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Professional Disc

From Wikipedia, the free encyclopedia
Professional Disc
Media typeOptical disc
Capacity23 GB per layer
Developed bySony
UsageData storage
Released2003; 21 years ago (2003)

Professional Disc (PFD) is a digital recording optical disc format introduced by Sony in 2003 primarily for XDCAM, its tapeless camcorder system. It was one of the first optical formats to utilize a blue laser, which allowed for a higher density of data to be stored on optical media compared to infrared laser technology used in the CD and red laser technology used in the DVD format.

Technology

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PFD uses a 405 nm wavelength and a numerical aperture (NA) of 0.85 for the laser, allowing 23 GB of data to be stored on one 12 cm disc – the equivalent to nearly five single-layer DVDs, and a 1x speed data transfer rate of 88 Mbit/s for reading and 72 Mbit/s for writing. After the 23 GB disc was released, a dual-layer 50 GB was developed and released.

This format is sometimes confused with the Blu-ray Disc format, another optical disc format using blue-violet lasers and supported by Sony. Even the PFD's caddy and Blu-ray's original caddy (later dropped) looked very similar. Capabilities differ; single-layer PFD discs have a capacity of 23 GB whereas Blu-ray discs can store 25 GB. However, Blu-ray discs currently allow a 2x data transfer rate of 72 Mbit/s – lower than PFD. This is because PFD discs use much higher quality media and drives use higher quality components, making them prohibitively expensive for the consumer segment to which Blu-ray is aimed. PFD discs can have a capacity of up to 100 GB for rewritable discs, and 128 GB for write-once discs.[1]

Disc Sizes

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Disc Size (GB) Disc Color Layers of Disc Storage Time (minutes record using HD422 50 Mbit/s) Properties
23 Black Single 45 Rewritable
50 Red Dual 90 Rewritable
100 Yellow Triple 180 Rewritable
128 White Quad 240 Write once

Applications/products

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19-inch racks of Professional Disc decks at Fuji TV
Professional Disc camcorder Sony PDW-510
Professional Disc camcorder Sony PDW-510

XDCAM video system

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The PFD format is used as the recording medium in Sony's XDCAM professional video devices, both for standard definition and high definition applications.

Professional Disc for Data (PDD)

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Professional Disc for DATA (PDD or ProDATA) was a general-use recording media variant of PFD, aimed primarily at small and medium-sized enterprise for data archival and backup. PDD drives and media became available in mid-2004. The BW-RS101 external SCSI-3 drive originally retailed in the UK at £2,344 (excl. VAT) directly from Sony, and 23 GB write-once and re-writeable media retailed for £30 each. Two other drives – the BW-F101/A internal SCSI drive and the BW-RU101 external USB 2.0 drive also became available around the same time.

On March 31, 2007, Professional Disc for DATA reached their "end of life".[2] PFD are still being manufactured and used in Sony XDCAM devices. Sony states that PDD and PFD media are not compatible,[citation needed] but does not specify the exact differences between products.

Sony's PDW-U1 Professional Disc drive is an external drive that connects via USB 2.0 to Windows or Mac OS X computers using the included free software from Sony. In a firmware and software upgrade in late July 2009, Sony added the ability for computer users to store any computer files on the Professional Disc into the dedicated "User Data" folder.[citation needed]

See also

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References

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  1. ^ "Professional Disc (Single, Dual, Triple & Quad Layer) - Sony Pro". pro.sony.
  2. ^ "Sony Global - Professional Disc for DATA". Archived from the original on May 31, 2005.
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