Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers



Laser Pointer Store

did i burn my diode?

alfadex

New member
Joined
Feb 9, 2012
Messages
21
Points
0
Hello, i have problem ,i found a laser diode from dvd plextor 16x i make the circuit with lm317 i ,i put 6 volts and the mA was about 180mA
http://www.youtube.com/watch?v=RHwV6vveyfs&feature=youtu.be



and i was waiting to start burn ,i didn't know that i would use a lense to focus the light so i put voltage 12 volts, the mA goes to 250 ,but i let to 250 mA just for 5-10 seconds, it was hot but not so much and now


and now happens this .....

http://www.youtube.com/watch?v=kYk9kkMtJAU&feature=youtu.be

i put 7.2 volts the mA are 200-215 mA the diode is hot if i let it for about 10 seconds ,buttt the light is very small, i does not light as before, why?? I burn it?

tnx
 
Last edited:

Sigurthr

Well-known member
Joined
Dec 11, 2011
Messages
4,382
Points
83
You LED'd it.

1) you're not using a heatsink.
2) you put too much voltage through it, 8V should have been the absolute maximum IF it was heatsinked. Extra voltage gets turned into excess heat.
3) you put too much current through it.

You put three watts of power through a bare red diode and expected it to live. You can't put three watts through a hardy M140 bare diode and expect it to live. Do some reading here on how to DIY, not YouTube. Get an Aixiz module (which has a lens, lens holder, and is a heatsink (but not enough for high power)) and build yourself a constant current driver.
 

alfadex

New member
Joined
Feb 9, 2012
Messages
21
Points
0
Yes you are right, i do some mistakes i put too much voltage and current and i mess it up. But for the heatsink i didn;t place one,because i use it for a few seconds ,just for test. That diode from dvd plextor how many watt is? i am electrician and i have great knowledge from electronics but i din't know how diodes works!! Now from this site i have learn many many things.
But ther are tonsss of information here and i lost my way,
so I want to make my own a red laser, not portable,i will construct my own heat-sink i want to be about 200-250 milliwatts, which one reliable diode must i buy and which one lens to use ?? i prefer 650 nm but it is not a problem

Of course i know i have to buy googles
LASERS AREN'T A GAME!!!
 

FreeBee

New member
Joined
Feb 12, 2008
Messages
85
Points
0
i am electrician and i have great knowledge from electronics but i din't know how diodes works!!
Gee, you could have done some minor research though. Laser diodes are very similar to normal light emitting diodes, apart from their output, wattage, voltage, and current. They generate lots of excess heat you need to get away from them as fast as possible. And as an electrician, you should know you can't just turn up the voltage dial for 'just a few seconds' expecting nothing to break. You'd do that to a LED?

Anyway, I'd suggest you try again with some cheaper diodes from old DVD drives. They might not always burn, but it'll help you learn to understand the laser diodes better. Always try to look for information about that particular diode, and you know the max current you can send through it. Good luck!
 

sinner

Well-known member
Joined
Oct 27, 2011
Messages
2,571
Points
83
Unfortunately , yes u burnt it!
It happens, so no need to worry.. you are on the right track atleast. Welcome to lpf..
This forum will help u a lot.
If u need any help we are here to answer the question, please use the search button first, That will let u find more useful information already answered and u wont have to wait for others to reply on your thread. Saves time,
Good luck!
 

alfadex

New member
Joined
Feb 9, 2012
Messages
21
Points
0
thanks for all! Before i try to make a laser pointer and afterward to destroy it,i couldn't believe that there would be a forum like this and sooooooo many people work on lasers! I was reading the forum 3-4 days and i learn many many things, i will try with lpc826 and when i construct my work i 'll release it here:yh:
 

alfadex

New member
Joined
Feb 9, 2012
Messages
21
Points
0
Hello i am here again, i get an lpc-826 ,i made the circuit with lm317 and i place 1 ohm resistor ,i put 7.2 volts but the maximum miliamber i get was 300mA, so i burn a paper and after 30 seconds i see some smokes.The axis is adjastable and i get a good sign at 20cm.It is really hot after 1 minute, what am i doing wrong now? look here

video 2012 03 06 20 50 10 - YouTube

The circuit i make was from here
Laser driver - It can be done
 

Blord

New member
Joined
Dec 24, 2007
Messages
5,368
Points
0
Why would you want to put 1.25A (1250mA) thru the LPC-286 ? Did the diode survived ?
 

Ghostchrome

New member
Joined
Aug 14, 2011
Messages
1,155
Points
0
I think he was saying that he used a 1ohm resistor for a test load, to get his driver to 300mA?

Anyway, the diode gets hot because the it needs to be heatsinked better. One minute is way too long to be running at 300mA just using an Aixiz module.
 

sinner

Well-known member
Joined
Oct 27, 2011
Messages
2,571
Points
83
Thats because of the Cheap Breadboard.. Their connections are really inadequate hence u should try to solder all of the stuff on a good quality strip-board..

What resistor did u use between V-out and V-Adj Pins on LM317?
Also try to find a LOW Dropout Voltage Regulator like LM1084 to 1086
OR Super LOW Dropouts LM1584~1587
LM317's are outdated although they are reliable as shit!!
The new ones have additional protection circuits built in and they are bit more efficient.
 

alfadex

New member
Joined
Feb 9, 2012
Messages
21
Points
0
i made again the circuit from the begining and i have exactly the same results!

http://imageshack.us/f/18/img0459rl.jpg/
Afterwards i place 2 18650 batteries full charged ,it was about 8.31 volts . The resistor between Vout and Vadj at lm317 was 5 Ohm and the maximun amber i could drive the diode was 240mah. Then i place 3 ohm resistor at lm 317 and the amber was 285 mah. The potensiometer was 40 Ohm . I have see other people ,that was using lm317 and drive the diode at 430mah. I cannot understand what is going wrong
 
Last edited:




Top