New collimator lens for Blue MM diodes

[Alaskan]

Anyone ever have custom work done making a lens in China? Probably a specialty lens manufacturer would be needed for something like this, making the possibilities fewer and the price far higher.

 

[logsquared]

It is the collimator ^^^^

Right. But look at the divergence the spec sheet gives for a 30um emitter. Its like 1.6 X 7mRad. That's gonna need some more help.

 

[ArcticDude]

I think there is MM diodes for that spec's. It didn't say it's for NUBM44

 

[Alaskan]

I should have added; I'd like to have much larger one made.

That spec shows these are too small, it needs a longer focal length and thus larger diameter to tame the divergence more. What do you guys think is a good output beam diameter after correction? A lot of folk don't like fat beams like I do, I'm thinking most members might want about 10 mm diameter correction lens to produce a 8+ mm beam to help reduce the divergence, but for myself, I'd rather have it be 15 mm diameter to produce at least a 12 mm expanded slow axis.

E:

I think there is MM diodes for that spec's. It didn't say it's for NUBM44

Even with my desire for a corrected 12 mm beam diameter, it won't tame the NUBM44 enough, sadly, need closer to 40 mm to begin taming that beast, but about 54 mm diameter would bring it's divergence down to close to 1 mRad in the fast axis.

I'm making some very rough napkin calculations with that figure, I need to know the divergence and beam diameter of the NUBM44 collimated to infinity using a 6 mm G2 lens to come up with a more accurate estimate. RCB gave me a divergence for his NUBM44 once, basing this on what he said and a 4 mm diameter beam. I could be off some, maybe the diameter out of a G2 is 5 mm, or more? Perhaps the rapidly diverging beam from that diode is giving me an impression it is thicker than it really is right out of the pointer, been a couple of years since I had mine on.

Anyway, this lens has no hope of fixing what is wrong with the NUBM44, far, far too small.

 

[paul1598419]

I don't see a mass produced module working with this lens. You would have to press the diode exactly, or it wouldn't work. Maybe a lens housing that could be attached to a cut down module so one would have the ability to move in three directions plus rotation.

 

[CDBEAM777]

Interesting !!! I tell you....working with a 2.5mm piece of B7 glass...will be a pain in the ass....and radial orientation is critical.

I suppose....working to achieve a really compact form factor...will just always be demanding. The smaller we go....the more demanding...just no free lunch !!

SO....To be satisfied...Pitch, Yaw, X, Y, and radial positioning !!!
With an optic the size of a pea !!! Oh brother...compact yes !!! 100 tpi adjustment screw's....oh yea.....

Challenging !!

Precise optical positioning is a demanding Task Master.....at any size !!

Beam Out

 

[paul1598419]

Great minds think alike. Thanks, CDBEAM. :crackup:

 

[Shotgundrums]

What about one of these is a large aixiz type module and large barrel?? I’d totally make one if I had a lathe...
https://www.edmundoptics.com/optics...ter-x-30mm-fl-uncoated-plastic-aspheric-lens/

 

[Alaskan]

You and me both brother, I believe there is room for something like that with the MM diodes, although a NUBM44 6+ watt 450 nm laser diode is still high divergence even with a 25 mm diameter collimation lens, but for the NDG7475 1 watt 520 nm green laser, that big lens would make a very low divergence pointer with that diode.

 

[trinh hong phuoc]

If they can make nubm44 burn at 100 feet - I can make in a bigger aixiz and cheap -need specific tests or specimens

 

[Alaskan]

I've been wanting to do that, but I didn't find the right lenses at a good price for many of our laser diodes, focal length is where I'm getting stuck, I can find a few lenses cheap, but not at the right focal length at the diameter I want for the diodes we use cheap.

 

[trinh hong phuoc]

To create a square beam for nubm44-I think I need a lens with a focus> 15mm-And indeed there is nowhere sell them or will be as expensive as your opinion-I want to use a lens from old camera- according to your previous ideas

 

[paul1598419]

What about one of these is a large aixiz type module and large barrel?? I’d totally make one if I had a lathe...
https://www.edmundoptics.com/optics...ter-x-30mm-fl-uncoated-plastic-aspheric-lens/

The FL of these is over an inch. You would need something with a bit shorter FL.

 

[steve001]

What about one of these is a large aixiz type module and large barrel?? I’d totally make one if I had a lathe...
https://www.edmundoptics.com/optics...ter-x-30mm-fl-uncoated-plastic-aspheric-lens/

A plastic lens might melt when used with high powered lasers.

 

[Alaskan]

That lens may work out for some MM laser diodes such as the NDG7475 and the NDB7478 multimodes, use the calculator at this link to input the fast and slow angles of divergence for either diode at the lens focal length and diameter: Angular Size Calculator

 

[RedCowboy]

The divergence is so aggressive that this lens would need to sit almost as close as the lens is wide and would need to be of a FL that it could work that close, or we use a primary then this lens.

Just as the raw output clips within the 12mm module you can see it printing on the table under the heat sink in this pic and this is a de canned nubm06, the 44 is half again more divergent.