My First laser Test:Successful!!!

[deltawars]

This is my first laser it isn't finished yet but i wanted to share it.

I used a 1.5w 808nm laser diode(One extra high burning power (1000mW-1500mW) 808nm TO-5 9mm laser diode + Gift* | eBay) and surprisingly it was bright red!! When i was asking question about lasers everyone said i shouldn't use a 808nm diode because its IR(Annoyingly you can't see the red at all because the IR overpowers it so i will try to get a IR camera filter.).

I'm using a LM317T constant current driver at 1.3A to drive the diode, it is meant to use 1.6A so i worked out it was running at %81(1300W/1500W)(just waiting for the right resistor value to be delivered).

All i really have to do is mount the laser and driver and in a torch case so it can be a handheld laser but i have to find a torch big enough for the laser,driver,battery and switch.

Some pics and vids:
I was using a 12v 3A power supply test the circuit, the voltage regulator and driver got really hot so i didn't leave it on too long.

This is just the LM317T constant current driver that i made.

The datasheet for the diode says 2.5v max input so i used a voltage regulator to drop the power supply from 12v to 5v that got really hot as well(i know your going to say but wait you said 2.5v max input, well the diode came with a free 100mw which said 2.5v max input and i stuck 7V thru that and it survived also someone told me that it really doesn't matter about the voltage but i just wanted to take it down closer to the 2.5v).

And this is basically the whole setup i used to test the driver and diode.

Here is just a video of me burning some stuff with the laser.



And i would also like to thank Daedal for his laser driver tutorial://laserpointerforums.com/f42/diy-homemade-laser-diode-driver-26339.html

Sorry for the bad picture and video quality there wasn't enough light where i was standing and i couldn't be bothered to move lol.

 

[Npglaserer]

If you can get your hands on some wavelength changing crystals...

:lasergun:

 

[Wolfman29]

Be careful with that diode. It looks red because we can see a little bit of IR, but looks can be deceiving. What you see as a sort of bright red is actually a LOT of IR power (ours eyes are not very sensitive to it, so we perceive it as dim). So just a fair warning. This is still very dangerous.

 

[deltawars]

:O wavelength changing crystals i like the sound of that but i looked around on the internet and can't find any can you please tell me where i can get some?

And thanks for the heads up Wolfman(+1 rep ), i noticed when looking at the beam thru camera compared to real life it looks a LOT brighter on the camera screen(as they can see IR).

 

[CheesyWalnut]

What was the gift you got from ebay?
Just wondering

 

[CheeseHasLeafs]

If you can get your hands on some wavelength changing crystals...

:O wavelength changing crystals i like the sound of that but i looked around on the internet and can't find any can you please tell me where i can get some?

You'd be looking for neodymium doped YAG, and KTP. Pumping the first with your 808nm laser diode would give you 1064nm IR light which would be doubled int he KTP crystal to give 532nm green.
Don't you just love wikipedia?

And what Wolfman said. I think eyes are sensitive down even into 1064nm, as long as it's bright enough. It'd appear a deep, dim red, but in actuality is a very bright IR light. I think clear polycarbonate blocks IR light, so those'd be easy to find.

Oh yeah, and look at this if you're interested in the 'wavelength changing crystals'
http://laserpointerforums.com/f45/do-yourself-complete-green-dpss-o-like-crystals-42495.html