Video discs: the view from the 70s
The following were known to have had some interest in video discs, at least to the point of filing patent applications or telling the press they have something of interest. Unless specified, no details were ever made available.
Dayton, Ohio, USA
Response received in 1977: 'Arvin Systems no longer manufactures video disc systems. Please send further enquiries to Century Communications Corporation, 2260 Massaro Boulevard, Tampa East Industrial Park, Tampa, Florida 33619, USA.'
The Bosch Bildplatte was a high bandwidth (16 MHz) optical system using laser read-out of a disc spinning at 3,000 rpm. Track width was one micron. The recording master was made by laser etching on a metalised disc. Player head alignment was maintained by air pressure jets.
BTS System Entwicklung
BTS Discomat was an opto-electronic system. The last known tracking speed was 28mm/sec. and maximum playing time was quoted as up to 70 minutes per disc.
CBS Laboratories Division
New York, USA
By the time CBS Laboratories was acquired by Thomson-CSF in 1976 it seemed have have pulled out of the race, but still had an interest at least in software development.
Hitachi Electronics Company
Hitachi first declared its video disc interests in 1973 when it announced a system for recording up to 15 colour still pictures on a disc. At the end of 1975, Hitachi unveiled a moving picture disc system in which chrominance, luminance and sound information were encoded holographically.
Each frame was recorded as a 1mm diameter hologram on a 305mm disc, which rotated at only 6 rpm—thus indicating that freeze frame capacity would not be possible without a frame store. A laser beam read out the hologram from three angles. Capacity was 54,000 frames and running time is therefore 30 minutes for NTSC colour standard or 36 minutes for PAL and SECAM.
Munich, West Germany
A curiosity. A brief reference that the company had changed the name of its video disc system from Diskvision to Vid-Records, reportedly under pressure from MCA Disco-Vision. The only company with any similarity at all that could traced in any trade or telephone directory was Max Maschinenbau GmbH, 23 Kiel 17, Falconsteinerstrasse, West Germany—makers of diesel locomotives.
Matsushita Electric Industrial Company
Panasonic video disc.
Matsushita (Panasonic) demonstrated another mechanical disc system, Visc, in 1978. This crammed an hour of colour video on to each side of a 12 inch vinyl record. The disc span at 500 rpm, rather than 1500 rpm, which means that three frames would have been recorded per revolution. This means that proper freeze-frame would not have been possible - the best that could be achieved would be to repeat a single revolution—eg, three frames.
Visc was never launched, possibly due to the development by JVC, Matsushita's partner, of the more sophisticated SelectaVision/CED system described in a later exhibit.
Mitsubishi Electric Corporation
Magnetic video disc system was in development. However, it may have been intended as an 'action replay' device for professional use.
Oki Electric Industry
System for recording colour stills on video discs of 240mm or 152mm diameter.
Société d'Exploitation de Procédés Opto Electroniques (SORO)
Boulogne Billancourt, France
Optidisc was probably never demonstrated publicly. Its developers, SEPO, and intended distributor, SORO, remained silent and were difficult to contact. It was therefore regarded as an outsider and there was always some doubt about its ever reaching the glare of public scrutiny, let alone the marketplace.
Images were recorded by laser on standard 35mm film, providing separate tracks for chrominance and luminance, two audio channels, synchronisation and guidance. Information was transcribed via fibre optics in the form of short lines across the track at right angles to the direction of travel. The film was projected microscopically onto a photographically-coated glass 'mother' disc rotating at 2-6rpm.
Replication, at a rate of 50-100 discs a second, was done by photographic contact printing onto wide rolls of plastic-base film out of which the discs were subsequently punched. In the player, the signal is read out by light transmitted through the disc onto an array of photodiodes. In some respects, the system thus resembles that of i/o Metrics.
The prices quoted in 1974 were Ffr 1,000 (£110) for the player and Ffr 1 (1p) for disc production. Running time per disc was said to be one hour.
No connection with an optical disc replication company called Optidisc.
Bruce Somes-Charlton et al
Purley, Surrey, England
The British video disc system (exclusively reported in Screen Digest in 1973 and never heard of again). Laser read-out device guided by a stylus in a tracking groove. Somes-Charlton was involved in the early days of TeD at Decca and the work was carried out in British universities.
A video disc recorder, not dissimilar in principle to the Mavica video card, was described by Sony in late 1973. Identified only as a slow-motion magnetic sheet video recorder, the system recorded monochrome images of up to 10 seconds' duration on a thin circular polyester sheet of 280mm diameter with a magnetic oxide coating.
The disc was inserted from beneath; this curious arrangement was because an air cushion was formed by the spinning disc which was relied on for closer head/disc contact. The disc and/or head could be damaged when the disc started up or slowed down if the head is resting on the disc while in direct contact with the support plate. Track life was claimed to exceed 1,000 hrs without deterioration.
Applications of the system were envisaged as being for such short duration events as medical X-ray recording at stepped speeds (15 per second to one every two seconds) and in Sony's Sports Clinic System for analysis of golf swings, etc. Recording of independent frames was also possible: Japan National Railways tried out the system for logging and monitoring of locomotive stock movements. Other motion analysis applications were envisaged but no entertainment or domestic uses.
Polygramovision. Reports indicated an electro-mechanical system using a double stylus and operating at 45rpm and 33rpm with playing times of 3 minutes and 25 minutes respectively. The players also reproduced standard audio discs.
Syndor Barent Scanner Corporation
New Mexico, USA
Chromadisc remained something of a mystery. Syndor Barent, described as 'a small research foundation', never specifically indicated what it had to offer. Early reports (see Screen Digest 1972) were of a 305mm disc dotted with a spiral pattern of 1mm microlenses, each of which contained a full image. Optical scanning was used for read-out and playing time was quoted as 45 minutes colour or 90 minutes monochrome. Speed was given as 0.5 rpm.
Reference was made—only occasionally—to 'videoplayers', such as in the Business Screen article in which Nels Winkless III of Syndor-Barent referred to 'a method of recording 45 minute sound, colour movies on l2-inch discs of plastic on $150 videoplayers'. (The article was sent to us by Mr Winkless 'for its entertainment value'. He also commented on SB's 'quiet technical progress and cheerful poverty'.)
University of Toronto Institute of Aerospace Studies
Plastic discs were recorded by deformation of the surface by a laser for immediate playback or replication. The player used low-cost materials and a low power laser; discs play 60 minutes and are 305mm diameter.
Xerox Electro-Optical Systems
Pasadena, California, USA
A five-year research project involving a staff of 25 was under way—some of the staff came from Zenith—and it was believed that the optical disc standard would be adopted.
Zenith Radio Corporation
The quest for home video
Chicago, Illinois, USA
At the time of the Video Disc 76 conference, Screen Digest noted that 'Zenith can claim to have left more room for speculation about their video disc intentions than any other company'. Eighteen months later, Zenith appeared to have withdrawn from video disc research and development unequivocally.
In spring 1976 the company stated: 'Our investigations of video disc players are for technical evaluation purposes only. At this stage we have not endorsed any system nor have we initiated any commercial development of a specific system of our own.' It was known that interest had centred on optical systems and in particular the Philips/MCA system. Zenith's participation in evolving the specifications was publicly announced but not signalled in the document.
The decision to abort the project came as the first recording was about to be made—but not for the newly revived thicker disc adopted by Philips/MCA and Thomson.