TDK recently demo’d an impressive technical achievement: a 10 layer optical disk with 320 GB capacity – using standard Blu-ray (BD) drive technology. Each layer has better than 90% light transmission and writing required no more than 20 mW of the 30 mW Blu-ray spec.

Too bad it will never be a commercial success. Optical is at the end of the line.

When do formats die?
When their combination of reliability, capacity, performance, density and cost aren’t competitive. Which is where optical is now – even 320 GB optical.

Some of you may remember punched paper tape – hot in the 60s and early 70s – and popular on 16 bit minicomputers back when 4k of RAM was respectable and 64k unaffordable. It was limited to a few dozen KB of capacity and unreliable in long-term use, so when 240KB 8” floppies arrived in 1973 paper tape was toast.

Floppies had to improve to compete with removable disk pack drives – like DEC’s RK05 family – with their 2 MB capacity and a screaming 150 KB/sec transfer rate, and floppies did by increasing capacity – what TDK demonstrated – and decreasing size, from 8” to 5.25” to 3.5”, and cost from over a thousand dollars for a drive to less than $20.

But floppies couldn’t keep up with the growing size of applications and data sets. The 100 MB Zip drive was insanely popular when introduced in 1994 – a woman offered me a $100 premium on the spot to buy mine at a Palo Alto sushi bar – but by 1999 the format was on the way out thanks to cheaper and more capacious CD-R drives.

Despite heroic efforts to increase removable magnetic disk capacities – culminating in 2001 with the 5.7 GB Orb drive – removable magnetic disk media is dead, killed by cheaper optical and more convenient flash media.

Removable: backup and transfer
Removable media has 2 major use cases: data backup and data transfer. Tape dominates removable media backup today with capacities rivaling the largest disks.

Thumb drives long ago replaced floppies for smaller file transfers – “sneakernet” – with external hard drives handling large capacities. With 1 TB 2.5” hard drives, even a writeable 50 GB Blu-ray (BD-R) can’t compete with a small hard drive in transfer speed or capacity.

TDK’s problem
Which gets us to the 10x Blu-ray problem: even if it were commercialized there would be no market. Why?

  • Capacity. Successful optical media capacities have been competitive with current disks – CD-ROM in the early 90s; DVD-R in the early 2000s. Multi-layer Blu-ray will never be more than a small fraction of hard drive capacities.
  • Performance. 24x Blu-ray transfer rates are half that of today’s disks. And as capacities increase, disks get faster. Not so with Blu-ray.
  • Reliability. Early adopters report that BD burner disks often don’t play on many commercial players. That will get fixed someday, but multi-layer DB-R will have to solve it again.
  • Density. Managing a single piece of media is much simpler than managing 6 or 10. External hard drive density makes them much more convenient.
  • Cost. BD-playing DVD drives haven’t been popular on PCs, and BD burners are way more expensive, as is the media. A FireWire or USB 2 or 3 hard drive can be had for less than $100, has much faster access times, higher capacity and faster data transfer. With volume BD-R costs will come down – but where will the volume come from?

Multi-layer BD-R has advantages, especially if current BD players can be updated to use it. But there is no commercial justification for distributing content on 320 GB optical disks and there isn’t likely to be one.

Hollywood has a real chance to make 3D work this time, but 3D HD movies will fit fine on BD. Put a 3D “Band of Brothers” on a single disk? OK, but really, getting up every 50 minutes to change disks isn’t so hard, is it?

The Storage Bits take
New optical formats will get introduced – like 750 MB Zip drives and 5.7 GB Orb drives – but they’ll stumble around the fringes of consumer acceptance before a quiet death off stage. Many of the same forces that are killing BD – downloading, upconverting, cost – are closing in on optical media in general.

DVDs will be around for years – even as CDs still are – but the focus is shifting to online storage and local disks. The industry still hasn’t cracked the code on massive home disk storage, but that day is coming.

You’ll buy HD 3D content online, download it, store it in your digital library, and watch it when and where you want. If your house burns down your content suppliers will let you download again. Who needs the hassle to burn disks?

The one remaining piece is for hard drive vendors to get serious about building archive-quality hard disks. I love their technology, but they aren’t the most forward looking group.

Courteous comments welcome, of course. Anyone interested in buying a vintage USB Zip drive?