hi everyone
i have a laser diode that has been taken out from a cd rom (32x) i want to use it to make a pointer and have no idea ho to even get started
i have connected 3 wires to the terminals of the laser diode even after giving a 12 volts supply i does not seem to light up
please some one help me soon
SOS

 

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hgmjr (moderator)

 

The diode is probably emitting in the near IR, which makes it invisible. You can use a digital camera to see if it is emitting. The CCD imager is sensitive to near IR.

You might also have fried the device by not limiting current through it. Here is the relevant article from out Ebook - http://www.allaboutcircuits.com/vol_3/chpt_3/12.html.

 

tripplegravity,
Most CD/DVD player lasers will emit light outside of the visible spectrum, as has already been mentioned. This in itself makes them unsuitable for laser pointers.

Power supplies for lasers have to be very accurate in order to avoid subjecting the laser diode to even momentary excess current. If too much current passes through the laser diode, even for an instant, it will be destroyed. To properly set the current through the diode generally requires (at a minimum) documentation on the diode.

What has not been mentioned as of yet is the danger associated with these diodes, particularly in recordable-type CD/DVD drives. If you don't know what you're doing, you can become blinded or otherwise maimed within moments.

Even commercially available low-powered laser pointers output more than enough light to cause blindness if used in a careless manner; for that matter so can the newer "super bright" LED's.

You only get one set of eyes per lifetime. Protect them.

 

hi everyone
i have a laser diode that has been taken out from a cd rom (32x) i want to use it to make a pointer and have no idea ho to even get started
i have connected 3 wires to the terminals of the laser diode even after giving a 12 volts supply i does not seem to light up
please some one help me soon
SOS

12 volts, through a 2-4 volt, sensitive device... Guessing you will have a lot of trouble getting any use out of it, now... Should have googled 'laser diode hookup' first. There is one very good page, 'Sam's (something..)' which would have saved the part (maybe, no specs, and easy to fry...).

 

I suspect the blue ray lasers are going to be very popular for their color. We might get ready for the inevitable queries about them.