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: For the punk-rock band, see Television (band) , 1958 .]] Television is a Telecommunication System for Broadcasting and receiving Moving Picture s and Sound over a Distance . The Term has come to Refer to all the Aspect s of television Programming and Transmission as well. The word is derived from mixed Latin and Greek roots, meaning "far seeing" (Greek "tele," meaning far, and Latin "visus," meaning seeing). ORIGINS The origins of what would become today's television system are traced back as far as the scanning disk of Paul Nipkow of 1885. All practical television systems use the fundamental idea of scanning an image to produce a time series signal representation. That representation is then transmitted to a device to reverse the scanning process. The final device, the television, relies on the human eye to integrate the result into a coherent image again. While electromechanical techniques were developed prior to World War II, most notably by John Logie Baird , all-electronic television systems relied on the inventions of Philo Taylor Farnsworth , Vladimir Zworykin and others to produce a system suitable for mass distribution of television programming. Commercial broadcast programming, following years of experimental broadcasts seen only in a few specially-equipped homes, occurred in both the United States and the United Kingdom before World War II. The first television broadcasts with a modern level of definition (240+ lines) were made in England in 1936. Television did not become commonplace in United States homes until the middle 1950s. While North American over-the-air broadcasting was originally free of direct marginal cost to the consumer (i.e., cost in excess of acquisition and upkeep of the hardware) and broadcasters were compensated primarily by receipt of advertising revenue, increasingly television consumers obtain their programming by subscription to cable television systems or direct-to-home satellite transmissions. In the United Kingdom, on the other hand, the owner of each television must pay a licence fee annually which is used to support the British Broadcasting Corporation . TECHNOLOGY Elements of a television system The elements of a simple television system are:
Practical television systems include equipment for selecting different image sources, mixing images from several sources at once, insertion of pre-recorded video signals, synchronizing signals from many sources, and direct image generation by computer for such purposes as station identification. Transmission may be over the air from land-based transmitters, over metallic or optical cables, or by radio from synchronous Satellite s. Digital systems may be inserted anywhere in the chain to provide better image transmission quality, reduction in transmission Bandwidth , special effects, or security of transmission from theft by non-subscribers. Display technology Thanks to advances in display technology, there are now several kinds of video displays used in modern TV sets:
See Also: Liquid crystal display television Signal connections The number of ways to connect a video device to a television has increased over the years:
Aspect ratios "Aspect ratio" refers to the ratio of the vertical to horizontal measurements of a television's picture. Mechanically scanned television as first demonstrated by , oriented for the head and shoulders of a single person in close-up. Most of the early electronic TV systems from the mid-1930s onward shared the same used in cinema films at the time. This ratio was also square enough to be conveniently viewed on round Cathode-ray Tube s (CRTs), which were all that could be produced given the Manufacturing Technology of the time. (Today's CRT technology allows the manufacture of much wider tubes, and the Flat Screen technologies which are becoming steadily more popular have no aspect ratio limitations at all.) The BBC's television service used a more squarish 5:4 ratio from 1936 to 3 April 1950 , when it too switched to a 4:3 ratio. In the 1950s, Movie Studio s moved towards Widescreen aspect ratios such as Cinerama in an effort to distance their product from television. Although this was initially just a Gimmick , widescreen is still the format of choice today and square aspect ratio movies are rare. Some people argue that widescreen is actually a disadvantage when showing objects that are tall instead of Panoramic , others say that natural vision is more panoramic than tall, and therefore widescreen is easier on the eye. The switch to s; the ATSC HDTV system uses straight widescreen format, no image squashing or expanding is used. Recently "widescreen" has spread from television to computing where both s, as opposed to viewing content full-screen. =Aspect ratio incompatibility The television industry changing aspect ratios is not without teething difficulties, and can present a considerable problem. Displaying a widescreen aspect (rectangular) image on a conventional aspect (square) display can be shown:
A conventional aspect (square) image on a widescreen aspect (rectangular) display can be shown:
A common compromise is to shoot or create material at an aspect ratio of 14:9, and to lose some image at each side for 4:3 presentation, and some image at top and bottom for 16:9 presentation. Horizontal expansion has advantages in situations in which several people are watching the same set, as it compensates for watching at an oblique angle. Sound Television add-ons Today there are many add-ons for the television set. A few add-ons include Video Game Consoles, VCR s, Cable Boxes, Satellite Boxes, DVD players, or Digital Video Recorders (including personal video recorders, PVRs), the television add-on market is ever growing. Many such devices which are used for program reception, are known generically as Set Top Boxes. New developments
GEOGRAPHICAL USAGE See Also: Geographical usage of television CONTENT Advertising Since their inception in the USA in 1941, TV Commercial s have become one of the most effective, most pervasive, and most popular methods of selling products of many sorts, especially consumer goods. U.S. advertising rates are determined primarily by Nielsen Ratings . Programming Getting TV programming shown to the public can happen in many different ways. After production the next step is to market and deliver the product to whatever markets are open to using it. This typically happens on two levels: #Original Run or '''First Run''' - a producer creates a program of one or multiple episodes and shows it on a station or network which has either paid for the production itself or to which a license has been granted by the producers to do the same. # Syndication - this is the terminology rather broadly used to describe secondary programming usages (beyond original run). It includes secondary runs in the country of first issue, but also international usage which may or may not be managed by the originating producer. In many cases other companies, TV Stations or individuals are engaged to do the syndication work, in other words to sell the product into the markets they are allowed to sell into by contract from the copyright holders, in most cases the producers. In most countries, the first wave occurs primarily on Free-to-air (FTA) television, while the second wave happens on subscription TV and in other countries. In the U.S. however, the first wave occurs on the FTA networks and subscription services, and the second wave travels via all means of distribution. First run programming is increasing on subscription services outside the U.S., but few domestically produced programs are syndicated on domestic FTA elsewhere. This practice is increasing however, generally on digital only FTA channels, or with subscriber-only first run material appearing on FTA. Unlike the U.S., repeat FTA screenings of a FTA network program almost only occur only on that network. Also, affiliates rarely buy or produce non-network programming that isn't intensely local. SOCIAL ASPECTS Alleged dangers Paralleling television's growing primacy in family life and society, an increasingly vocal chorus of legislators, s of television per week and features studies showing it interferes with the Education al and maturational process. A , a finding backed up by reports of withdrawal symptoms among families forced by circumstance to cease watching. A longitudinal study in New Zealand involving 1000 people (from childhood to 26 years of age) demonstrated that "television viewing in childhood and adolescence is associated with poor educational achievement by 26 years of age". In other words, the more the child watched television, the less likely he or she was to finish school and enroll in a University . In Iceland , television broadcasting hours were restricted until 1984, with no television programs being broadcast on Thursday, or during the whole of July. Technology trends In its infancy, television was an ephemeral medium. Fans of regular shows planned their Schedules so that they could be available to watch their shows at their time of broadcast. The term ''appointment television'' was coined by marketers to describe this kind of attachment. The viewership's dependence on schedule lessened with the invention of programmable video recorders, such as the Videocassette Recorder and the Digital Video Recorder . Consumers could watch programs on their own schedule once they were broadcast and recorded. Television service providers also offer ''video on demand,'' a set of programs which could be watched at any time. Both Mobile Phone networks and the Internet are capable of carrying video streams. There is already a fair amount of internet TV, while mobile phone TV is planned to become mainstream, if it can be effectively sold, early in 2006. Suitability for audience Almost since the medium's inception there have been charges that some programming is, in one way or another, inappropriate, Offensive or Indecent . FURTHER READING
REFERENCES David E. Fisher and Marshall J. Fisher, ''Tube, the Invention of Television'', Counterpoint, Washington D.C. USA, (1996) ISBN 1887178171 SEE ALSO
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