Laserdisc Sizes
The most common size of Laserdisc was 11.81 in (30 cm). These approximated the size of 12 in (30 cm) LP vinyl records. These discs allowed for 30 minutes per side (CAV) or 60 minutes per side (CLV). The vast majority of programming for the Laserdisc format was produced on these discs.
A number of 7.9 in (20 cm) Laserdiscs were also published. These smaller "EP"-sized LDs allowed for 20 minutes per side (CLV). They are much rarer than the full-size LDs, especially in North America. These discs were often used for music video compilations (e.g. Bon Jovi′s "Breakout", Bananarama′s "Video Singles" or T'Pau's "View From A Bridge").
There were also 4.7 in (12 cm) "single"-style discs produced that were playable on Laserdisc players. These were referred to as CD Video (CD-V) discs, and Video Single Discs (VSD). A CD-V carried up to five minutes of analog Laserdisc-type video content (usually a music video), as well as up to 20 minutes of digital audio CD tracks. The original 1989 release of David Bowie's restrospective Sound and Vision CD box set prominently featured a CD-V video of Ashes To Ashes, and standalone promo CD-Vs featured the video, plus three audio tracks: John, I'm Only Dancing, Changes and The Supermen.
CD-Vs are not to be confused with Video CDs (which are all-digital and can only be played on VCD players, DVD players, CD-i players, computers, and later-model Laserdisc players, such as the DVL series from Pioneer that can also play DVDs). CD-Vs can only be played back on Laserdisc players with CD-V capability. VSDs were the same as CD-Vs, but without the audio CD tracks. CD-Vs were somewhat popular for a brief time worldwide, but soon faded from view. VSDs were popular only in Japan and other parts of Asia, and were never really introduced to the rest of the world.
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