Industrializaçao e impacto ambiental

Appearance and Evolution of TV

The advent of television is the major mathematicians and physicists, belonging to the sciences that delivered to the Humanities are a large and powerful vehicle. Since the early 19th century, scientists were worried about image transmission distance and were with the invention of Alexander Bain in 1842, who obtained the telegraphic transmission of an image (facsimile), currently known as fax.

In 1817, the Swedish chemist Jons Jakob Berzelius, discovered the selenium, but only 56 years later, in 1873, Willoughby Smith that English has proven that selenium possessed the property transform light energy into electrical energy. Through this discovery can be developed to transmit images via the mains.

In 1884, the young German Paul Gottlieb Nipkow invented a disk with holes spiral with the same distance between themselves that would cause the object subdividisse in small elements that together form an image.

In 1892, Julius Elster and Hans Getiel invented the photocell electric signal. They turned each subdivision in 1906, Arbwehnelt developed a system of television by cathode rays, and the same would occur in Russia by Boris Rosing. The system employed a mechanical mirror operation coupled to the cathode.
In 1920, the real English broadcasts, thanks to John Logie Baird's mechanical system based on the invention of the Nipkow disk. Four years later, in 1924, Baird transmitted the contours of objects at a distance and in the following year, physiognomies people. Already in 1926, Baird gave the first demonstration at the Royal Institution in London for the scientific community and soon after signed a contract with the BBC for experimental transmissions. The standard definition had 30 lines and mechanical era.

During this period, in 1923, the Russian Wladimir Zworykin discovered iconoscope, invention that used cathode ray tube. In 1927, Philo Farnsworth discovered a Prosector of images by cathode rays, but with no satisfactory