When the HDDVD-Bluray wars were going on China had their own implementations of optical storage, and it has been evolving ever since. Much of it is undocumented in languages other than Chinese.
Companies in China use these alternative optical discs, some of which store up to 1TB of data.
The only reference I can find to it on English Wikipedia is the CBHD
it's actually 128GB per disk (BDXL), I only know of Chinese companies announcements of 500GB optical disks last year[1], not sure if they are already deployed to some enterprise partners, it's entirely possible. Their more theoretical research goes far beyond that. [2]
There are archival storage machines similar to tape drive robots for archival storage in the Chinese market where you have hundreds of such disks in a single unit and 1PB+ per rack.
Companies in China use these alternative optical discs, some of which store up to 1TB of data.
The only reference I can find to it on English Wikipedia is the CBHD
https://en.wikipedia.org/wiki/China_Blue_High-definition_Dis...