260W IR Laser pump handheld?

[Borislav@87]

Hello. I have free time and decided to assemble a portable IR laser with a power of 260W. For this I will use this laser pump which needs 29V and 18A power. This is new to me so I'll probably need some help. I also ordered a compatible lens that mounts on the array and will probably have good focus at about 5-6 meters. In the future I will buy another one that can have a longer focus.. Everything will be in a box again. There will be cooling with a powerful fan and the array will be attached to an aluminum radiator. At the moment I have not selected a suitable driver and power supply. I will assemble a battery from 18650 cells. I have 30 quality cells. I haven't decided exactly which driver will power it. I'm wondering if I should use a step-down or step-up driver. I can also make two batteries with two rows of 6 batteries each at 24V and connect them in series for 48V. And to use a downgrade driver. Even at the moment I have several new ones from 600W, which according to specifications support 20A. Or I can buy a step up driver or one that has an input voltage of 12V or higher and can output 28V 20A.

DC converter step up 28V / 20A
I just found this on AliExpress:
BGN48.57 | 12V to 28V 13.8V 15V 19V DC power converter 12V to 24V 15A 20A 25A 30A booster DC-DC transformer module

https://a.aliexpress.com/_Eziyom0

Laser Pump
I just found this on AliExpress:
BGN63.12 | DMK MAX Raycus IPG original Laser Source Pump Source Diode Laser Generator Parts Full Power Laser Cannon For Laser Repair

https://a.aliexpress.com/_EItTZ3A

 

[RedCowboy]

Those appear to be marked 970-975nm so know what you are working with and use the proper safety goggles.
Even a cheap pair is better than nothing.

Goggles

 

[Borislav@87]

Those appear to be marked 970-975nm so know what you are working with and use the proper safety goggles.
Even a cheap pair is better than nothing.

Goggles

Yes, I will be very careful. I decided on step-up drivers, as the accumulator that I will make again will be 24V from 18 pcs 18650 batteries. I also ordered the one from 1200W, but I am leaning towards the one from 28V /20 A. I don't know if these 2A in addition will not damage the laser. I see that the specifications give it a maximum of 19.8V and 18A. That is, at 28V per driver, it cannot take these 20A current.

I just found this on AliExpress:
BGN19.34 | 1200W 20A DC Converter Boost Step-up Power Supply Module IN 8-60V OUT 12-83V With Heat Sink 1200 W 12V to 24V 48V 1200W 20A DC

https://a.aliexpress.com/_EwhnGiC

Also an option is to use two drivers connected in parallel. Because I have one of those 600W each that I use for NUBM37 and NUBM38.

 

[Borislav@87]

I bought another one with a power of 120W. Powering it will be easier

 

[LightSourceBlue]

Good luck with the project, something I've considered before but not gotten around to!

The IPGs look like good options for a handheld, since they weigh less and apparently have a higher efficiency ratio than some of the Chinese brands - they seem to be going for a decent price recently as well. The 120w are also a decent weight, so a good option as well.

Will you be removing the fiber optic cable and going straight through to the lens (I have seen the lens you posted a photo of be used at the end of a fiber before)? Otherwise you will likely need to cleave & polish the fiber - which is always a lot of .... fun!

 

[Borislav@87]

Good luck with the project, something I've considered before but not gotten around to!

The IPGs look like good options for a handheld, since they weigh less and apparently have a higher efficiency ratio than some of the Chinese brands - they seem to be going for a decent price recently as well. The 120w are also a decent weight, so a good option as well.

Will you be removing the fiber optic cable and going straight through to the lens (I have seen the lens you posted a photo of be used at the end of a fiber before)? Otherwise you will likely need to cleave & polish the fiber - which is always a lot of .... fun!

I can't say anything about how it will happen yet. So far I have not dealt with such laser pumps. My goal is to collect everything in a box like the ones I use so far and have an adjustable focus. I was recommended a similar lens from a photo camera 420-800mm, which is very cheap ($55) The fiber will probably have to be removed and I will have to put a lens on the front with an adapter. But like I said, let them arrive first and see what it's all about. There will be a secret key, a 12V fan converter, a temperature display and other small things

 

[Borislav@87]

I received the 260W pump yesterday. It was connected to the fiber. I had to remove it. I cut it at the bottom, but then the problem happened. When turned on, the tip that brings out the fiber started to light up. So this tip had to be removed. When tried, it broke and stayed inside. I disassembled the pump and saw that the beam was coming out through a small hole. It was clear what I had to do. I had to drill a new wider hole. But that was a problem. The glass tip was not broken. He was ruining the drill when he tried. We took the massif on a lathe and with a milling cutter I reduced the diameter of the pump by about 5mm until. From there, with a larger drill, we drilled very slowly until the glass tip disappeared. Then with a smaller drill we made a new hole. Now everything is as it should be. The beam now goes directly outside. Now there is a focus about 3-5cm in front of the pump. After that, it expands quite quickly. I don't know what lens to buy for a longer focus.

 

[Borislav@87]

I don't know why, but no lens I have can focus. What is this due to? It's like putting a regular glass in front. I have an actively glued lens with a focal length of 1250mm. I put it in front at different distances, but I can't get a beam. It's like I didn't put anything in front. Where am I going wrong and do I need to buy special lenses that are for the laser spectrum?

 

[Gryphon]

Looks like you still have the fiber focusing optics in place, they are focusing the beams down to a pin point where they would have entered the fiber and are now just diverging rapidly outside of the module because the fiber is gone

 

[RedCowboy]

You want to use a concave followed by a convex and make the convex adjustable so it can " zoom "
Like this:

Also you may need to remove the optic ( everything past the pbs cube ) that launches the beam bundle into the fiber and make the exit hole in the housing wider.
p.s. Remember to always lase safely.

 

[Borislav@87]

@RedCowboy

Yes, after the cube there are two lenses that focus the output. Only with this lens that I found, a good beam is obtained. I ordered a 9mm lens for Infrared. If I remove the two lenses that are in front of the cube, I will have to drill a large hole in the front for the wide beam to pass through. These days I'm going to drill out the 12mm hole and pop in this 9mm lens adapter. That way I will be able to adjust the focus with a wide variety of lenses. And about the big lens test, I tried double concave then double convex but no results. Nothing happens. It's like lenses don't refract rays. With my blue ones, the laser works, but not here.

 

[RedCowboy]

Try your 9mm lens 1st and see what you get.

If that doesn't work then you need to remove the fiber launch optics past the pbs cube....then use a concave and convex to zoom to focus at range.
Understand you are focusing a cluster of knife edged beams so you won't get the same beam quality as an active fiber system, because what you have is a pump ( there can be hundreds ) used in an active fiber system..... speaking of which, active fiber systems are becoming much more affordable and in the years ahead they will become more compact.

Actually I would like to see the size of the pumps ( could be integrated ) in the latest consumer fiber systems, if these prices continue to come down, I'm going to have to get one.

In 5-10 years we will have portable laser welders the size of a cordless drill..... we going to have to push laser responsibility and hold the careless accountable, actually I hope eye safe systems in the 1550nm plus range are developed for the coming consumer market.

Prices are coming down > Look

More compact > Look

*** REMEMBER TO USE PROPER LASER SAFETY GOGGLES ***

 

[RedCowboy]

Ahh I see your video with the 9mm lens, looks good.

You may want to use a NON-coated lens if the VIS-AR coating starts to burn if you can't clean it, of use a NIR-AR coated lens.

 

[Borislav@87]

@RedCowboy
Yeah, I'll try what happens with a 9mm lens first. Also when the new one arrives. Before that I need to put the pump on the lathe and slowly drill a 12mm hole because it is currently 6mm. If it doesn't work, I'll buy that camera telescope and give it a try. With it, I was told that good focus is obtained at long distances. I received the other 120W pump today. It is quite small and costs $45, and the 260W one costs $100. However, the same thing happens in a test. Fiber backwards melts, if I run more current it lights up. I don't know what this is due to. What should I cut it with, how long should the core be from the outer layer. The one from 120W I can see that it does not open, test I can not see how it is arranged inside. If I want to remove the fiber I don't know how it will be done. I'll probably have to cut the protruding part off entirely

 

[RedCowboy]

The Fiber burns backwards because the cleaved fiber end must be polished, otherwise it will burn.

You can buy fiber polishing supplies online, but for your purpose removing the fiber should work better.

 

[Borislav@87]

The Fiber burns backwards because the cleaved fiber end must be polished, otherwise it will burn.

You can buy fiber polishing supplies online, but for your purpose removing the fiber should work better.

I think I stopped the ignition. With a mock knife, I rubbed where it burned. But that doesn't work for me. If possible, give a link to the tools for polishing such fibers