Hot on the heels of the most successful storage mediums of all time — MiniDisc and Zip disks — Sony has announced the Optical Disc Archive, a system that seems to cram up to 30 Blu-ray discs into a single, one-inch-thick plastic cassette.

The cassettes will range in capacity from 300GB to 1.5TB, but beyond that very little is known. Conventional dual-layer Blu-ray discs store up to 50GB, but the newer BDXL spec allows for up to triple- (100GB) and quadruple-layer (128GB) discs. Basically, there’s somewhere between 3 and 30 discs in a single cassette.

The drive itself is a specialized unit (the cassettes won’t fit in your PC’s Blu-ray drive) that will connect to a computer via USB 3.0. Actual read/write performance of the drive is unknown, as is the price. 12x Blu-ray burners max out at around 50MB/sec, though, so we could be talking about performance comparable to hard drives — and it’s possible that Sony will debut a device that’s even faster than 12x, too. The first Optical Disc Archive cassettes and systems are scheduled for a fall 2012 release.

As far as we can tell, the main selling point of the Optical Disc Archive is, just like MiniDisc, the ruggedness of the cassettes. Optical discs themselves are fairly resistant to changes in temperature and humidity, and the cassettes are dust and water resistant. What is the use case for these 1.5TB MiniDiscs, though? In terms of pure storage capacity, tape drives are still far superior (you can store up to 5TB on a tape!) In terms of speed and flexibility, hard drives are better. If you’re looking for ruggedness, flash-based storage is smaller, lighter, and can easily survive a dip in the ocean. Due to the specialized hardware and bulky cassette, it’s unlikely the platform will ever compete on price, too.

I can see the Optical Disc Archive filling two niches: quickly transporting large amounts of video across rough terrain; and providing extensible backup for multimedia devices, such as video cameras and TV PVRs, like TiVo and Sky+. Hard drives fill up pretty quickly, and high-density cassettes make a lot more sense than burning single DVD/Blu-ray discs. Unless Sony can get other companies to make and sell ODA drives, though, it will probably just go the way of the MiniDisc.

Read more at Sony (press release), or read about Sony’s latest round of lay-offs and its attempt to revitalize itself

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