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ArcticMyst Security by Avery

XJ-A150 News

X FLY

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^^^^ or, something i noticed with fp and scope guy. stack the 140 and a 150 (complete laser of course) on top of each other, and then put a diffraction grating in front. you'll easily see the different wavelength.

michael

In front of your eye or the laser beams?
 





Benm

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Here's an easy way to tell if they're different. Aim a regular diode (at low power) at a point. Aim the new diode at the same point. Hold a diffraction grating to your eye and view the point.

You might find that you see different wavelengths between A140 diodes this way too. Using diffraction gratings can show small differences in wavelength very well, but you need to measure distance and spacing and do the math to find out what they actually mean.

I'm not sure what the tolerances on these diodes are exactly, but i suppose they could be off by a few nanometers within normal tolerances?
 

Blord

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If they do differ from each other, I hope more nm. More blue the better.
 

Benm

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I'm sure that IF they are different they will be longer wavelength since that would be more visible. I guess we'll know soon enough if they managed to shift the wavelength up further.

One thing to consider is that wavelength also depends on temperature, so if these diodes run at a higher current and get warmer, the wavelength will also shift up. This is good in terms of visibility, but perhaps not for diode lifespan.
 

X FLY

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Would be really cool if the A150 diodes would be closer to 450 or 455 :)
 
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The wavelength of laser diodes can vary as much as 5nm from each other and also depending on the temperature and operating current. In order to accurately measure the wavelength of these new diodes, more than one will need to be measured under temperature controlled conditions. Out of the 5 A140 diodes I have tested, they are all within 3nm of each other when driven at the same current and temperature. I will only receive one diode from DTR. To accurately compare the A140 diodes to the A150 diodes, 4 other diodes will need to be tested by another person under the same testing conditions (temperature and current).
 

iFoSh

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Got my diode from DTR today and it works great! (beam/dot look just like A140 to me too) Thanks bud! +1 for you. :beer:
 

Benm

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I suppose it would take batch analysis to see if there is any manufactured difference in wavelength between these diodes. But even if that proves a difference, the question remains if they are manufacturered differently or just cherry picked from the line of A140/130 diodes.

I have no idea how hard a barrier 445 will prove to break, and certainly hope progress will be better that shortening red wavelengths so far!
 

DTR

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Got my diode from DTR today and it works great! (beam/dot look just like A140 to me too) Thanks bud! +1 for you. :beer:

Do you know the current and output that you are getting?

Most of the 150's that I shipped domestically show delivered by the delivery confirmation. Anybody else do any testing yet?:D
 
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I have got mine yesterday but have had a lot of work of late. Working on my build now, with help from your post on coin heatsinking DTR :thanks:
I usually don't like to post until I see light come out the end, but wanted to put out thanks again for offering these.
Hopefully, if all goes well, I will be able to post pictures this evening of my build. This will not include LPM metering yet though.
 

iFoSh

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I won't have a LPM til I get a Radiant Alpha in the next few weeks. Sorry I won't know anything til then...it's running at 1.5A though.
 

ped

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Hope mine comes quick, got a host here with its name alllllllll over it :)
 
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DTR, I received my diode yesterday. However, I won't have time to do any testing until Thursday at the earliest. I didn't have access to the equipment I thought I was going to be able to use, which means that I'll simply have to use a different (and more time consuming) process to measure the wavelength. I will post the efficiency (current vs. voltage vs. optical power) data when I post the wavelength data.
 

DJNY

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Best way to go with diffraction gratings. Distance between gratings and wall should be big enough cause of only a few nm difference (maybe). Yeah these 445nm diodes vary in +/-5nm. I saw a different dot-space between my (ex)Arctic and my PGL-449nm when shining through the grating.
 




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