From the “Laser Disc” to “Blu-ray” March 2008
History of the optical disc
In 1958, 50 years ago, David Paul Gregg invented the first optical disc using a transparent disc technology. The disc was 30 centimeters in diameter and used an analog format and laser technology. It is therefore also called a “Laser Disc” He patented his design in 1961.
A later development of the optical disc were patented in 1969.
In 1967, David Paul Gregg's company, Gaus Electrophysics, contacted Royal Philips Electronics, but was met with disinterest. However, just a year later, MCA Discovisions purchased Gaus Electrophysis along with the patents for the optical disc technologies.
In 1969 Philips developed the technology to the design a laser disc using the reflective mode. This method had a great advantage over the transparent mode previously used and developed by Paul Gregg.
Philips and MCA decided to join forces in September 1974 and together developed the “optical disc”.
They announced the completion of their joint efforts and published the standards for the optical disc in 1967.
A number of Paul Gregg's patents became the basis of the optical disc technology.
MCA, who owned the patent to the reflective optical disc and Philips, who had been working with MCA, demonstrated the optical disc to the public in 1972. The name adopted for the first optical disc was “Laser Disc” or simply “LD”
The first available LD was marketed in Atlanta on December 15, 1978, with the players being manufactured by Philips and MCA producing the discs.
The Laser disc and a DVD
The LD was released two years after the VHS Tape system was introduced, and it could not compete with the growing popularity of the VHS.
The laser disc player sold only about one million units in the United States and approximately four million in Japan and the last LD released in Japan was the “Tokyo Raiders” in 2001.
The Laser Disc Museum gives some interesting history of the Laser Disc. See the link below:
One of the influential contributors to Audio, Video and Data recording, is Kees Immink.
Dr. Kees A. Schouhamer Immink was born on December 18, 1946 in Rotterdam, The Netherlands. He Joined Philips research laboratories in 1971.
His contribution to the technology of digital audio and video has enabled all of us to listen to audio and watch video on reliable, high quality media. Dr. Immink's coding methods are essential to CD's and DVD's. For a full biography about Kees Immink see the website:
The Compact Disc (CD)
The Optical VideoDisc, although a major development to be used in later research, was not a great success. I recently talked to a number of people about the optical Video disc, but they had never heard of it.
The Sony & Philips team was not idle, and building on some of the laser disc technologies, they set out to develop a new digital audio disc; in contrast to the earlier optical disc, which had an analog format.
In 1979, they set up a task force of engineers led by the prominent Kees Immink and in 1980, the group produced a Compact Disc Standard, called the Red Book.
Compact Disc formatThe Compact Disk uses a red laser to scan the patterns of bumps on a mirrored surface which are interpreted as bits. These bits can be assembled into bytes. A CD can hold about 700MB (megabytes) of information or about 80 minutes of music.
The Red Book gives detailed information on the design of the Compact Disc and was released in 1980 by Philips and Sony. It was adopted by the Digital Audio Disc Committee and ratified as IEC 908
The development of the CD was the combined work of a large number of scientists working as a team. The Compact Disc Story, written by Kees A. Schouhamer Immink provides a lot of background information. See the weblink below for the full story.
The CD, available on the market since late 1982, remains the standard playback medium for commercial audio recordings to the present day. Various formats of the CD were later developed. Some of the common formats are:
Audio files CD
Data storage CD-ROM
Write-once audio and data storage CD-R
Rewritable media CD-RW
By 2007 200 billion CDs had been sold world wide.
The search for a “super density” data storage continues.
The time was ready for a new way to play videos and provide a higher capacity disc to store data and programs. CD's were rapidly replacing the audio tapes and the VHS was coming to an end. Data often had to be stored on multiple discs.
Two teams were determined to produce a video disk to replace the VHS tape; the Philips & Sony team and Toshiba.
Philips & Sony started the Multi Media Compact Disc (MMCD) and Toshiba designed the Super Density Disc (SD). Notice the emphasis on each of these, “Multi Media” and “Super Density”. Both of these formats incorporated video and data capabilities.
Multi Media Compact Disc (MMCD) 1990s Philips and Sony
The MMCD was designed as a single-sided compact disc, with a single or dual layer. The capacity for a single layer was 3,7GB , compared with 7.4GB for the dual layer. It was backward-compatible with the CD and CDROM, however, it did not become a standard.
Super Density Disc (SD) 1990s Toshiba
The Super Density Disc (SD) was adopted as the standard format, with an addition of to two options, proposed by the Philips&Sony team. For more information see the section on the DVD below.
With the two competing options, one offered by Sony & Philips and the other by Toshiba, we seemed to be on the brink of yet another format war. It looked like a repeat of the format battle of the 1980s when the Sony Betamax was battling it out with the “Video Home System” VHS standards, at the expense of the consumer. What does the consumer buy? In my opinion the Betamax was a better option, but the consumer market decided, and the victory went to
But the impeding battle did not take place. Through the mediation of Lou Gerstner, president of IBM, a compromise was reached.
The Sony and Philips MMCD format was abandoned and the Toshiba SD format adopted, with these two additions:
the pit geometry which allows push-pull tracking, a proprietary technology of Philips and Sony, and the EFMPlus, created by Kees immink. The EFMPlus encoder is based on a deterministic finite state machine, having four states, which translates 8-bit input words into 16-bit codewords.
The DVD uses a red laser to scan the patterns of bumps on a mirrored surface, which are interpreted as bits. These bits can be assembled into bytes just as on a CD. However the bumps and tracks on a DVD are much smaller and can therefore hold significantly more information, up to 4.7GB.
This compromise created the DVD format, which became the standard format in December 1995 and will continue as such until the consumer market becomes dissatisfied with “standard video” and demands the high-density video format instead.
Professional Disc for Data (PDD)
With the decision made in favor of the Toshiba, Super Density Disc and the abandonment of the Multi Media Compact Disc (MMCD) as the main technology for the DVD, Sony set out to design a disc they called Professional Disc for Data (PDD). The need for a higher capacity disc for the upcoming high density television systems was a certainty.
Sony introduced the PDD in 2003 and it became available in 2004. This new format utilized the 405nm (Nana meter), blue-violet laser for reading and writing to the disc, allowing for a much higher data storage than the red laser used in the DVD. The capacity of the disc was 23GB compared with 4.5GB for a single layer DVD.
The PDD format was very short lived and was discontinued in 2007. This made way for the next generation of optical media for the Philips & Sony team, the Blu-ray.
HD DVD Developed by Toshiba
HD DVD has basically the same technologies as DVD, exempt it used a blue laser with a shorter wavelength and had therefore a higher capacity; Rom Single Layer 15GB, Rom Dual Layer 30GB The project was abandoned on February 19 2008
Blu-ray technology was developed jointly by Sony & Philips, along with an extensive board of directors.
Twentieth Century Fox
Blu-ray uses a 405nm wavelength blue-violet laser and has a tight track pitch of 0.85
The surface layer is 0.1mm-thick, which enables the laser to focus at the 0.85 aperture.
The disc uses a hard polymer coating called Durabis, which was developed by TDK and is supposedly? extremely resilient and fingerprint resistant.
The Java platform, which is used for menus and multimedia, is mandatory. Blu-ray systems must support JVM.
Blu-ray Disc Capacity
Rom Single Layer 25GB
Rom Dual Layer 50GB
RW Single Layer 27GB
RW Dual Layer 54GB
Highest Test 100GB
Theoretical Limit 200GB
On February 19, with the decision by Toshiba to abandon the HD-DVD, Blu-ray became the new standard and will prevail........until.........high-speed downloads of high-density videos?
Copyright Jacob Romeyn March 2008