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ArcticMyst Security by Avery

New Sharp 487-492nm diodes

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Hello again LPF!

Today I'm sharing pics of my new 487-492nm diodes by Sharp.

I have 3 of them put together at the moment, and I plan to make one more once I get my hands on a hot glue gun to keep the clicky button in place on a pen build... (below: 485, 487, 488, 488, 492, 495: 495nm from the first batch, 485 PLT5-488 in the pic below, and my friend's sanwu pocket 488 on top of the 3 I will be sharing here)


So far, there have been two iterations of these sharp 495nm diodes, the first batch being 492-495nm, and the second being 487-492nm from Paul's measurements. It's amazing how these diodes spread so much in color:


On to the builds...
First up was something a little weird for me to make. I decided to make a little homemade labby out of the 487nm diode. I purchased a 532nm labby w/ fan from laserlands expecting an easy stop 'n' swap out for the 12mm module. For the most part it was :)



Most part... I had two little annoying things to work out. First off, there was a lens glued to the front of the module I needed to get out. Acetone and vice grips tend to make this easy.

The other problem is that the set screw was in the back of the module, meaning I couldn't have a good heat spread to the outer module using the extended back... or the driver attached straight outward. Instead, I needed to desolder the driver (sorry Paul!), and re-solder it to the diode diagonally to fit the cavity in the heatsink:


And with that, put some thermal paste on the copper module, put it into the heatsink and screwed the fan back on.. aaaand... we were done :na:


The fan doesn't move a lot of air, but I did leave it on for a half hour without any noticeable increase in temperature. Guess it does its job pretty well :D

After those 30 minutes, still going strong



______


Next up is a ~492nm build (I assume after heat/extra current) in a C6 host



And vs the 487 labby:



___


And finally, what might be my new favorite laser: a teal powder coated host by Rich with the lowest WL 488nm diode of my 25 inside:


Which lies close to the labby from before (it is being driven a little harder):


I'll cut to the chase. What makes this one REALLY stand out (other than the fantastic host!). When you put it through a diffraction grating, this does something no other laser I've ever seen does:






This thing has a good 10nm spread, all of it with a speckle to it. It gets very visibly deeper blue.




Whereas the other diodes don't do anything close to it:



From a little bluer than my 480nm, to a little greener than the C6 above. Crazy. And all of the output is fairly bright. I just hope this isn't a defect that will shorten the lifespan...

Anyway, that's what I have for now! As always, I add to the albums over time and there will be more pics over on imgur.

next on the list is the 565...
 
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CurtisOliver

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Thanks for sharing, nice builds. :)
That's a weird one you shone through a diffraction grating. It's like a 488 diode wishing to be like his father an old argon. :p
Good job. :beer:
 

Gazen

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Awesome builds! I have that exact same C6 490, it’s great.
 
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Seems you've been busy, Zach. We talked about that one with the 10nm spread. I had found on some of these diodes, at the correct current, they would have twp peaks. These were mostly within a 2nm range, but apparently there is one that has a broad linewidth. This is unusual for these diodes.

Love the photos. It is nice to see all those wavelengths stacked up next to each other. I'm sure the color difference was more acute in person.

+ Rep. Took awhile.
 
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Hi Z,
Wow what a line up of WL's awesome ,well done buddy, and step by step explanation of each. Glad to see the Teal host in action looking good .

Rich:)
 
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:kewlpics: I always knew I would like 500nm, but it's actually 490nm that's the perfect blue green mix that seems to change depending on the background.
 
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Thanks guys!

@RedCowboy - Definitely. 492 is blue during the day and green at night... Or blue when compared with green, and green when compared with blue. This is one weird part of the spectrum, but it's so nice
 
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I have to agree with you there, Zach. Right at 492-493nm is on the edge of green and blue. I still love the very light blue color of 488nm, though.
 
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Good to see all the wavelengths good builds i really like the teal powder coated host looks awsome.
 
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I'd rep you if I could. Wondering if you can take a picture of the first order diffracted beam of that "broadband" laser? With a lot of fog it should look astonishing!
 
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Believe me that's on my to-do list! Though it's odd, I'm finding that it doesn't output like that all the time. I'm starting to wonder if it's a side effect of the astral driver too, as when the battery gets low the output pulses then dies off. I just recharged my battery and I don't see the strange output.
 
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It might be varying the current very fast due to driver instability, causing it to lase at different currents and therefore wavelengths. If that happens on a kHz+ frequency you could probably get that line effect. You could verify that by probing the diode leads with an oscilloscope while it runs, but be careful. If that's what's happening it might be bad for diode life.

Edit: another thing you could check is if the diode lases at very different wavelengths at threshold and 300mA.
 
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They're not as far apart at threshold and at the current I have set as this line shows, though it is still a drastic difference, probably 484 up to 489 (a little bluer than my 485 to a little greener than argon 488). Whereas the line is as blue as my 480 to almost as green as the 492.
 
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Ok, I think it has to do with temperature. I left it on for about 2 minutes then it flickered its way into existence.

Also, not so easy to take a picture of without a lot of setup.
 




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