Researchers at the University of Shanghai for Science and Technology have developed an optical disc with a capacity of over a petabit of data, equivalent to well...
Optical discs are already incredibly resistant and shouldn’t be expected to fail in your lifetime. Most of the times they do, it’s either old media (cd and dvd both had physical flaws in design), damage, or mistakes in manufacturing.
There’s really no reason for the discs to degrade. It’s just stamped plastic.
When they say plastic takes [huge number] of years to decompose, they’re talking about how long it takes to disappear completely. The usable lifetime for most plastic objects seems to be only a few decades. (I don’t know about the specific plastic they use for optical discs, though.)
As an optical media enthusiast, I’ve done a fair amount of research into how, why, and when discs fail. Because the discs use two or more polycarbonate layers pressed together, moisture can sometimes work its way between the layers and speed up degradation, especially if a disc has been overly flexed at the center. Heat and UV can also speed up degradation.
Another problem is that plastic is petroleum-based and it breaks down over time. A lot of people think that the reflective layer (the metal layer) is actually the data layer but it almost never is. The data layer itself is polycarbonate, sandwiched between the reflective layers and more polycarbonate layers.
The newer discs like blu-ray movies are made with better plastics that should last at least 100 years. Depending on the dye layer of writable and rewritable blu-rays, they should last either at least 25 years or 100 years.
Pressed optical discs will last a very long time. The lifetime of burned discs depends on the type of dye that’s used to store the data. Many of the early CD-R’s would get corrupted after a few years, but that was solved a long time ago.
Optical discs are already incredibly resistant and shouldn’t be expected to fail in your lifetime. Most of the times they do, it’s either old media (cd and dvd both had physical flaws in design), damage, or mistakes in manufacturing.
There’s really no reason for the discs to degrade. It’s just stamped plastic.
When they say plastic takes [huge number] of years to decompose, they’re talking about how long it takes to disappear completely. The usable lifetime for most plastic objects seems to be only a few decades. (I don’t know about the specific plastic they use for optical discs, though.)
What disc is left? blu ray?
Bluray and uhd bluray are the current standard
The foil coating usually deteriorates first
On cds, yes. Technology from the 80s, designed in the 70s.
As an optical media enthusiast, I’ve done a fair amount of research into how, why, and when discs fail. Because the discs use two or more polycarbonate layers pressed together, moisture can sometimes work its way between the layers and speed up degradation, especially if a disc has been overly flexed at the center. Heat and UV can also speed up degradation.
Another problem is that plastic is petroleum-based and it breaks down over time. A lot of people think that the reflective layer (the metal layer) is actually the data layer but it almost never is. The data layer itself is polycarbonate, sandwiched between the reflective layers and more polycarbonate layers.
The newer discs like blu-ray movies are made with better plastics that should last at least 100 years. Depending on the dye layer of writable and rewritable blu-rays, they should last either at least 25 years or 100 years.
Pressed optical discs will last a very long time. The lifetime of burned discs depends on the type of dye that’s used to store the data. Many of the early CD-R’s would get corrupted after a few years, but that was solved a long time ago.