• Pranav Nandurkar

Do you know: Who invented Television?

It's hard to answer as it was the work of many individuals in the late 19th and early 20th centuries, with its roots initially starting from the back even in the 18th century. The idea of having something that transmits moving images existed long before the first television was built.  In the 1920s, over 50 inventors from Japan, Britain, Germany, America and Russia were all seriously attempting to build televisions, many of which had very promising demonstrations. First Mechanical television - Facsimile transmission systems pioneered methods of mechanically scanning graphics in the early 19th century. The Scottish inventor Alexander Bain introduced the facsimile machine between 1843 and 1846. The first practical facsimile system, working on telegraph lines, was developed and put into service by the Italian priest from 1856 onward. As a 23-year-old German university student, Paul Julius Gottlieb Nipkow proposed and patented the Nipkow disk in 1884. This was a spinning disk with a spiral pattern of holes in it, so each hole scanned a line of the image, although he never built a working model of the system. Constantin Perskyi had coined the word television in a paper read to the International Electricity Congress at the International World Fair in Paris on August 24, 1900.

By the 1920s, when amplification made television practical, Scottish inventor John Logie Baird employed the Nipkow disk in his prototype video systems.  He also started work on the first colour television. On March 25, 1925, Baird gave the first public demonstration of televised silhouette images in motion, at Selfridge's Department Store in London. Baird's system used the Nipkow disk for both scanning the image and displaying it. A brightly illuminated subject was placed in front of a spinning Nipkow disk set with lenses which swept images across a static photocell. The thallium sulphide (Thalofide) cell, developed by Theodore Case in the US, detected the light reflected from the subject and converted it into a proportional electrical signal. This was transmitted by AM radio waves to a receiver unit, where the video signal was applied to a neon light behind a second Nipkow disk rotating synchronized with the first. The brightness of the neon lamp was varied in proportion to the brightness of each spot on the image. As each hole in the disk passed by, one scan line of the image was reproduced. Baird's disk had 30 holes, producing an image with only 30 scan lines, just enough to recognize a human face. Further, many more inventors did their inventions in the coming period of time. The advancement of all-electronic television marked the beginning of the end for mechanical systems as the dominant form of television. Mechanical TV usually only produced small images. It was the main type of TV until the 1930s. The last mechanical television broadcasts ended in 1939 at stations run by a handful of public universities in the United States. First Electronic television -  In 1908 Alan Archibald Campbell-Swinton published a letter in the scientific journal Nature in which he described how "distant electric vision" could be achieved by using a cathode ray tube ( as both a transmitting and receiving device). The earliest version of the Cathode Ray Tube was invented by the German physicist Karl Ferdinand Braun in 1897 and is also known as the Braun tube. In 1937, two different teams, H. Miller and J. W. Strange, and H. Iams and A. Rose, succeeded in transmitting "very faint" images with the original Campbell-Swinton's selenium-coated plate. The problem of low sensitivity to light resulting in low electrical output from transmitting or "camera" tubes would be solved with the introduction of charge-storage technology by the Hungarian engineer Kálmán Tihanyi at the beginning of 1924. In 1926, Tihanyi designed a television system utilizing fully electronic scanning and display elements and employing the principle of "charge storage" within the scanning (or "camera") tube. The Russian Vladimir K. Zworykin applied for a patent for an electron scanning tube (a part that could be considered to be the “heart” of a television) in 1923 already, but could not get his television to work until 1934. Philo Taylor Farnsworth successfully demonstrated the first television signal transmission on September 7, 1927, with his scanning tube. A legal battle ensued in the late thirties, when RCA, the company Zworykin worked for wanted to claim the right to the patent (and the royalties). The court, however, ruled in favour of Farnsworth, giving him a patent priority and making him, officially the inventor of the first fully functional, all-electronic television. In 1978, James P Mitchell described, prototyped and demonstrated what was perhaps the earliest monochromatic flat panel LED television display LED Display targeted at replacing the CRT

First Colour television - The basic idea of using three monochrome images to produce a colour image had been experimented with almost as soon as black-and-white televisions had first been built. Older televisions have the RGB (Red-Green-Blue) colour scheme while modern televisions focus on LEDs to create the image. Among the earliest published proposals for television was one by Maurice Le Blanc in 1880 for a colour system, including the first mentions in television literature of line and frame scanning, although he gave no practical details. Polish inventor Jan Szczepanik patented a colour television system in 1897, using a selenium photoelectric cell at the transmitter and an electromagnet controlling an oscillating mirror and a moving prism at the receiver. But his system contained no means of analyzing the spectrum of colours at the transmitting end, and could not have worked as he described it. Another inventor, Hovannes Adamian, also experimented with colour television as early as 1907. The first colour television project is claimed by him and was patented in Germany on March 31, 1908, then in Britain, on April 1,  1908, in France and Russia in 1910.

One of the great technical challenges of introducing colour broadcast television was the desire to conserve bandwidth, potentially three times that of the existing black-and-white standards, and not use an excessive amount of radio spectrum. In the United States, after considerable research, the National Television Systems Committee approved an all-electronic Compatible colour system developed by RCA. Furthermore, due to advancement in technologies, we could see new generation televisions such as: -Smart television -3D television