Thanks to Hartmut Hackl for sending the pictures and specifications.
LaserVision format evolved from a collaboration with an earlier American system,
DiscoVision. The VLP-700 was the first LV player on sale in the UK , along with
the 600 which was basically the same but without a remote control facility. The
original intention was a UK launch in early 1980; this was put back to May 1981,
and then Autumn, as problems with the players and disc-pressing delayed the
release. Finally everything was ready and the VLP-700 and 600 were launched on
May 26 1982.
Laser scanning is a very sophisticated technique, particularly for the late seventies when this system was being developed. A laser beam is focused on the silver surface of a spinning disc, into which pits have been etched or pressed. The reflected beam is modulated by these pits, and this information is turned back into the video and sound signals. Since nothing actually touches the disc, laser systems are effectively free of wear and tear, and the beam can be freely moved around to produce all kinds of instant access and trick-play features. For example, rather than a film a single disc could be used to hold an entire library of over 50,000 separate colour stills on each side , all available within a second or two. These could be viewed for as long as the user wishes, without the head and tape wear which would be inevitable in the equivalent magnetic system.
Unlike modern digital CDs, which use a similar scanning technique, LV recordings are analogue - the pits vary in spacing, and hence frequency. For CAV discs, the disc spins at a fixed 1500rpm, and each frame takes up one revolution. This allows the machine to perform all kinds of tricks, such as still, reverse play, slow motion etc, as it always knows where the frames are. CLV discs, on the other hand, pack the frames as tightly as possible, so that while one frame takes up the whole of the inner part of the disc, at the outer edge three frames can be fitted in a single revolution. A CLV disc can therefore hold more frames, but must slow down as it plays From the centre out toward the edge. Since the frames can start anywhere the machine can't do all its tricks with a CLV disc, just a very basic jumping picture search. Unfortunately, there seem to be very few CAV discs in circulation, since almost all took advantage of the longer playing time of the CLV mode.
Internally, the machine has the usual Philips modular design, with rows of circuit boards each protected by its own tin-can shield. But the most striking thing about the player is the enormous helium-neon laser tube, with its plethora of danger and warning stickers. All modern laser devices (such as CD players) use tiny solid-state laser chips; the VLP-700 tube looks like something International Rescue would use to cut through a steel door!
Another interesting technical feature of LV is that the bandwidth is high enough to record a full chrominance signal, rather than the colour-under system used by all video tape systems. This gives purer colours and eliminates colour bleeding and cross-colour - the flickering "weatherman's tie" effect.
For this and other reasons, laser discs had the potential to leave tape standing in terms of picture quality, and LV was pushed as a high-quality format for buying and watching films. The original disc catalogue consisted of 120 titles, selling for £16 to £18 [1994: £27 to £31], and more were announced each month. But most shops seemed to ignore the format, few stocking more than a couple of discs - and the film companies themselves seemed reluctant to release titles on disc.
Philips desperately tried subsidising and then selling discs directly, then dropped the price of players - down to £299 [£480] by October 1983, including £50 worth of free discs. In March 1984 the price of players was £229 and discs were halved to £10, but even a national advertising campaign had little effect on sales. By 1986 the discs were still not selling even for a mere £5, and the format was essentially dead as a domestic product. The number of owners was estimated as "a few thousand".
LaserVision was re-launched for industry and schools, storing information and graphics with access controlled by a computer. One of the few well-known LV projects was the Domesday Disc, an archive of all the towns and villages in Britain, with maps, photographs, video clips and text for each one.