Super inefficient M140.

[Blackwolf]

I built a 1W blue laser again. It is the same as my last build (DTR m140, three element lens, 1.25A driver) but it seems to be horribly under powered or my other m140 is just super efficient.

Here is the raw output of my normal m140

here is the raw output of the other one

It is very spread out and there are only two bright areas. It also seems that


I did get this sweet beam shot

 

[Livinloud]

you cant tell if its inefficient just by the beam, it'd need to be LPM'd to tell the efficency

 

[NKO29]

I had one like this that I sold... Isnt that right Blaster haha I powered it at 1.25A and it only outputted around 800mW

 

[Blackwolf]

you cant tell if its inefficient just by the beam, it'd need to be LPM'd to tell the efficency

It burns with two fully charged 16340's at about the same pace as my normal m140 with one partially charged 18650 (buck driver). I cannot break through a black .53mm guitar pick in 15s. My normal one does it in like 1s. I wish I had a LPM but I am getting a 589 first.

 

[NKO29]

well i think a buck driver needs more voltage than the diode needs, so with only 1 cell it won't run at full power...

 

[DTR]

It is definitely damaged. I have seen damage like this and I bet if you varied the current different lines would light up and go out. You could try different currents and find the current that makes the most uniform pattern. I made a really nice 200mW pen build with a diode that was damaged like this and it ended up having very good divergence. If you have a bench supply you can slowly turn the current up and you will see different lines turning on and off. If you can find a level where it is the most centered and filled out that would be where you could run it for best performance. As for what causes this damage I am not sure but my guess would be a spike or something causing damage to the mirrors in the lasing cavity but not to an extent the diode goes full LED.

 

[daguin]

The zombie apocalypse is upon us

Peace,
dave

 

[Elektrotechniker]

prolly too much heat during soldering dem pins

 

[jander6442]

prolly too much heat during soldering dem pins

this:cryyy:

 

[Blaster]

I had one like this that I sold... Isnt that right Blaster haha I powered it at 1.25A and it only outputted around 800mW

Yes that exactly right when looking at the output from the diode no lens that's very similar to what i get a messy looking non solid rectangle, and the output is indeed 800mW constant on the dot at 1.25 A with 2 cells measured on my LPM i compared it to my other blues to make sure the LPM was working OK and there outputs where same as they have always been so a sad diode but a nice host ,hence a considerablely lower purchase price

 

[Elektrotechniker]

this:cryyy:

 

[Blaster]

Yeah well 800mw is pretty sad for a m140 but solid at that doesn't drop off, i could put a G2 lens and boost measured output to about 1025 mW ish, but i have three others higher so this is way it is i can barely notice the difference between the two 1165 mW blues i have, great host still plenty power enough, but a hug would help ....but as said i got it at a considerable discount after talking with the owner and got a nice refund back because it is underspec, still ppl its Not easy getting high power stuff in Australia so you really have to take within reason what you can get your hands on .

 

[sinner]

Definitelt "that" , I salvaged an m140 from an old laser i built, it was doing 1.3W at just 1.25,A. ? While building it into another laser i resoldered longer wires and with a new 1.8A driver the build was just giving me 1.1W... Same diode, higher current, less lasing.. It is either the soldering damage or while pressing it to the module it was overpressed..

 

[Blaster]

I'm sure there's other sad m140 stories based on low output, its previous owner didn't have a LPM to check output so didn't know when sold laser, we are both in Australia obviously ...from the original asking price i got 40% refunded on mutual discussion. Based on it had to put out 1.2 watts at least ....so that's why I'm not really worried, 800mW solid output in nice krypton grove host that glows blue when its been in the light long enough ,plenty of other ppl would be happy with that in Australia for sure,