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Do DVD drive lasers Have colors? Answered

my question is : do the lasers in dvd drives have colors, for example blue ore red, or are they invisible at naked eye?
thank you all for answering!

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frollardBest Answer (author)2011-04-18

CDs use an infrared laser invisible
DVDs use a red laser ~600nm visible
Blu-ray uses a violet/blue laser ~405nm visible

Source: http://en.wikipedia.org/wiki/Optical_disc

The diodes in all of the above can be removed and repurposed as visible lasers but you'll need focusing elements/lenses if you want a collimated beam, because the optics in the drive are designed to focus to a tiny point a few mm away from the lens.

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steveastrouk (author)frollard2011-04-20

....and AFAIR, the beam is naturally eliptical ?

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frollard (author)steveastrouk2011-04-20

Many are indeed based on the geometry of the crystal used in the diode.

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Vyger (author)2011-04-18

You can remove the plastic front of the drawer usually by unsnapping it. If you do that and then put a disk in you will be able to see that its a red laser, usually.
Blue Ray drives use ultra violet which is a much higher frequency light so it can read more data. Hence the name.

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