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My Furst Custom laser 7W+ NUBM0E

WizardG

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Is it possible to put the laser through a fiber cable, come out the other end, and compress the light?
Sadly, the laws of physics won't let us get a tighter beam that way. If you want your '44 to have a tighter beam you'll need to invest in a cylindrical lens pair or some anamorphic prisms.
 



GeramyL

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No, a length of fiber will not improve your lasers coherence length, it will make it worse.....unless you are pumping an active fiber gain medium such as double clad doped fiber, but it's not a simple process.

Let’s just take for example the fiber lasers made by CloudRay or Raycus they make 1075nm I believe láser sources then they output the light in a cable and put that cable in a laser head which then outputs the light with lenses and such. Is that not possible with the 445nm diodes? The fiber cable should refract the light and come out nearly the same as it entered right?
 

RedCowboy

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No your light out of the fiber will be less collimated.

Also the 445nm multi mode laser diodes have uneven divergence, that is it's not a Gaussian beam like a dpss 532nm, it's a rectangle shaped beam with the fast axis divergence being much greater than the slow axis, that's the 1st issue you must overcome if you want a better beam.

Single mode fiber has a much smaller inner dia. but multi mode fiber has a much wider inner dia. which adds to the issue, but the Raycus fiber laser uses double clad fiber with the inner fiber being doped with elements such as erbium and ytterbium making it a gain medium, this is called active fiber.

In an active fiber laser your pump sources contained by the outer core drive the inner core gain medium which produces a high quality beam.

Fiber-laser-Single-clad-double-clad-fiber-600x268.jpg


 

GeramyL

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No your light out of the fiber will be less collimated.

Also the 445nm multi mode laser diodes have uneven divergence, that is it's not a Gaussian beam like a dpss 532nm, it's a rectangle shaped beam with the fast axis divergence being much greater than the slow axis, that's the 1st issue you must overcome if you want a better beam.

Single mode fiber has a much smaller inner dia. but multi mode fiber has a much wider inner dia. which adds to the issue, but the Raycus fiber laser uses double clad fiber with the inner fiber being doped with elements such as erbium and ytterbium making it a gain medium, this is called active fiber.

In an active fiber laser your pump sources contained by the outer core drive the inner core gain medium which produces a high quality beam.



Not to sound dumb but can’t you use a FAC Lense to help? I have been thinking CO2 laser or 450nm laser source box. I really like the 450nm high output lasers. I was also seeing that you can get the beam down to about 0.08mm square
 

Unown (WILD)

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GeramyL you cannot make a false quote with someone elses name. Edit your post or it gets deleted. This is your first warning
 

Borislav@87

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New body with a smaller radiator.
NUBM0E 455nm
5A driver
Average 6.5/7W
 

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Borislav@87

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I used this new Chinese laser according to the information from the seller, it has a real power of 2w. So I decided to do a test with my LPM meter and see what it would show because many posts said it doesn't measure accurately. You can see in the video that this $5 LPM meter does a great job and is fairly accurate.
 

RedCowboy

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Meter calibrated by Chinese laser pointer advertised output.........That's a joke.....right ?

Your " supposed to be a 2W " Chineseium laser pointer is not a known quantity, testing it proves nothing as per your meter accuracy, it could be a 1w laser or a 1.5W is more likely, why not test something that we know what it should do ?

Test a M-140 @ 1.8A with a G2 lens and we should see close to 2W
Test a NDB7875 @ 2.3A with a G2 lens and we should see close to 3W
Test a NUBM44-V2 @ 4.5A with a G2 lens and we should see 7.25 - 7.5W
Test a NUGM03 @ 2.1A with a G2 lens and we should see 1.2W

Test a sharp 405, test an osram pltb450b, test something we know because what Chinese makers advertise or print on a laser sticker is meaningless and more often than not inaccurate.
 

Borislav@87

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Meter calibrated by Chinese laser pointer advertised output.........That's a joke.....right ?

Your " supposed to be a 2W " Chineseium laser pointer is not a known quantity, testing it proves nothing as per your meter accuracy, it could be a 1w laser or a 1.5W is more likely, why not test something that we know what it should do ?

Test a M-140 @ 1.8A with a G2 lens and we should see close to 2W
Test a NDB7875 @ 2.3A with a G2 lens and we should see close to 3W
Test a NUBM44-V2 @ 4.5A with a G2 lens and we should see 7.25 - 7.5W
Test a NUGM03 @ 2.1A with a G2 lens and we should see 1.2W

Test a sharp 405, test an osram pltb450b, test something we know because what Chinese makers advertise or print on a laser sticker is meaningless and more often than not inaccurate.
No other laser diodes available. This Chinese laser is marked with a power of 5000mw, but the real one is about 2W. I'm not saying it's 100% meltable, but it's fairly decent, and for this price, every hobbyist should have it. I bought this Chinese laser for a friend. From what I tested when focusing it was able to light a stick of wood fairly quickly. At the moment I only buy NUBM0E diodes because they provide excellent power output at 5.2A for this price. I have already sold 3 300 euro lasers with this diode and everything works great. Currently waiting for 2 more diodes to arrive. And relative to their power, I see that it is unglued with each diode. Some are stronger than others. I had a single unit that I had shared in a previous post under the same conditions it showed 1.5W more than the others. But all the ones I put at 5.2A show 7.2 - 8.5W on my device with a 3 Element lens.
 

RedCowboy

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But all the ones I put at 5.2A show 7.2 - 8.5W on my device with a 3 Element lens.
Then your meter is reading about 50% higher than it should be, with a 3E that reading should be around 5 - 5.25W at the best........ 7.2W is what you should get with a G2 lens and 8.5W would be with no lens at all and from a cold start testing a brand new diode cherry picked and even then I have my doubts, but with a 3E lens @ 5.2A nope, it's 5.2W that you will get with a 3E @ 4.5-5.25A and pushing them any harder than 4.75A is just making more waste heat.

If you had a lab quality meter and tested 2 identical diodes with the same lens, you would see the diode driven @ 5.2A would show diminishing returns faster compared to the same @ 4.5A and @ 3.5A in a good heat sink you wouldn't have any heat fade, your power reading would be steady.

We are overdriving the nubm0e even @ 4.5A because the heat bottle neck is in the diode, but with a good lens and heat sink you can squeeze max output for a minute or two, however all the time the output is slowly ticking down so pushing from 4.5A to 5.2A just isn't worth it unless you employ active cooling or keep your duty cycle really short, but 8.5W with a 3E is pure fantasy from a de-canned nubm0e @ 5+ amps, even from a freak diode.......maybe with a G2 lens from a freak diode and a cold start, but a 3E ( 3 element ) lens.......it's fantasy.
 

Borislav@87

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Yesterday I received a new NUBM0E diode, which turned out to be bluer than the others. Probably 460nm+. I can't judge, but the color of the blue is different and I like it a lot. Even the beam itself is brighter than the others. It is possible that they sent me another diode. However, the power is like the others and my meter shows identical power to the others at 5.2A
 

nmbusa

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Yesterday I received a new NUBM0E diode, which turned out to be bluer than the others. Probably 460nm+. I can't judge, but the color of the blue is different and I like it a lot. Even the beam itself is brighter than the others. It is possible that they sent me another diode. However, the power is like the others and my meter shows identical power to the others at 5.2A
really like it a lot or just a little, scale from 1-10 would help "a lot"
 

Borislav@87

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Well, the difference is not huge, but it is there, and I like the blue better
 

Borislav@87

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Time came for me to come across a faulty diode NUBM0E as well. I put in a brand new diode and after a few tests on the laser it started to glow dimly. When first switched on, it glows brightly and after about 10 seconds, its power weakens a lot. Everything else is like my other lasers. I thought it was a faulty driver, but I tried another one and the results are the same. The problem is in the laser diode.
 

Borislav@87

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Hello. I want to ask if the lack of soft start is bad for the diode. I have a driver that has lost the weak and flashing mode and only has maximum, but when starting, as far as I can see, the soft start is also missing. I will mount the NUBM44 in this large copper body.
 

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