After 8 years of hard slogging the folks at InPhase are ready to ship the world’s first holographic storage system.

As StorageMojo noted 2 years ago:

InPhase is claiming they will ship drives with removable holographic disks with 300GB capacity and 20Mbps transfer rate later this year.

I love holographic technology and wish InPhase the best, but I don’t believe they have a viable business with their technology – yet. The problem: 3.5″ disk drives will reach 750GB by the end of this year with much faster transfer rates. InPhase’s 20 Mbps is only 2.5 million bytes per second or only 9GB per hour. It will take over 30 hours just to fill one disk! I predict that hard drives will still be more convenient and fairly cost-competitive than this promising new technology.

But keep at it guys. Lightning will strike if your investors are patient enough.

So what’s different now? They’re saying they will ship next month instead of “later.” The transfer rate is 20 MB/sec. And the media archive life is 50 years – higher density and longer life than tape.

Limited availability until fall
I saw a unit – not sure it was functional – at NAB last week. Marketing VP Liz Murphy gave me the pitch, about 110 seconds of which you can watch here:


The yellow plastic on the drive is for display purposes. Note the nifty see-through media.

Target market
As befits a small company with an $18,000 holographic drive whose media is quantity 1 $180 a copy, InPhase has a sharp focus on people who need a 50 year archive life. Like film studios, whose film-based archives are bulky and subject to the vagaries of physical chemistry.

The media price is reasonable – compared to Blu-ray. NewEgg has TDK 25 GB blu-ray media for $17. 12x that – to get 300 GB – is $204. Plus the clutter. The burners are cheaper though.

Why did it take 8 years?
InPhase had to literally invent almost every piece of the system.

  • The optical media.
  • The manufacturing process for fabricating thick, optically-flat and high-dynamic range media.
  • The mathematics and circuitry needed to use digital camera CMOS chips for high-speed and high-accuracy image reconstruction.
  • A new method – polytopic multiplexing – for a 10x density increase.
  • Holographic mastering techniques for commercial reproduction.

For example, in order to use commercial, l.e. affordable, CMOS optical sensors to read the holograms, InPhase engineers had to do a deep dive (pdf) into optical information theory:

For holographic data storage it is advantageous to limit the spatial bandwidth of the object beam to only slightly higher than the Nyquist frequency of the data pattern. Typically an aperture in a Fourier plane is used to band limit the data beam (thereby also minimizing the size of the holograms in a Fourier-transform geometry). The data pattern may contain at most 1 cycle/2 data image pixels, so that the Nyquist frequency of the optical field of the object beam is minimally 1 sample/pixel. However, since the spectrum of the irradiance pattern is the auto-correlation of the spectrum of the optical field, the Nyquist frequency of the detectable signal is actually 2 linear samples/pixel minimum. Thus any method relying on less than 4 detector elements/data image pixel is operating in a sub-Nyquist regime where the Nyquist rate is defined with respect to the actual irradiance pattern impinging on the detector.

As Liz noted, you can’t hire experienced holographic storage engineers. InPhase has trained every one of them.

The StorageMojo take
Kudos to InPhase for a magnificent achievement. This is comparable to IBM’s original RAMAC disk effort back in 1957. They all deserve to get rich.

15 years ago a 3x CD reader cost a few hundred dollars. Perhaps in 15 years holographic burners will be $50 and the media less than a $1.

Learn more about the technology at the InPhase Technologies web site.

Comments welcome, of course. See a more accessible version of this article on my ZDnet blog, Storage Bits.