Compact disc


August 19, 2022

The Compact disc (lit. "compact disk"; abbreviated to CD or cd), also Italianized with little luck with the name "compact", is a standardized type of optical disc used in various fields for storing information in digital format , which for the first time in history has made it possible to overcome the insuperable limit of any previous analog support, that is the progressive wear of the vinyl record as it was used, due to the physical consumption of the record caused by the repeated passages of the stylus of the record player.


Its genesis is due to the research, by the world of telephony, of an efficient system for multiplying information, through the digitization and simplification of signals. The joint application of the binary numerical system and the laser to sound gave birth to the compact disc. In the early years, the project was initially followed by a joint venture between DuPont and Philips. DuPont could boast an enormous experience in polycarbonate (invented in 1928 by DuPont itself) and a strong presence in the Netherlands with a chemical installation in Dordrecht, near Rotterdam. DuPont also already had a joint venture with Philips, the ill-fated PDM (Philips-DuPont Magnetics, also sponsor of the PDM-Concorde cycling team), to develop magnetic tapes using two other DuPont products: the Cronar polyester backing (DuPont invention of 1955 ) and Crolyn chromium oxide (DuPont invention of 1956). DuPont also had another joint venture with British Telecom (BT&D) to develop microlaser and fiber optics. There were therefore all the conditions for excellent developments. After the first prototypes, the European management met in Geneva to analyze the development of the project and the necessary investments. These investments also included a possible factory in Italy, to use Ilva's aluminum. Preliminary studies revealed that the development of the CD would allow the creation of a disc with a capacity of over 600MB of data and probably over an hour of music in digital format. This did not thrill DuPont managers due to the huge investments required: taking into account that personal computers of the time had memories from 64 KB to 4 MB and hard drives of 20 MB, the capacity of the new medium would have been exaggerated in comparison to the real needs. of the time. Even for music it was unthinkable that the whole world would replace turntables and recorders with the new, very expensive optical disc players (and in fact this did not happen on a mass level until the 1980s). DuPont management rejected the project and therefore asked Philips to continue on its own, thus forcing the company to seek other alliances for the development of support. For a few years, however, the PDO (Philips-DuPont Opticals) remained alive, printing CDs with production in the UK (mainly music) and USA (data). The PDO closed in 1990 due to "differences of interest". It can therefore be said that the true authorship of the CD is to be attributed to Philips and DuPont, even if DuPont did not participate in any subsequent development and completely exited the project at the initial stage. In fact, the design of the CD in its final configuration dates back to 1979, and is due to a new joint venture between Philips and the Japanese company Sony, which since 1975 was experimenting independently with the technology for a digital optical disc. On August 17, 1982, the first CD for commercial use was produced in a Philips factory in Hanover in Germany: Richard Strauss's Symphony of the Alps conducted by Herbert von Karajan with the Berliner Philharmoniker. The first pop album to be printed on the new medium was The Visitors of the Swedish group ABBA, but the first to be released was Billy Joel's 52nd Street, released on October 1, 1982 in Japan ins