how to easily focus any gball diode without deccaning(tutorial)

[deadshadow]

hello everyone i decided to make a small and quick tutorial about all the latest diodes with gballs and how to properly focus them because i have read alot of comments from members that don't even buy or want any gball diode because tend to degrade after deccaning,well you don't have to deccan it :shhh:

1st of all sorry for the pure image quality and not any mesuring methods but the whole testing was very quick,if any further discussion and mesurments needed i can do that later.

for the testing i grabbed a nubm05 diode that was way out of focus with the original gball diode intact,this diode make a very big square box in 10 meters.

you can clearly see the box output although i captured the "dot" 2 meters from the diode.

my diode is mounted on a desktop heatsink and powered from a psu,so 1st step you just have to screw a common G2 lens BACKWARDS ( i know on the image it is not backward but i took the pic before realising that make a bad output that way)
the ring you see on the image is cut from a standard 5.6mm diode housing and i just need its m9x0.5 threading to connect the 2 lenses.

i screw the G2 lens till it hits the gball's metal frame and here is the unfocused output you get( my lens is a bit dirty i know)

this output is just like any output from diodes without a gball so now we only have to focus it as normal.

i used a 3 element lens for the testing but any lens can work as normal,even a G2 if you can stand the divergence.

simply screw the metal threaded ring and after that the 3 element lens(or any lens),it will look like this

here is the output we used to work with :bowdown: (edit:at this time i realized that i had to use the 1st lens backwards and changed it,the photo taken before i fixed it and that's why have so much splash around it)

screw in you last lens and focus it as any other diode

lastly here is the output perfectly focused,as you can see the "out of focus box" is gone and can focus your diode as normal even for burning.

it is very important to screw the G2 lens backwards else you will have some awful wings or dirty dot on your final output. hope this helps everyone that want to have gball diode focused perfectly without 1-2 months lifespan :beer:

edit: the m9x0.5 threading ring that used from standard brass housing is working but in case of a 3 element usage as 2nd lens it would be better a little longer ring due to long focal lengh of the 3 element lens it is on edge of the threads almost fully unscrewed,a little bit teflon can help for more secured and tigher threadings also.

 

[RedCowboy]

Ahh, you put the G2 in backwards, interesting, I have a couple of NUBM42 diodes and another NUBM06 coming on the slow boat, I will give this a try when they get here as my surviving 06 GBalls have a pretty good set focus that I use with 3XBE and that's a strong burner as the GBall is efficient and the natural divergence of the 06 is stage 2 like the NDB7A75, but adding the 3E is worth the loss to preserve the lifespan of the less focused GBalls.

I will also try G2 ( backwards ) + G7 + 3XBE and see how well that works. :beer:

 

[lasersbee]

Interesting....
Thanks for the info and tests. :gj:

Jerry

 

[GSS]

Nice
Have you metered the power at any stage? There has to be some power loss?

 

[RedCowboy]

I know the GBall and G2 are very efficient, the GBall is basically a super efficient G7. ( longer FL single )

The 3E will eat up 30% or so but that's normal for the trade off, I wonder about using a previously removed GBall as its a longer FL after the backwards G2 ??? That might work even better than a G7 after the backwards G2.

So intact GBall diode with backwards G2 then a salvaged GBall set to focus, then a 3XBE if you want to, that should be less loss if it will fly.

 

[Alaskan]

Cool, you just found a way to relieve my concerns over buying a gball laser diode, this is great news for the 07E diodes which have short lives if exposed to normal air.

 

[deadshadow]

Of cource there are power loses but this has only to do with each type of lens,as RedCowboy mentioned 3 element lenses have big lost power,i have not metered the outputs on the testing but i already own a nubm08 build that does around 6w out of the gball and after this method with 1 G2 and a 3 element im getting a pick power of 4.7w. i bet with 2 G2 lenses the losses will be only around 0.5w. 2x G2 lenses can work nice to fix a bad focused gball diode but will not lower the divergence like a 3 element does,different type of lenses are just a trade of between power and divergence.

RedCowboy im interested to see the results with your G7 lens,try it on a bad focused factory diode to see the results cleaner

edit: im also succesfully using G2+3 element+3x beam expander on my nubm08 and the spot size on the far field is similar to a ndb7875 divergence focused with a G2 lens but with 4.5w of power this build have run more than 10 hours in total and still works at full power.

 

[BowtieGuy]

Thanks for sharing your findings with us, this seems to be an easy way to focus while keeping your Gball lens intact.
Your 4.7W power output reading seems pretty good using this set-up.

RCB, or Chris, if you guys want to try this, and want a longer 9mm x 0.5mm coupler, let me know, I could tap a longer one for you if you don't have a 9 x 0.5mm tap handy.

Thanks for sharing, deadshadow! :yh:

 

[GSS]

Yup good stuff
So basicly the usual 10% loss of a G2 and 3 element 30%.
I was just wondering if the using multiple lenses changed the "ratio"?? when going through lens to lens.

 

[Alaskan]

That would be great Jeff, I don't know what length I will need, what ever you think would work well with the possible lenses we have would be much appreciated.

 

[deadshadow]

Cool, you just found a way to relieve my concerns over buying a gball laser diode, this is great news for the 07E diodes which have short lives if exposed to normal air.

yeah this was the main reason for the project,to make gball diodes more usable on our hobby.

Yup good stuff
So basicly the usual 10% loss of a G2 and 3 element 30%.
I was just wondering if the using multiple lenses changed the "ratio"?? when going through lens to lens.

could be a bit more,i can't remember exactly the the raw Gball reading,it was somewhere to 6-6.5w.still its usable with a pair of G2's if someone don't want that amount of lost power it will still have an adjustable focus gball intact laser

 

[cyberdoc]

yeah this was the main reason for the project,to make gball diodes more usable on our hobby.

Thanks so very much for sharing your wonderful fix with all our members! Kudos (and +Reps) for reminding us of the happiness that comes from helping others. Great Job, and Please Take Care. :gj:

-cd.

 

[paul1598419]

That is good information. I was hoping someone might try a concave lens after the ball lens to get it to diverge like an open can, then add the collimating lens. But, if this works, it is a solution. :thanks:

+ Rep.

 

[kecked]

Now someone make me a mount to hold it.

 

[RA_pierce]

I haven't read up on what the deal is with the blue-ball lenses so maybe one of you can clue me in...

Are these just super short focal-length collimators that are sloppily glued into the can?
I remember seeing someone (wish I remember who so I can give credit) doing a test of a bunch and finding that the output profile varies from diode to diode.
If the blue-ball lens is just a collimator, then we could potentially use a long focal length lens to focus the output from the blue-ball diode into a more familiar beam, right? This would result in much lower losses than re-expanding and then re-collimating the output (essentially a beam expander without expansion).

It seems to me that the blue-balls are a blessing in disguise - we just need to come up with a better optic mount standard than the teeny-tiny aspherics we always use.

Anyone have some blue-ball lenses to send me so I can experiment? :angel:

 

[Alaskan]

I've never bought a gball, but some members have purchased multiples and found some were nicely collimated, but others in the batch were a bit off of being fully collimated. My understanding is they are just short FL compression mounted lenses.