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1.5a or 1.8a

xxppslayer

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I'm building my first laser which has a 2w m140 diode. should I use a 1.5a driver or a 1.8a driver? I want it to be bright but I also don't want to fry it.
 



Giannis_TDM

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You absolutely shouldn't build your first laser with m140 2w is too much to start off with, I don't even know why Encap didn't tell you otherwise..... First, do build some lasers based on DVD diodes or a beautiful cyan sharp GH04850B2G or even a 515nm emerald-pastel green using the Osram PLT5 510.
 

xxppslayer

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You absolutely shouldn't build your first laser with m140 2w is too much to start offwith, I don't even know why Encap didn't tell you otherwise..... First, do build some lasers based on DVD diodes or a beautiful cyan sharp GH04850B2G diode from sharp or even a 515nm emerald-pastel green using the Osram PLT5 510.
I probably should've started off with one of the diodes that you mentioned, but I already got my hands on a dlp projector with an m140 array. I'm using laser goggles and doing everything thats needed for safety so I think I should be fine.
 

Giannis_TDM

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I probably should've started off with one of the diodes that you mentioned, but I already got my hands on a dlp projector with an m140 array. I'm using laser goggles and doing everything thats needed for safety so I think I should be fine.
If so please do build an LM317 driver and set the current to 400mA max first and use it for a bit as safely as you can(no ppl in the same room, don't shine at glass, metallic objects ect.) Only then should you even start to consider turning up the power
 

xxppslayer

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If so please do build an LM317 driver and set the current to 400mA max first and use it for a bit as safely as you can(no ppl in the same room, don't shine at glass, metallic objects ect.) Only then should you even start to consider turning up the power
alright, I'll get the 400 ma to 1.1 amp variable current driver from survival lasers and I'll set it to the lowest current possible and go up from there once I get comfortable with using it at that power. what output would I expect from that current?
 

Giannis_TDM

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alright, I'll get the 400 ma to 1.1 amp variable current driver from survival lasers and I'll set it to the lowest current possible and go up from there once I get comfortable with using it at that power. what output would I expect from that current?
few 100s of mw's
 

Lifetime17

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Hi X,
Ok the M140 is a great diode with nice beam profiles. At 1.8 A the M140 will do fine with a G2 lens . make sure you have a host with adequate heats sinking for the diode. being that you have a projector with the the array here are some pics .
The pic with the diode pinout shows the M140 markings , the diodes with the array without those markings are M140 A type diodes.
Those will be run at 1.3 to 1.5A and will do about 1.6 to 1.8 mW's depending on the efficiency of the diode it self.
Enjoy and be safe and take your time dont rush extracting the array.
After you have the array out of the unit use a heat gun to melt the indium solder to melting point to push the diodes out of the array.
Just watch how much het is applied , it will not take long to heat the indium to remove the diodes.
Rich:)
FA13817A-8890-4EE6-9E22-3B9CA28F974E_4_5005_c.jpeg7686C4BC-24C8-4E1F-80BB-76C1A9F924AD_4_5005_c.jpeg
 

xxppslayer

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also, the projector I bought was being sold for parts. chances are, most of the diodes will be fine right? sorry for all these questions, I'm new to the hobby.
 

Encap

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.... I already got my hands on a dlp projector with an m140 array. I'm using laser goggles and doing everything thats needed for safety so I think I should be fine.
alright, I'll get the 400 ma to 1.1 amp variable current driver from survival lasers and I'll set it to the lowest current possible and go up from there once I get comfortable with using it at that power. what output would I expect from that current?
If you scroll down on the link I gave you 400mA will give you an output of 474 mW and 1.1A will give you a 1.5W ouput or there abouts. Survival offers the adjustable driver in a 1.1A to 1.8A version also--same price if you want to try that one.

You say " I'm using laser goggles and doing everything thats needed for safety so I think I should be fine." if true then there should be no problem with whatever output you make.

You can read all about laser safety here--best web site on laser safety: https://www.laserpointersafety.com/
 
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Lifetime17

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also, the projector I bought was being sold for parts. chances are, most of the diodes will be fine right? sorry for all these questions, I'm new to the hobby.
Hi, Yes if the array is intact should be ok and that depends how many hours are on the projector. The XJ-m140 is a work horse.
Rich:)
 

thanhtung

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I'm building my first laser which has a 2w m140 diode. should I use a 1.5a driver or a 1.8a driver? I want it to be bright but I also don't want to fry it.
You can set it at 1.8A no problems with m140 diode
 




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