• MeThisGuy@feddit.nl
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    1 month ago

    CD - red laser

    BlueRay - blue laser… shorter wavelength --> more data on same size disk

    and inbetween there was DL - dual layer
    light scribe - could etch a picture on the top of the cd
    and RW - rewriteable CDs

    (CD is short for compact disc)

    • Captain Aggravated@sh.itjust.works
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      1 month ago

      CDs like laserdiscs before them are read with an infrared laser.

      DVDs use a red laser, and Blu-ray does indeed use a blue-violet laser. The smaller wavelengths, plus the ability to do multiple layers, are indeed how they cram more data more densely onto a disc of nearly identical size.