first DVD diode smoke

[F4GRX]

As written in my presentation thread: last evening I improved my constant current driver to the point I felt it was safe enough to power up a laser diode (I previously made lots of tests on a set of LEDs).

I powered my 18x burner diode (pressed in an aixiz mount), it lased at 72mA; I quickly reached 100mA. Nice beam, but can I do more? The beam did not start to fade so I increased the current again and went up to 200 mA.

the diode: who in hell invented capless diodes? This one has only ONE supah-tiny 1mil bonding wire, I don't know how it can handle 200mA, and I was close to destroy it several times before I pushed that in a mount!



Then I used a magnifying glass to focus the beam to < 1mm.

I could burn black heat shrink tube and electrical tape!


I made a crappy video, will upload it later.

Wow, that was awesome, that was the first time I burnt something with a laser And it was all DIY!

that was ~500mW (200mA x 2.46V) of electrical power. What is the efficiency of a laser diode? :thinking:

But what surprises me is that the diode does not seem to heat at all :thinking:

 

[BoskoSLO]

Do you have a laser power meter?

 

[F4GRX]

Hi,

no, absolutely not

I tried an OPT101 light meter from TI, but it's not very usable, it was saturating with normal light from a bulb, or my circuit was crappy.

One of my next projects is to build a photodiode-based meter (using a BWP42).

I don't have access to photopiles, they is nothing useful on ebay and I don't like the fact that a photopile's output depends on the ambient temperature and attached heatsink properties. So I will use them only if I'm forced to do so

edit: I just have something like that http://cgi.ebay.fr/Lot-de-2-cellule...seaux_Autres&hash=item564654dc28#ht_647wt_869 but I read somewhere that these were not suited to build a LPM.