Profile of James Russell on Famous Like Me

James Russell (born 1931 in Bremerton, Washington) is an American inventor. He earned a BA in physics from Reed College in Portland in 1953. He joined General Electric's nearby labs in Richland, Washington, where he initiated many types of experimental instrumentation. He also designed the first electron beam welder and built it. In 1965, Russell joined the Pacific Northwest Laboratory of Battelle Memorial Institute in Richland, where he introduced his ideas and theories about optical data storage, constructing prototypes of digital to optical recording systems. He did pioneering work of digital optical recording and playback now used for CDs and DVDs. His work has been done in isolation, and did not affect the independent work accomplished by pioneering research within MCA, Thomson, and Philips that forms the basis of the CD and its successors.

Physical details of the early Russell patents

The three earliest patents by Russell, US 3,501,586, 3,642,284, and 3,795,902 were filed in 1966, 1967, and 1969 respectively. Early analog optical recording technology, which forms the physical basis of Laserdisc, CD and DVD technology, was first published/filed by Gregg in 1958 and Philips researchers, Kramer and Compaan, in 1969.

Major features of the early Russell patents are:

• The preferred embodiment of the scanning mechanism is awkward since the disc is not rotating but fixed. A scanning mirror with which the light is deflected is attached to a rotating shaft.
• The entire disc or oblong sheet to be read is illuminated by a large playback light source at the back of the transparent plate instead by focused laser light in reflective mode. There is no objective lens for reading the data.
• Dynamic track or focus servos are absent.
• The patent specification mentions the use of a protective layer(s) or coating to prevent scratching during handling, but the layer does not offer significant benefits, as its task is merely to protect. Fingerprints and scratches will obscure the data read. In a CD, on the other hand, where a focused laser beam is used in conjunction with a protective layer at the reading side of the disc, scratches and fingerprints are out of focus, and thus not detected by the reading spot. As a result, the CD/DVD method offers a great resilience against disc anomalies, offering great playability.
• According to the patent specifications the spot diameter is around 10 micrometres. Thus, the areal information density is, according to the patent specifications, around a factor hundred less than that of a regular CD, which means a capacity of 5 Mbytes for a disc of 12 cm diameter. The inevitable downside to this is that Russell’s disc offers playing time less than one minute of digital CD sound or, alternatively, less than a second of digital video. When the disc is scanned at 30 Mbit/s, as claimed above, Russell’s disc would be read in less than two seconds. This would set an absolute record in current CD-ROM practice, where it takes minutes to do so. It actually means a factor1800X CD-ROM drive. It is not clear from the patents how this huge X-factor could be accomplished mechanically.
• Photographically copying of data.
• The patents do not address details of the digital techniques used and/or details of methods how to solve the problems associated with extremely high bit rates of digital video signals. Due to limitations of electronics circuitry, there was no (MPEG) source coding at the time to lower the overall bit rates. The uncompressed bit rate of a color video signal is around 200 Mbit/s, and it is far from clear how the mechanical (scanning speed) and electronic challenges imposed by these enormous bit rates were solved. The patents do not mention error correction or other digital coding technology.

US 3,941,927, filed 1974, advocates the use of an optical fiber deflection device for scanning a photo with a digital image. Russell’s younger patents were filed after 1975 when Sony, Philips and other companies started digital optical recording using laserdisc recording technology.

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