Russell went on to invent the first system to record digital information on an optical transparent foil that was lit from behind by a high-power halogen lamp. Fact Who invented CDs? In his system laser read the minuscule pits binary patterns , and a computer converted the data into an electrical signal. Russell then found it a fairly simple tasks to convert the signal into an audible or visible transmission.
James Russell filed his first patent for an "Analog to digital to optical photographic recording and playback system" on September 1, and was granted patent number US on March 17, for his invention.
In a New York venture capitalist named Eli S. Jacobs became extremely interested in James Russell's ideas and established Digital Recording Corporation with the major objective of enhancing the product for the consumer video market.
Eli S. Jacobs appointed James Russell as Vice President to work on the invention of a a video disk. Russell went on to be granted over 20 patents for various elements of his compact disk system as he developed his ideas throughout the 's. There was no commercial interest in his ideas until the late 's when Philips and Sony began to develop ideas on laser and optical disc technology. Philips were convinced that an analog system was the only way ahead they were wrong!
Sony launched the first commercialized CD player in and early compact discs were made at just two factories, owned by Philips and Sony but were soon joined by other leading manufacturers in the music industry. Music CDs dominated the market despite the fact that they cost just about double the price of the equivalent vinyl record. Russell never received any money for his inventions because they were owned and controlled by his previous employers.
In , the CD-ROM entered the market and went beyond audio to record optical data storage and the photo CD was created by Kodak for the purpose of storing photographs in a digital format. CDs Who invented CDs? In Phillips and Sony developed the compact disc CD , an optical disc used to store and playback digital data.
It was originally developed to store and playback sound recordings exclusively. CDs can hold up to megabytes. This equates to up to 80 minutes of uncompressed audio. By billion CDs were sold worldwide.
It would take until after the Second World War before the LP became commercially available, even though it had been developed as long ago as the early s by RCA.
The shellac record continued to exist for some time next to the unbreakable LP, but it disappeared as soon as the 45 r. The mono Long Play record of the s and 60s had an extremely good sound quality, which was due partly to the advanced state that recording techniques had by then reached, as well as the constant improvements in the gramophones, which by then were called record players or turntables.
The stereo record was introduced in the mids. At first this was a disappointment, because the sound quality was noticeably poorer that that of comparable mono records. However the record industry was able to improve the quality of stereo records significantly within a few years, and even introduced 'quadraphonic' 4 channel stereo discs at the beginning of the s.
But quadraphonic sound was not successful. Not only were the techniques used at the limits of what was achievable at the time, but also the biggest problem was that in a short time four different and incompatible quadraphonic systems came onto the market at the same time! This meant that music enthusiasts had to buy four different decoders plus a new pick-up element with a specially shaped diamond needle to allow them to listen to the different quadraphonic records!
The digital era. Shortly after the demise of quadraphonic sound, the electronics industry moved into the digital era, and particularly optical recording. Following the pioneering work of Philips on an optical video player in the early 70's, a project was started in within Philips and its Research laboratories to develop a digital optical audio disk with error correction code. Parallel work on digital optical audio recording was done in a number of companies and Sony first publicly demonstrated an optical digital audio disc at the Audio Fair.
On 8 March , Philips demonstrated for the international press a The demonstration showed that it is possible by using digital optical recording and playback to reproduce audio signals with superb stereo quality. Through the co-operation with Sony the final diameter was 12 cm and the initially proposed resolution accuracy of 14 bits was increased to 16 bits.
With this concept Philips and Sony took the first step in setting a worldwide standard. In January of , the CD was awarded as the most valued Philips innovation, voted by readers of the Eindhovens Dagblad and listeners of Omroep Brabant, as well as by Philips Research employees.
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