Without falling into the trap of finding the original father of an invention, I would say every invention has multiple contributors i.e. just like having multiple fathers and sometimes multiple mothers too. So is the modern world television case, which with its debut forced us to rearrange our living areas into an entertainment cynosure.
Often J.L Baird is considered as the man behind televisions but the word television itself was coined many years ago by someone who was tele away from the original inventors. Prof. Constantin Perisky first coined the term Television in 1900 taking Tele (Far) from the Greek origin and Visio (sight) from the Latin origin, combining them into a new word that later largely magnified the broadcasting and entertainment industries.
Since then many scientists have worked parallelly as well as successively in the building of 20th-century television. Starting from the idea of photoconductivity to discovering the increased conductivity of Selenium when exposed to light by Willoughby Smith in 1873, the initial bits of television were building up steadily. The invention of the Nipkow spiral hole disk by P.J.G. Nipkow in 1884 became the driving wheel of mechanical televisions. With Nipkow's invention, the transmission of still imagery through the telegraph wire system became very easy for Henry Sutton. In 1885, he designed a device called Telephane which used Nipkows disk, selenium cells, Nicol prism, and Kerr cell. But the telegraph wires were not that efficient to transmit the then-going Melbourne cup successfully. Later the live transmission of images was effectively demonstrated in 1909 by Ernst Walter Ruhmer. This inspired another duo, George Rignoux, and A. Fournier to subsequently transmit live images using a similar kind of arrangement.
Parallelly, a new concept was being developed by Carl Ferdinand Braun. He invented the first Cathode ray tube inspired by the Crookes tube, which was previously inspired by the Geissler tubes, in the same year (1897) when J.J Thompson discovered the Electron. Braun was the first to use it as a display device. 1906 brought two more germans Max Deikman and Gustav Glaze to portray raster images for the 1st time in CRT. In 1907 a Russian Scientist named Boris Rosing used CRT to display simple geometrical shapes. Later in 1911 Rosing reused the CRT to display his subordinate Vladimir K. Zworkin's words "Very crude image" using a mechanical mirror type drum scanner. However, the selenium photoresistors used were inefficient to sense the changes of different intensities of light while trying to portray a moving image.
It remained undone unless a poor and dwindling scientific tinkerer with some household spares and parts bought from departmental store started building one of the world's first mechanical television. In 1923, Scottish Scientist John Logie Baird attempted the 1st trial to run a mechanical television using the same Nipkows Disk idea and he became successful. In 1925 he publically demonstrated moving silhouette images using a ventriloquist's dummy named "Stooky bill". Moving Stooky bill had high contrast paint on its face making it a suitable subject for proper detection. Baird's analog television system used a transmitter and a receiver. For both scanning in the transmitting end and displaying in receiving end, he used two giant Nipkows disks. The brightly illuminated dummy placed in front of the disk with a properly positioned set of lenses was used to scan the image across a static thallium sulfide photocell, which was transmitted through AM radio signals to the receiving unit. The receiving end had a second disc properly placed in front of a neon light. The light was varying in proportion to the brightness and contrast of each spot of the image. And due to the rotation, the spiral of 30 holes in his disc was producing 30 scanned lines, just enough to recognize the dummy. Later he did it with a human face. In the later phases of the 1920s, he also introduced the first transmission of moving images with tonal graduation, the first long distant TV signal transmission (705 km) using telephone lines, the first color transmission using 3 spiral discs with RYB color filters, & 3 light sources with the alternating commutator and the first transatlantic television transmission from London to Newyork.
In this period, he also became the first person to mass-produce television (receiver) also called televisor made by the electric company Plessy, England. A thousand pieces of these television receivers were produced and sold. These receivers used parts comprising of motors with synchronous gears assembly, set of lenses, lens box assembly with viewing tunnel, neon lamp with holder, discs (Nipkows), spindle assembly, control knobs, condenser, terminal board, resistance with brackets, and the casings. It was also sold in the form of a kit to be assembled by the consumer. [Refer Manual]
Many of his contemporaries tried their hands with similar kinds of technological advancements but were not as impactful as Baird's huge leaps until... [To be continued]
Summary:
In this blog, we have learned how different parts of the television were built by different personalities and it finally came to shape in a mechanical and later in an electromechanical form. The invention of photoconductive selenium cells, Nipkows disc, Nicols prism, Kerr cells, mirror type drum scanner, etc. eventually led to the invention of the mechanical television. In the next part of the blog, we will know how the fully electronic television was built using the CRT which became the revolution in the late 20th Century. Stay tuned!
References:-
1. http://www.earlytelevision.org/search.html
2. https://en.wikipedia.org/wiki/John_Logie_Baird
3. https://www.bairdtelevision.com/main.html
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