The film was released on VHS, Laserdisc, CED videodisc, and DVD. A keel-shaped diamond stylus appeared as a byproduct of the invention of the CED Videodisc. It was subsequently released on VHS and CED Videodisc. The film was later released for sale in VHS, CED Videodisc, Laserdisc, and DVD formats. A Laserdisc from MCA Videodisc was released the same year. The context was RCA's write-off of $100M's of investment in capacitive-pickup videodisc technology. Over the years, the film has been released on VHS, LaserDisc, SelectaVision videodisc, and DVD. Home video collections were also released on the VHS, Beta, CED Videodisc, and Laserdisc formats. In 1981, responsibility for the laser videodisc was sold to Pioneer Electronic Corporation. "Tron" was originally released on VHS, Betamax, LaserDisc, and CED Videodisc in 1983. The film appeared on videotape and videodisc in April 1985. The film was first released in 1983 on VHS and CED Videodisc. A catalog of approximately 50 videodisc titles was released at the same time. The analogue videodisc developed by NV Philips was the pioneering technology for interactive media. Thomson exited the videodisc market in 1981.