Recordable Formats
Another type of video media, CRVdisc, or "Component Recordable Video Disc" were available for a short time, mostly to professionals. Developed by Sony, CRVdiscs resemble early PC CD-ROM caddies with a disc inside resembling a full-sized LD. CRVdiscs were blank, write-once, read-many media that could be recorded once on each side. CRVdiscs were used largely for backup storage in professional/commercial applications.
Another form of recordable Laserdisc that was completely playback-compatible with the Laserdisc format (unlike CRVdisc with its caddy enclosure) is the RLV, or Recordable LaserVision disc. It was developed and first marketed by the Optical Disc Corporation (ODC, now ODC Nimbus) in 1984. RLV discs, like CRVdisc, are also a WORM technology, and function exactly like a CD-R disc. RLV discs looked almost exactly like standard Laserdiscs, and could play in any standard Laserdisc player after they have been recorded.
The only cosmetic difference between an RLV disc and a regular factory-pressed Laserdiscs was their reflective purple-violet (or blue with some RLV discs) color resulting from the dye embedded in the reflective layer of the disc to make it recordable, as opposed to the silver mirror appearance of regular LDs. The purplish color of RLVs was very similar to present-day DVD-R and DVD+R discs. RLVs were popular for making short-run quantities of Laserdiscs for specialized applications such as interactive kiosks and flight simulators.
In spite of nonrecordability being commonly regarded as the primary weakness of the Laserdisc format, these recordable LD systems were never marketed toward the general public, and are so poorly known as to create the misconception that a home recording system for Laserdiscs was impossible.
Read more about this topic: Laserdisc