CD player in 1970. Following litigation, Sony and Philips licensed Russell's patents (then held by a Canadian company, Optical Recording Corp.) in the 1980s. The Compact Disc is an evolution of LaserDisc technology, where a focused laser beam is used that enables the high information density required for high-quality digital audio signals. Prototypes were developed by Philips and Sony independently in the late 1970s. In 1979, Sony and Philips set up a joint task force of engineers to design a new digital audio disc. After a year of experimentation and discussion, the "Red Book" CD-DA standard was published in 1980. After their
Philips CD-i partnered in 1992 with Amsterdam-based CDMATICS to develop TeleCD-i (also TeleCD). In this concept, the CD-i player is connected to a network such as PSTN or Internet, enabling data-communication and rich media presentation. Dutch grocery chain Albert Heijn and mail-order company were early adopters and introduced award-winning TeleCD-i applications for their home-shopping and home-delivery services. CDMATICS also developed the special Philips TeleCD-i Assistant and a set of software tools to help the worldwide multimedia industry to develop and implement TeleCD-i. TeleCD-i is the world's first networked multimedia application at the time of its introduction. In 1996, Philips acquired source code