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Sony's Double Density CD-RW Drive Reviewed
Boone^ writes: "Sony's newest CD-RW, the Spressa CRX200E-A1, is actually a DD-RW, meaning that it (re)writes on DD media that's capable of 1.3GB of data storage using the new Purple Book standard. Sony adapted the ISO 9660 format, but they narrowed the track pitch from 1.6 to 1.1 microns and shortened the minimum pit length from 0.833 to 0.623 microns. I found some benchmarks of the new drive on CDRLabs.com. So, is this just a technology hack until DVD-RW prices come down? This drive seems like a steal with a $250 USD sticker compared to the recordable DVD options." If it's on Pricewatch, it's not vapor anymore. You may have to look around a while for the double-density media, though -- and if that doesn't catch on, you'll be glad it's also a regular CD-RW drive.
... you could buy the drives from a tiny handful of vendors (check), for about 3x the money (check), with media prices only eight times higher than the 1.44MB counterparts (check), and of course they weren't readable on the massive installed base of drives (check).
And after you went to all that trouble, your stack of 600 floppies was now... only half as high! 300 floppies!
If 700MB isn't enough, then 1.xGB won't be that great, either. Certainly not enough of an improvement to throw away compatibility and incredibly low commodity prices. If this sells more than a token number of units, I'll eat my shoe.
cheers,
mike
I'm still waiting on the consortium between the NSA, IBM, Microsoft and Sun to form so I could have a 1gig chip implanted in my head that plugs into any outlet which is connected to a 1terrabit drive created by clustered Clariion's which stores the data in my head for STORAGE PURPOSES ONLY thank you.
;)
Want Root?
Where can I get a hole punch that will convert my regular CDRs to DD-CDRs?
-Peter
PS: It's a joke. If you don't get it just move on.
-P
Before we keep flaming sony for not adhereing to a standard (which is true in a lot of cases), the new drive does adhere to the proposed (and I believe certified) Purple Book specification. Now if wether or not someone else will adopt this, I don't know...
--The space between my ears was intentionally left blank--
Actually, I was one of the people in a group who worked on this technology (not at C3D -- don't know who they are, at another company).
.8 nm pits (around 800MB-1 GB per layer). We were able to limit interference by way of a kind of two-photon absorption to select the layers and spot-test the data by measuring the amplitude of a specific spot on the disc when an absorbing wavelength (presumably) was emmited.
The photochrome is called bacteriorhodopsin, which is a seven helices protein with an attached retinal molecule. It's about 4 nm long. When exposed to 570 nm (yellow-green) light, it starts a cycle of definable photointermediates which vary from a few fractions of a picosecond to tens of milliseconds. There are also several latched or nested photocycles which can remain transient for years. Some genetic variants even have the capability to run several photocycles at once. It's quite a remarkable molecular engineering feat of nature via natural selection of billions of years fromthe tiny blue-green bacterium H. salarium (used internally for photosynthesis via proton pumping over the cell wall and internal membrane).
Our group was able to create a bR coated CD which had over 500 layers of
The BER (bit error ratio) was around the rate of CDs, and with error correction, it was almost a usable mass storage drive. We attempted to get production funding, but we could only create a few working models for a few highly specilized companies mainly because of the cost of the laser. As I mentioned, bacteriorhodopsin is controlled by wavelength, and we needed at least 3 different wavelengths corresponding to the absorption maximums of the different photointermediates. This means blue (400 nm) for erase, yellow (570 nm) for page select and red (675 nm) for write/read.
In our experiment, we used a single laser for all three wavelengths and we used optical parrametric ossciliation and frequency doubling/mixing to get the three colors using crystals, and we used a Q-switch to change colors in less than a few microseconds (e.g. access time). This was fairly complicated although the use of discrete components and a diode pump laser made the optical assembly as small as a large laser pointer. It was still costly as it required special optical crystals to do the OPO and frequency stuff. Currently, these crystals are expensive in low quantities, cheap in moderate quantities and expensive in high quantities because it is difficult to grow once the crystals get so large, and it isn't economical to grow tiny batches. For production, of course, we would need very large quantities and thus the drive wouldn't be cheap enough for the consumer market.
There are alternatives, for example. A pure semiconductor solution utilizing multi-color diodes would be optimal. There is a company currently producing blue laser diodes, and soon green, but these are still expensive and don't have a high life. So, fundamentally, we were limited by other technologies.
Currently, our group does have a production license from a major storage manufacture and we are developing a storage and processing device based on bacteriorhodopsin in solid form in sol-gel (aerogel) suspensions. This looks the most promising and it will be affordable to commercial markets as other solutions which provide the same features are much more expensive and have a much large footprint. We're likely to market to large datacenters and companies with lots of data which needs to be online in a fast and associative system, and where space is a concern.
I really think there is going to be some great things in terms of storage technologies as soon as diodes and VCSELs bridge into more wavelengths (read: WDM will force this) and have faster switching times. As it is, we're only using a fraction of the several hundred thousand terahertz bandwidth of even a single wavelength, let alone more than one. Optical is definatly the way to go.
Pretty cool stuff, especially when you see a movie playing off of something which was once only a thought and a proof-of-concept few bits in a lab.
"I'll just chip in a bit for RedHat: I actually have that installed on my university machine." - Linus, '95
Rats. I was holding out for the Blue With Pink Stripe Book standard.
Or maybe Bluish Green With a Hint of Yellow Book.