around in the average household

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Well here it is, how I built mine, but first of all, a quick thanks to Wiki for te DPSS diagram and randomlugia for the pic of the orig laser pointer before I modded it,
**** The one in the pic is actually a 405nm ,5mW blue one, but they look the same!****

This is a similar model in blue to the one I bought



I took it apart and used cutters to sheer away the casing all the way up, leaving only the driver board and DPSS casing, I removed the diode can and replaced it with a slightly more powerfull IR diode (Cheers for the image wiki :thanks



Soldered it all back together, ripped of the momentary switch and shorted the contacts out with a length of wire, which leads to the torch's push locking switch, I had to reverse the polarity of the torch.
It was case negative but as any of you who have these 'New wish' style laser pointers know, they are case positive (Due to the IR diode).
I simply put the spring assembly onto the torch's switch, batteries in the other way, problem solved!
I then took the LED board out of the torch with the diodes and cut the reflector bigger, then using tin foil, (Alu foil for you americans ) made a rudimentary heatsink to fill the gap between the reflector and DPSS assembly



Ran a wire from the casing of the DPSS assembly to make contact with the exterior of the torch and put it all back into the housing



Full kit :



And assembled and on :



Dot beside the UV lights in my room



Dot in jointsmoke (DISCLAIMER I am in no way condoning the building of lasers when high lol)




Dot in MILD jointsmoke and medium light

Nirmarea said:

Well I did say I replaced the diode, ya can easily rip one out of a CD burner or pick one up on ebay. I'm running my diode at roughly 90% so the lifetime will be longer than it was usually. I wanted to put a 1W diode in it but I'd have to run it in short cycles so it don't overheat. Like I said it looks kinda crude an it's hardly a jayrob model but it's a good attempt using only stuff lying around in the average household

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Um. I'm confused about your statement here. CD lasers are 780nm. The lasers DVD technology uses are 650nm. Neither one will work as a DPSS pump diode to get green, which needs 808nm. When you said 'replaced the diode' did you really mean the whole 12mm module instead?

What I was talking about was taking one of these higher power green pointer modules, extracting the YVO4 and KTP crystals, and heating/cooling them properly with TEC's with a larger pump diode to see what these particular crystals were capable of in a proper environment.

And I think this thread is about building a green DPSS from scratch using raw components, rather than just putting green modules in hosts.

qumefox said:

Um. I'm confused about your statement here. CD lasers are 780nm. The lasers DVD technology uses are 650nm. Neither one will work as a DPSS pump diode to get green, which needs 808nm. When you said 'replaced the diode' did you really mean the whole 12mm module instead?

What I was talking about was taking one of these higher power green pointer modules, extracting the YVO4 and KTP crystals, and heating/cooling them properly with TEC's with a larger pump diode to see what these particular crystals were capable of in a proper environment.

And I think this thread is about building a green DPSS from scratch using raw components, rather than just putting green modules in hosts.

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No, I replaced only the 5.6mm diode can but the confusion was my fault, I thought CD players were 808nm lol. I bought mine.

As for building from scratch, the callibration needed for that is a little beyond the tools I got here, untill I get a workshop set up I might as well be building lasers in the stone age, I aint even got a vice lol.
All in all green was mostly an experiment for me, I'm more used to working with axiz housings and red or UV diodes and untill I ripped one open my knowlege was extremely limited but at least it worked out!

Nirmarea said:

As for building from scratch, the callibration needed for that is a little beyond the tools I got here, untill I get a workshop set up I might as well be building lasers in the stone age, I aint even got a vice lol.
All in all green was mostly an experiment for me, I'm more used to working with axiz housings and red or UV diodes and untill I ripped one open my knowlege was extremely limited but at least it worked out!

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You might be surprised with how little it takes, with some patience.

Read this thread, and the continuation thread linked in the last post on it.

http://laserpointerforums.com/f52/o-like-crystal-40671.html

Just read it, I read most of the posts on green lasers here before I decided to go cracking the casing coz like I said, I had little knowlege of the green ones beyond 'Ooooh! Shiny!', the driver is no trouble but anything that requires precision beyond hittin it with a hammer is beyond me untill I get my working space back
=[
I'll still justify my self pride being it was my first green build, incredibly low cost and it well outperforms the pointer I got!
Since the guide was written I've added a tab on the IR filter so it can be removed easily for burning and added a stopper on the focusing lens so when screwed in tight it's as close to infinite focus as I can get.
With the help of my friends and the kind permission of my neighbours a few blocks away I used a pair of binoculours to set the focus on their outside wall (They did look at me kind of funny when I was at their door untill asking permission but after explaining they were fine with it and agreed to keep their curtains closed untill I gave them the OK).

A few manual checks standing beside the projected dot on their wall showed it to be almost the exact size of the dot I'd drawen for referance. Kinda a crude and cumbersome methood but I recon I it down pat. (There's gotta be an easier way without lab equipment)

As for the thread, if I'm building something less crude then it's definately worth a look but it's a definate no untill I get better tools and a good working space, working in this room is like letting a bull loose in a china shop and it's the fast track to getting your nice new parts broken and lost!

Looking at the set up there I noticed, the cooling plate used can easily be harvested out of a mini fridge!!, I took one to turn into a water cooler and it works well so I'm assuming they're the same, either way, it's usable!

Still, something of that magnetude is way beyond me untill I get space cleared, though the cooling plate might be a good idea for some of my axiz housings, kept at low temprature I should be able to push them a little harder without the diodes going kapoot!