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ArcticMyst Security by Avery

3 element lens on 2.5w 445nm

Joined
Oct 3, 2013
Messages
32
Points
8
Hi!
I just wish to have some technical reviews about putting a 3 element lens on a 2.5w 445 diode. I want to have a more squarish dot and with less spash sometimes when i have long distance pointing needs.
I don't care so much about the loss of power, i will not use the 3 element all the time, for burning needs i will swap with g-2 lens! :yh:

I asked jayrob about the price of the lens, he said me that with the reflections inside the lens holder it will reduce the lifetime of the diode. I trust his technical knowledge, so i just ask some reviews and advices

If the 3 element is really not recommended, is there any other lens that will fit my needs, i searched so much here but didn't find anything about this problem of lifetime reduction.
The only lens i found is the o-like lens which seems approximately the same...

For the record it's a 501b build by Blord, so great build, thanks you again Blord if you read this! :thanks:

Thanks in advance all! :thanks:
 





SKeeZ

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Joined
Sep 2, 2013
Messages
463
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the problem with the three element is that it clips the output and reflects part of it back into the diode, so jayrob is correct on this one. there is no way to get a square beam without VERY expensive and hard to find optics So, my suggestion would be a G-2 or G9 lens.
 
Joined
Oct 3, 2013
Messages
32
Points
8
Thanks for the confirmation!!
With a g-9 lens there will be a difference in the dot? I didn't found a photo here.
 
Joined
Jan 29, 2012
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Theoretically it could be a problem, but I have been using one on my +2.5W Saik with no loss in power output when I retested it after 6 months - I got almost an identical power graph. 3 ele was used for viewing beam and G2 used for LPMing and engraving wood. :beer:
 
Last edited:
Joined
Oct 3, 2013
Messages
32
Points
8
Theoretically it could be a problem, but I have been using one on my +2.5W Saik with no loss in power output when I retested it after 6 months - I got almost an identical power graph. 3 ele was used for viewing beam and G2 used for LPMing and engraving wood. :beer:

Thanks for the advice!
For the dot quality the 3 element is still the better? I think so.
I don't know what to do exactly... ;-)
 
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Blord

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Dec 24, 2007
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The dot looks better with the 3-element glass lens. The dot is larger and for pointing far it is better suitable. You use the G lens for maximum output and burning stuff.
Why don't you buy the lens and try it out ? The lensbarrel is compatible with the G-lens barrel.
 
Joined
Oct 3, 2013
Messages
32
Points
8
The dot looks better with the 3-element glass lens. The dot is larger and for pointing far it is better suitable. You use the G lens for maximum output and burning stuff.
Why don't you buy the lens and try it out ? The lensbarrel is compatible with the G-lens barrel.

I think i would definetely try, i just want to be sure there will be no damage to the diode.
I wanna buy the complete barrel with focus ring, so i just will have to swap it and not disassembly the barrel to swap lenses.
Will you sell me a complete one with focus adapter?
 

Blord

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Dec 24, 2007
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Sure, I sent you a 3-element glass lens with one of the Moh extended focus ring.
PM me for details.
 
Joined
Oct 3, 2013
Messages
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8
Thanks Blord you're more than a great builder! Thanks for your support!
Pm sent!
 

honeyx

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Joined
Jun 12, 2011
Messages
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There is nothing to worry about by using a 3 element glas lens. I´m having here a 445nm laser that is already several years old and am as far I know the 3th owner. I´m having the laser already 2 years and am using it regulary to kill some Aiptasia anemones in my sea tank. Used till now the 3 element lens the laser came with and there was no decrease in power.

Just recently I ordered a new 3 element lens coated for 405nm from odicforce to compare how it performs against my old one. The new one has about 1mm longer focal point but nevertheless performs slightly better than the old one. The output incrased a bit and the dot is more clear. Plus the side splashes are spreaded more far away from the center at a bigger angle so only will be noticed at really small distances.
 




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