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Lens question

Yoshi1988

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Hey guys... I have a nubm44 in a s4x host from survival lasers with just a regular focus adapter... I'm currently using a g2 but would like to improve my divergence.. First off would I be better off with a g7? And then if you think a g7 would be best where could I buy one that I can just screw into my current host. Any help is greatly appreciated.. Thanks
 

Alaskan

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If you use a lens with a longer focal length, provided the beam is not so wide it becomes partially truncated, or cut off inside the tube as it spreads, that's the only way to reduce the divergence with a barrel mounted spherical or aspherical lens which will fit inside a small Axiz diode mount. Some use three element lenses to reduce divergence due to their longer focal length compared to a G2 or G7 lenses, but at increased loss. I am not sure if a three element lens is something to use with the NUBM44, due to its high divergence, too much of the beam might be cut off inside the lens holder diameter. Maybe someone here has tried this and it is working well for them, I don't know.
 
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steve001

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Why do folks think the only suitable lens to use has to have a "G" in it's name?
 

dden4012

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Why do folks think the only suitable lens to use has to have a "G" in it's name?
I thought more expensive meant better. I learned it isnt as cut and dry as that. Im going to try a 3 element lense for my 465nm. I dont care for the bar shaped beam.
 

paul1598419

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The point Alaskan made about the focal length is appropriate here. The NUBM44 diverges so rapidly along the slow axis that if the lens can't get close enough, the sides of the beam, and by extension, the power will be cut.
 

Lifetime17

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Hi
I tried all G type for the 44, G2 G9 G7 and by far the 3 element worked out fine . The 3 element will give you a significant power loss but at 6+ to 7W's your still getting enough raw power from that monster diode.

Rich:)
 
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Yoshi1988

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I've tried a 3 element and it seemed to steal a lot of power.. How did the G7 work for You? I'm curious.
 

Lifetime17

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Hi the G7 was ok but the3element was better . Did the 3 element loose around 1-1/2 w's if so that's not bad and that's the way it will be with a 3 element on all diodes
 

steve001

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Hi the G7 was ok but the3element was better . Did the 3 element loose around 1-1/2 w's if so that's not bad and that's the way it will be with a 3 element on all diodes
If a larger diameter lens but of the same focal length as the one you want to replace will fit do that. Is it possible to have a new lens housing machined to fit this laser?
 

steve001

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I thought more expensive meant better. I learned it isnt as cut and dry as that. Im going to try a 3 element lense for my 465nm. I dont care for the bar shaped beam.
It depends on whom manufactured any more expensive lens. Is it AR coated? How precise the surfaces are curved. And the material the lens is made of. Plus other variables.
 

Lifetime17

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Hi,
Our lens that we use are 6.3mm diameter and the barrels are M9 x 0.5 , so yes you would've to custom lens barrel it a transition type .

Rich:)
 




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