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January 8, 2004

The Music Recording MD Format Has Evolved into a Versatile Recording Media for the Broadband Era
"Hi-MD" Realizes a Maximum Recording Time of up to 45 Hours of Music, and Raises the Potential for Versatile Storage
January 8, 2003, Tokyo, Japan - Sony Corporation today announced the development of "Hi-MD," marking an evolution of the music recording MD format into a versatile recording media that also delivers PC data such as images and text file recording capabilities, while maintaining playback compatibility with the current MD products and ensuring copyright security.
Since the introduction of the first "digital audio" MD products that enabled random access and easy editing, Sony has provided users with a variety of MD compatible products for various applications such as home audio products, portable devices and in-car systems.
The MD format is licensed by approximately 80 hardware/media manufacturing companies. Cumulative shipments of MD media and compatible products are expected to reach approximately 1.1 billion and 80 million respectively as of the end of fiscal year 2003. (Data by Sony)
With the introduction of "Hi-MD," Sony is poised to meet the demands of a growing broadband era with a versatile media capable of recording a variety of content, such as music and images, while maintaining high quality sound and resolution.
By formatting an existing MD into the "Hi-MD" format, its density can be increased to almost double the current maximum capacity. In addition, a 1GB (gigabyte) "Hi-MD" disc has been newly developed, realizing a maximum recording time of up to approximately 45 hours of music by incorporating the first (*2) Domain Wall Displacement Detection (DWDD (*3)) technology
Since "Hi-MD" products will be compatible with current MD format discs, users will also be able to play back their existing MDs.
"Hi-MD" uses ATRAC3plus (*4) audio compression technology, which delivers high data compression while maintaining quality of sound. "Hi-MD" also enables linear PCM recordings, resulting in the recording and playback of CD quality sound.
"Hi-MD" uses the File Allocation Table (FAT) system, which enables the recording of music and other PC data files such as images and text.
"Hi-MD" incorporates OpenMG and MagicGate (*5) copy protection technology. In addition, "Hi-MD" music recordings preserve encryptions contained within the original source.
"Hi-MD" users will be able to record various content, such as images and text files in addition to music, to a single disc and replay it on the go, at any time and any place. This makes it possible, for instance, for users to record their favorite music from their home PC to disc, play it back with their "Hi-MD" player while commuting to work, and to then connect it to a PC at work to upload stored content such as text files.
Sony will proactively promote the "Hi-MD" format industry-wide and anticipates that it will significantly contribute to the vitalization of legal music distribution. Sony will develop the MD market further by using its versatility as a recording media to explore new applications.
Through modification of modulation and error correction methods, and greater signal processing efficiency, high-density and high-capacity recording has been achieved. By formatting existing MDs into "Hi-MD" format, disc density can be approximately doubled (up to 300MB approximately in the case of an 80-minute MD). Furthermore the 1GB "Hi-MD" disc is the first of its type to incorporate Domain Wall Displacement Detection (DWDD) technology, leading to a maximum recording time of up to 45 hours for music data.
Domain Wall Displacement Detection (DWDD) technology:
The size of readable recording marks on an optical or a magneto-optical disc depends on the spot size of a laser. Until now, it has been necessary to reduce the spot size of a laser beam in order to read out small recording marks for increasing the disc's recording density. DWDD applies a kind of Magnetic Super Resolution (MSR) technology that utilizes the temperature variation created by an irradiating laser on a disc surface in order to temporarily expand recording marks smaller than a laser beam spot and read out the stored information.
"Hi-MD" incorporates ATRAC3plus high compression and sound quality audio compression technology, realizing extended length, near CD quality sound. By also adopting a non-compressible, linear PCM recording, "Hi-MD" compatible products enable users to enjoy the recording and playback of high-quality sound, equal to the quality of commercial audio CDs.
"Hi-MD" uses the FAT file system, making it possible to use "Hi-MD" formatted MDs and 1GB "Hi-MD" discs as versatile media for recording PC data files, such as images and text. Furthermore, as portable, rewritable PC media, "Hi-MD" complies with USB format's Mass Storage Class, ensuring that simply by connecting a "Hi-MD" product to a PC it is immediately recognized as an external storage device.
To prevent an illegal copying of digital content, "Hi-MD" incorporates OpenMG and MagicGate technology, already adopted in Memory Stick and Net MD for content management to ensure that music content stored on a "Hi-MD" disc will be encrypted. "Hi-MD" also conforms to the Serial Copy Management System (SCMS).
| Current・MD・format | Formatting・existing・MDs・into-"Hi-MD"format | Hi-MD-1GB・Disc | |
| Data-Capacity | 177MB | 305MB | 1.0GB |
| Laser Wavelength(λ) | 780nm | 780nm | 780nm |
| NA・of・Objective・Lens | 0.45 | 0.45 | 0.45 |
| Diameter | 64.8mm | 64.8mm | 64.8mm |
| Thickness・of・Substrate | 1.2mm | 1.2mm | 1.2mm |
| Tracking・Format | Groove・Recording | Groove・Recording | Groove・Recording |
| Addressing | Wobbling・Groove・(ADIP) | Wobbling・Groove・(ADIP) | Wobbling・Groove・(ADIP) |
| Data・Modulation | EFM | 1-7RLL | 1-7RLL |
| Data・Detection | Bit・by・Bit | PRML | PRML |
| Bit・Length | 0.59μm | 0.44μm | 0.16μm |
| Shortest・Mark・Length | 0.83μm | 0.58μm | 0.21μm |
| Track・Pitch | 1.5μm | 1.5μm | 1.25μm |
| Data・Transfer・Rate | 1.25Mbps・@1.2m/s | 4.37Mbps・@2.4m/s | 9.83Mbps・@1.98m/s |