My Monster 6+ watt Laser Build Has Started !

I did burn the AR coating on one of my 25mm scavenged projection tv lenses, it was with the raw output of a NUBM06.

All the things we want to do are possible, and I'm still learning about lenses, but correcting the rapidly diverging axis first and then using an expander is the way to get a tight spot at longer distances, my moped muffler build reaches out and makes a tight burn with some splash, but the burn is tight, I may just build an uncoated expander and eat the loss, it will be worth it. :beer:

I am surprised you burned a projector lens that large with just the raw output, even if a NUBM44. Wow, some of those coatings just aren't meant for much power, I suppose projector lenses are a given, but the one I used with my NUBM44 didn't burn. However, the back side of it did burn my hand from a reflection out of it when pointing my laser into it, could get someone in the eye and blind them, dangerous stuff if not wearing goggles. If you take the output of that laser diode and put it into a large diameter PCX lens, you can adjust the focus to turn the beam into a point 30 feet away, in that case it isn't expanded, but instead focused to a very fine point. The larger the lens diameter, in general, the smaller you can focus the beam into a point, especially for short wavelengths like blue.

Edit: Then you don't need to correct the beam shape, it is focused down to a tiny point, no issues. What I'd like to find the answer to is how small of a point can the beam be focused into at a great distance with a 3 inch diameter PCX lens. I can't experiment out here where I am at to find out, no lasers with me to do that with right now. I'd like to see a ratio of lens size to its ability to focus to a point at different distances. I better start googling now, but I believe the larger the lens or shorter the wavelength for a given lens diameter, the further away the beam can be focused into a small spot.

Yes, I have long been a fan of longer focal length lenses for our MM diodes, but the rectangle grows as well until you clip it, at long range if you have a spot 90% of that line is clipped.

We cant get completely around that horrible divergence with just round lenses unless you want a long thin line at distance, now if it's a tiny long line OK, but we are talking big lenses....I think we did the math on this before.

Optimally we would use a FAC lens at the emitter made of fused silica or quartz that could stand that energy density, then correcting a basically square propagating beam is easy, but if uncorrected then over distance, even with much longer FL lenses the ratio of that square/rectangle gets forever wider compared to it's height, until it clips the inside the optics by hitting the devices walls or simply falling of the ends of the lens.

The real question for us and more so for me is what's cost effective, one day I will buy a well used but still strong industrial material processing ytterbium fiber laser with excellent beam specs and lots of watts, and then I will be able to scare myself while melting through steel plate across my property, but until then I will do my best to make lemonade out of repurposed projector bulbs.

Now I am not too proud to do my wood burning art with a 2 foot wide lens on a contraption wired to my backpack full of car batteries, but I still want to possess the knowledge of how I would make it HH with the latest-greatest if I had the means.

BTW have you seen the Rick and Morty cartoons, I wish they would make a new season, those guys are great. I will be the crazy old mad scientist, absolutely. :beer:

Have never seen Rick and Morty cartoons, I will take a look. Melting through a steel plate, unless a razor blade with a YAG pulse probably isn't going to be in my future but I have a lot of other things I can work on with these parts I've been gathering. I will use the ones I like the most first, probably sell off the others later. If you are into burning things, I think you built the best of both worlds with your 3X expander, working to produce both low divergence when focused to infinity as well as the ability to focus the beam into a point

I will probably stop buying toys soon, have enough to work with, next is learning more about lasers so I can better use the technology to do what I want to do with them.

Mo power is mo better, I agree, that power in a small point awesome.

I recently made a rick cue for my rgb projector!!

I need to learn how to make gif files, I know it will be simple, just never have, a R&M gif for my avatar would be cool, I can think of many, maybe a new one each week.

RedCowboy said:

I need to learn how to make gif files, I know it will be simple, just never have, a R&M gif for my avatar would be cool, I can think of many, maybe a new one each week.

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Red, check these online pages, I've used them before, just can't remember which ones exactly.

Free Online Animated GIF Maker - Make GIF Images Easily
Online Animated GIF Maker & Editor - Create and Edit GIF Images Easily
https://ezgif.com/maker

and one that you can make anim .gif from your youtube files.
https://giphy.com/create/gifmaker

These all came up on Google search, I just can't remember which ones I've used in the past, I've even done them in Photoshop but it gets a bit tedious that way.

RB

RedCowboy said:

CLICK>>>> 2pc ?30x?25mm Aluminum 6061 Round Tube OD30mm ID25mm Any LengthTubing Tooling T6 | eBay


NOTE: When you sand and test fit parts be sure to have some thermal grease on the parts so they don't seize together or you may destroy then trying to get them apart, you can rotate gently as you assemble to find a natural mate but if you feel it start to grab at all twist and pull it apart right away so you don't seize, at least you have 2 dissimilar materials, copper/aluminum, if it was copper and copper that would grab like mad.

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The tubing will be here tomorrow, Free shipping and it got here pretty dang fast !

lasersbee said:

:na::na::na:
Mmmm I can smell the pizza......

Jerry

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:crackup::crackup::crackup: don't forget the beer!:friend:

10fenny said:

I recently made a rick cue for my rgb projector!!

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Doing the Rick dance? LOL
or Everybody get swifty
I was watching reruns and they changed the part where he called government workers mindless drones and they changed Get Swifty to some BS.

hehe the look like from back to the future doc and Marty op:

Alien Laser said:

hehe the look like from back to the future doc and marvin op:

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Marty.

:yh:

thanks

Accutronitis said:

The tubing will be here tomorrow, Free shipping and it got here pretty dang fast !

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USPS tubing was a no show :wtf: Maybe tomorrow :thinking:

Nice your getting the 44 i just ordered the 07E/and 7475 for my collection
Imagine the mail man placed your laser module in the neighbors mail box and tomorrow you wake up and see your neighbor shining a nice blue laser and your still waiting for it !!! :thinking:
--- :can: ---

Alien Laser said:

...i just ordered the 07E/and 7475 for my collection
Imagine the mail man placed your laser module in the neighbors mail box and tomorrow you wake up and see your neighbor shining a nice blue laser and your still waiting for it !!! :thinking:
--- :can: ---

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... and imagine further, that same neighbour shining your nice powerful new blue laser at Your face....

:cryyy: :crackup: