The Divergence Changes With the Angle the Laser is Held

One of my 445nm is doing something....unusual.

Its a 140 diode running at 1000mA from a Microboost, powered by a sony 18650.


Heres what its doing. If I point it at the ground and focus it to a dot it looks just fine. If I shut it off and the turn it back on pointing downward it still looks fine BUT if I then hold it horizontal and turn it on the dot gets that distinct wide oval shape and grows to 2+ inches in width. If I then turn it off point it downward and turn it back on its a small dot again. I can even then lift it to horizontal and it keeps its small profile?! :wtf:

I dont think its a focusing issue because the focus is very firm and solid and doesnt turn easily.

Any ideas?!

Sounds like the optic elements in your lens are loose.
Take out the lens and see if you can tighten the retaining ring that holds it together.

RA_pierce said:

Sounds like the optic elements in your lens are loose.
Take out the lens and see if you can tighten the retaining ring that holds it together.

Click to expand...

If its an aixiz lens, I noticed on a batch for 405 that I got
did not use any glue on the threads for that ring. I have
had a few with loose rings too.

With the 650 lenses they were always glued..

Wow good call. I havent fixed it yet but when I removed the focusing head it rattles and the only small pieces in it that would make such a noise are the lens. Any trick or re tightening the ring? Looks like a special tool is needed.

Fixed it. Thanks guys! I might have to put some lock tight on it to prevent this in the future. Im surprised it didnt have it already.

and yes Wannaburn it is a 405

Braddubya said:

Wow good call. I havent fixed it yet but when I removed the focusing head it rattles and the only small pieces in it that would make such a noise are the lens. Any trick or re tightening the ring? Looks like a special tool is needed.

Click to expand...

I see that you got it :beer:

A good item to have around for tightening those
and optics in general are needle tipped tweezers.

Not the electronics kind, a good pair from a local
pharmacy are good.

I raided my wife's girly goodies for mine

I use these, but mine are a fancy red. :crackup: