Презентация на тему: " Topic «Television» MOBU «School 95. named. N. Shchukin» Prepared: Rusetskaya Tamara, a student 11klassa. Checked: Eugene P. Meshkova, an English teacher." — Транскрипт:
Topic «Television» MOBU «School 95. named. N. Shchukin» Prepared: Rusetskaya Tamara, a student 11klassa. Checked: Eugene P. Meshkova, an English teacher.
Development of television The rapid development of TV in the second half of the 20-th century has already grown for several generations, not of a life without TV. Broadcast quality has increased significantly and has become digital. The TVs have already ceased to be perceived as "boxes", which appeared flat LCD and plasma models. Screen sizes are measured by a pair of tens of centimeters. Television has become the norm.
Where it all began The influence of light on electricity for the first time (this is called the photoelectric effect-snatching electrons from a substance when exposed to light) discovered the German physicist Heinrich Hertz in He described their observations, but explain this phenomenon and failed. In February 1888, Russian scientist Alexander Stoletov experience clearly shows the influence of spent beam for electricity. Stoletovu was able to identify several patterns of this phenomenon. It was a prototype of the modern solar cells and so-called "electric eye". Later, similar research has many other great scientists including f. Lenard, j. Thompson, o. Richardson, c. Compton, r. Millikan, f. Ioffe, c. Lukirskij and c. Priležaev. But fully explain the nature of photoeffect was able only to Albert Einstein in 1905.
In parallel to these studies took place and many others who have played in a no less important role in the history of television. For example in 1879 by the English physicist William Kruksom substances which were opened when lights effects on them cathode rays – phosphors. Later it was found that the brightness of the glow phosphors directly depends on the strength of their exposure. In 1887, the first version of katodo-CRT (picture tube) is a German physicist Karl Brown.
In parallel to these studies took place and many others who have played in a no less important role in the history of television. For example, in 1879, f English By the end of 19-th century the idea of television doesn't seem to have something absurd and fantastic. None of the scientists have questioned the ability to transfer images over distances. One after the other, there are projects of television systems, for the most part, not feasible in terms of physics. The main principles of work television were created by the French scientist Maurice Leblanc. Independently, these works creates and American scientist e. Sawyer. They described the principle according to which image you want to quickly scan frame, with further turning it into an electrical signal. Since you know the radio then already existed and had been given to transfer of electric signals made by itself.
In 1907, Boris Rozingu was able to theoretically justify the possibility of obtaining images by electron-beam tubes, German physicist developed previously by k. Brown. Rozingu also managed to implement this in practice. And even managed to get a picture in the form of a single fixed point, this was a huge step forward. In General, the development of electronic television systems, Rosing has played an enormous role.
In 1933, United States, Russian immigrant Vladimir Zworykin demonstrated transferring electronic iconoscope-tube. It is generally considered that it is in. Zvorykin is the father of electronic television. Around the same time, regardless of the conveying tube Zvorykina creates and Soviet scientist n. Kataev.
Mechanical television sets. Nipkow Disk The first device for mechanical scanning has developed in 1884, German engineer Paul Gottlieb Nipkow. This device once again confirmed the justice statements about the simplicity of genius. His device was a rotating opaque disk with diameter up to 50 cm, with the spiral of Archimedes holes – the so-called nipkow disk (Nipkow disk device in the literature sometimes referred to as "electric telescope"). Thus was scanning the image light Ray, a signal to a special converter. To scan the same missing one (!) of the photoelectric cell. The number of holes, sometimes as many as 200 (usually from 30 to 100). Repeat the process on the television in reverse order-to produce an image again made of rotating disk with holes that was neon lamp. Using this simple system and was projected image.
In the same line by line, but with sufficient speed to the human eye have seen have a picture. Thus, the first to be created that is Projection TV. Image quality left much to be desired – only silhouettes, game of shadows, but nevertheless discern what show it was possible. Nipkow disk was the primary components of almost all mechanical systems, TVs, to their complete extinction as a species.
In 1925, the Swedish engineer John bird, was the first to achieve the transfer of recognizable human persons. Again, using a Nipkow disk. Later it was developed and first television system capable of transmitting moving images. First electronic TV suitable for practical use was developed in the American RCA research laboratory, led by Zvorykinym, at the end of the 1936 season. Later in the year 1939, RCA introduced the first TV set designed specifically for mass production.
This model was called the RCS TT-5. It was a massive wooden box equipped with a screen with a diagonal of 5 inches. First, the development of television was going in two directions – electronic and mechanical (sometimes referred to as a mechanical television "malostročnym TV"). With the development of mechanical systems were practically until the end of the 40-ies of the 20-th century, before it was completely supplanted by electronic devices. In the territory of the USSR, has beaten a little longer mechanical television systems.
We have Parallel to the development of television occurred on the territory of the Soviet Union. The first experimental broadcast took place on April 29, 1931 session of the year. From 1 October of the same year, TV shows have become regular. Because TVs still have not been carried out collective views, with designated areas. Many hams are beginning to assemble mechanical Soviet model TVs with their own hands (a bit more on this, see the article "Homemade TV").
In 1932, when developing a plan for the second five-year plan, the television was given a lot of attention. November 15, 1934 year broadcast television broadcast took place for the first time with sound. For quite a long time, there was only one channel is the first channel. At the time of the great patriotic war broadcast was interrupted and restored only after it ends. In 1960, a second channel. The first Soviet TV released industry called the b-2. This automatic model appeared in April, 32. First electronic TV was created much later-in the year This was the legendary KVN 49. TV was equipped with such a small screen, it's for more comfortable viewing in front of him was a special lens that needed to be filled with distilled water. In the future there and many other, more sophisticated models. However, build quality and reliability of Soviet TV (even the most recent models) were so low that became the talk of the town. Production of colour television sets, in the Soviet Union only started in mid 1967.
Color TV Although color television system has developed further in the year 1928, Zworykin only to 1950, it was possible its implementation. And then only as èksperementalnyh. Many years have passed since before this technology was available everywhere. First fit to sell colour television established in 1954, the same RCA. This model was equipped with a 15 inch screen. Later models were developed with 19 and 21 inch diagonals. Cost thousands of dollars more expensive systems United States and, therefore, not all were available. However, if desired, will be able to purchase this equipment in credit.
Due to difficulties with the widespread television color organization model color TV sets could not quickly displace the black and white, and for a long time, both types were produced in parallel. Single standard (PAL or SECAM) appeared and started vnedrâtsâ in 1967.
In the early radio lamps have been replaced by Semiconductor is the first TV based semiconductors was developed in 1960, the company Sony. Then came the chip-based model. Now there is a system in which all electronic filling TV is enclosed in a single chip. But talking about the history of television, one cannot but mention another relatively simple, but very important invention. The first remote control was established in the year This remote connect to my TV through a long wire. A few years later Robert Adler proposed the use of ultrasound for this purpose. There were also attempts to use the beam of visible light. But in the end settled on infrared, which is still in use.