• Coelacanth@feddit.nu
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    1 month ago

    Ah, that’s what it was! I always thought it was just a different color for 0 and 1, today I learned! That makes more sense when I think about it.

    • 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.