Those totally look like the isolinear chips from Star Trek

  • @Evil_Shrubbery@lemm.ee
    link
    fedilink
    1
    edit-2
    7 months ago

    CD-ROMs are read-only(-memory) & usually stamped plastic covered with mirror-ish surface (aluminum-somethings prob?).

    CD-R have an (recordable) organic layer on top you can burn lil patterns into, once only.

    CD-RW can be re-written several times.

    But none of them really last long.

    • ChaoticNeutralCzech
      link
      fedilink
      17 months ago

      Many pressed CD-ROMs and audio CDs will likely last over 100 years if stored properly. However, the tolerances in the standard are high so lots of manufacturers use cheaper materials and processes than intended while still producing discs with the CD logo. It will take decades before we really know which were worse than others. The most likely point of failure is delamination, which will leak air between the layers and oxidize the aluminum coating in a process named laser rot after Laserdiscs, the earliest commercial optical disc system.

      Anyway, the longetivity of (re)writable CDs is indeed usually below 20 years.

      • IONLYpost
        link
        fedilink
        1
        edit-2
        4 months ago

        The recording layers of the CDDAs (1983-1987) had already vanished. So they lasted no longer than 40 years.
        "SHM-CD"s would probably meet that 100 year mark but DVDs made them pointless by the time they were first released.

      • @Evil_Shrubbery@lemm.ee
        link
        fedilink
        17 months ago

        Yes, storage is very important in the long run.

        And music industry indeed had some of the thiccest disks afaik.

        • ChaoticNeutralCzech
          link
          fedilink
          17 months ago

          No, it’s not about the thickness. Most of it is clear plastic anyway, the data layer is only in the top few dozen micrometers. Also, all CDs and later 12cm discs were 1 mm thick by spec.

          • @Evil_Shrubbery@lemm.ee
            link
            fedilink
            17 months ago

            Yes, I am talking about the top layer - some are def thiccer and more scratch resistant (I didn’t mean thicket like you would notice looking at it from the side).