is a general term for a laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...
- or stylus
A stylus is a writing utensil, or a small tool for some other form of marking or shaping, for example in pottery. The word is also used for a computer accessory . It usually refers to a narrow elongated staff, similar to a modern ballpoint pen. Many styli are heavily curved to be held more easily...
-readable random-access circular disc that contains both audio
Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.-Propagation of...
and analog video
Analog video is a video signal transferred by an analog signal. An analog color video signal contains luminance, brightness and chrominance of an analog television image...
signals recorded in an analog form. Typically, it is a reference to any such media that predates the mainstream popularity of the DVD
A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....
E & H T Anthony a camera maker based in New York marketed in 1898 a combination motion picture camera and project called "The Spiral" that could capture 200 images arranged in a spiral on an 8 inch diameter glass plate, which when played back at 16 frames per second would give a running time of 13 seconds.
Theodore Brown patented in 1907 (UK patent GB190714493) a photographic disk system of recording approximately 1,200 images in a spiral of pictures on a 10 inch disk. Played back at 16 frames per second, the disk could provide around one and a quarter minutes of material. The system was marketed as the Urban Spirograph by Charles Urban
Charles Urban was an Anglo-American film producer and distributor, and one of the most significant figures in British cinema before the First World War...
, and discs were produced - but it soon disappeared
John Logie Baird
John Logie Baird FRSE was a Scottish engineer and inventor of the world's first practical, publicly demonstrated television system, and also the world's first fully electronic colour television tube...
, created the Phonovision
Phonovision is a proof of concept format and experiment for recording a mechanical television signal on phonograph records. The format was developed in the late 1920s in London by Scottish television pioneer John Logie Baird...
system in the early 1930s, which mechanically produced about four frames per second. The system was not successful.
P.M.G Toulon, a French inventor working at Westinghouse Electric during the 1950s and 1960s patented a system in 1952 (US Patent 3198880) which used a slow spinning disc with a spiral track of photographically 1.5 millimeter wide recorded frames, along with a flying spot scanner, which swept over them to produce a video image. This was intended to be synchronously combined with playback from a vinyl record. It appears a working system was never produced. The has similarities with the tape based Electronic Video Recording
Electronic Video Recording, or EVR, was a film-based video recording format developed by Hungarian-born engineer Peter Carl Goldmark at CBS Laboratories in the 1960s....
system, which was released for professional use.
Westinghouse Electric Corporation developed a system in 1965 called Phonovid, that allowed for the playback of 400 stored still images, along with 40 minutes of sound. The system used a standard record player, and built the picture up slowly.
The Television Electronic Disc
Television Electronic Disc is a discontinued video recording format, released in 1975 by Telefunken and Teldec. The format used flexible foil discs, which spun at 1,500 rpm on a cushion of air...
, a mechanical system was rolled out in German and Austria in 1970 by Telefunken. 12 inch discs had a capacity of about eight minutes however it was abandoned in favor of VHS
The Video Home System is a consumer-level analog recording videocassette standard developed by Victor Company of Japan ....
by its parent company.
Visc was a mechanical video disc system developed by Matsushita (later Panasonic
Panasonic is an international brand name for Japanese electric products manufacturer Panasonic Corporation, which was formerly known as Matsushita Electric Industrial Co., Ltd...
, the 12 inch vinyl disc was spun at 500 rpm with each revolution holding three frames of color video. With a total of up to an hour of video on each side of the disc. Discs could be recorded in either a 30 minutes per side format, or a 60 minutes per side format. A later incarnation of the system used 9 inch discs in caddies capable of storing 75 minutes per side The system was abandoned in January 1980 in favour of JVC's VHD system.
MCA, Inc. was an American talent agency. Initially starting in the music business, they would next become a dominant force in the film business, and later expanded into the television business...
Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....
DiscoVision is the name of several things related to the video laserdisc format. It was the original name of the "Reflective Optical Videodisc System" format later known as LaserVision or LaserDisc....
system was released in 1978, an optical reflective system read by a laser beam. It was renamed several times, as Laservision
, CD Video
, but is probably best known as Laserdisc
LaserDisc was a home video format and the first commercial optical disc storage medium. Initially licensed, sold, and marketed as MCA DiscoVision in North America in 1978, the technology was previously referred to interally as Optical Videodisc System, Reflective Optical Videodisc, Laser Optical...
Thomson CSF created a system that used thin flexible video discs, which used a transmissive laser system, with light source and pickup on opposite sides of the disc. The system was marketed for Industrial and Educational use in 1980. Each side of the disc could hold 50,000 still CAV frames, and both sides could be read without removing the disc. Thomson exited the videodisc market in 1981.
RCA Corporation, founded as the Radio Corporation of America, was an American electronics company in existence from 1919 to 1986. The RCA trademark is currently owned by the French conglomerate Technicolor SA through RCA Trademark Management S.A., a company owned by Technicolor...
produced a system called CED under the brand SelectaVision
The Capacitance Electronic Disc was an analog video video disc playback system developed by RCA, in which video and audio could be played back on a TV set using a special needle and high-density groove system similar to phonograph records....
in 1981. The system used a physical pickup riding in grooves of a pressed disc, reading variance in capacitance in the underlying disc. The system competed with Laserdisc for a few years, before being abandoned.
, usually referred to as JVC, is a Japanese international consumer and professional electronics corporation based in Yokohama, Japan which was founded in 1927...
produced a system very similar to CED called Video High Density, it was launched in 1983 and marketed predominantly in Japan.
Laserfilm was a videodisc format developed by McDonnell-Douglas in 1984 that was a transmissive laser-based playback medium . It worked by having the laser to shine through one side of the disc to a receiving sensor on the other side, where the beam of the laser would be interrupted by a spiral of...
, a videodisc format developed by McDonnell Douglas
McDonnell Douglas was a major American aerospace manufacturer and defense contractor, producing a number of famous commercial and military aircraft. It formed from a merger of McDonnell Aircraft and Douglas Aircraft in 1967. McDonnell Douglas was based at Lambert-St. Louis International Airport...
MovieCD was a format for digital video storage and consumer home video playback during the mid to late-1990s, marketed by SIRIUS Publishing, Inc., and was rendered obsolete by the wider distribution of DVD...
, by SIRIUS Publishing, Inc. (1995?)
Video discs can be classed based on their playback mechanism:
- Capacitance Based
- Optical discs
- Laserdisc, CD, DVD, Bluray, etc.
- Thomson CSF system
- Multiple sub-Nyquist sampling encoding (MUSE) an early high-definition video
High-definition video or HD video refers to any video system of higher resolution than standard-definition video, and most commonly involves display resolutions of 1,280×720 pixels or 1,920×1,080 pixels...