Electronic Circuits and Projects Forum

i stumbled across this video on youtube: the video (sorry to those of you using dial-up, if you want to you can wait for this video to load or you can try this similar site: the site) what i want to know is who do these people think that they are fooling??? (if this is for real then i guess that they are fooling me ) i just find it a little hard to believe that you can make a burning laser just by damaging a single part in the laser pointer.

The movie shows clearly how not to do.

First I wonder about the terminus technicus "5Mw". 5mW would have been the appropriate "name".

Disassembling the laser pen the batteries should be in first place (Imagine what will happen to your eyes when twisting the laser diode cap and inadvertantly push the button with the laser pointing at you?)

I guess its doable to increase the laser power output. I also guess he just burnt the current limiting resistor to achieve a lower (or zero) resistance.

I furthermore guess the movie stopped at the point when the laser had reached its self-destruct point.

Observing the huge light pattern I think using a better collimator lens will have the same effect - with the difference of a longer life time of the laser diode.

Power laser diodes don't have a built in monitor diode just for fun.

Boncuk

Funny. This isn't the first thread that's linked that same video it's been around the net a few times, or at least one identical to it. I agree with pretty much everything Boncuk said. The dial he adjusted with the screwdriver was part of the feedback control for the laser although I'm not entirely sure what component he 'disabled' with the soldering iron, wouldn't a resistor go to a higher value not a lower one when overheated? Not really sure. It will definitely increase power, and definitely decrease lifespan if not outright destroy the laser module if done incorrectly. I'm also a little skeptical of how fast the match went up after the adjustment, if it were that high powered the camera lens should have been nearly over powered with the reflected light coming from it. I like the different color of the green lasers and the super bright ones are nifty because they can be seen in air in a dark room or at night but I never quiet understood the fascination with igniting matches. Considering how far down in cost green laser modules have come if you really wanted to play around with one I'd say go for it.

I recalled mugumbo with his classic quote "all you people replying to this thread are idiots". If he comes here again let's bash him!

What? Why Vizier?

Hi Sceadwian,

as with most things in life you'll have two choices.

Burning a metal film resistor it might cause a dead short or be a perfect isolator.

Burning too fast and at high temperature makes it a way it can't be used to increase power of the laser diode, since the metal film will evaporate turning it into the latter of the two possibilities.

Metal film resistors have a negative temperature coefficient other than carbon film resistors.

Applying the right temperature and amount of heat will decrease its value forever. (In circuit resistor trimming, as used by a japanese electronics component manufacturer)

I'll try to get a datasheet of those trimmable resistors, just can't remember the company name presently.

Regards

Boncuk

Thermally trimming resistors, hmm nifty =)

You can just remove the circuit from the laser diode and drive it with any DC power level you like, no need for silly circuitry mods.

But just like a LED there is a very limited range of power you can get out of one before it just burns out.

Originally Posted by Sceadwian

What? Why Vizier?

haha....
building laser from dvd burner diode

I signed up for these forums just to say this.
All of you responders of rotor's main question are idiots.