28-12-2023, 03:41 PM
And fairy tales etc had scrying (distance viewing) in bowls of water and mirrors maybe from 10th C. Crystal balls are a later idea.
So people wanted to develop the technology because they had the idea. The Camera Obscura idea is very old and may have been used by some of the "Old Master" painters, though earlier was in China. Still photos needed the discovery of Nitric Acid (to make photo sensitive silver nitrate) which dates from 13th C, but electric batteries were discovered/invented by Volta in 1799, first still photographs in 1822, electrical telegraph 1830s (Morse type systems 1848-1865) though there was earlier optical telegraph. Cold cathode CRT in 1897, hot cathode in 1922 (but could have been done earlier).
Marconi Wireless was used during the Boer War, and could have been used with Nipkow's mechanical TV. But by 1905 it was realised that Wireless Remote viewing (Television) needed an electronic camera. Farnsworth's was a dead end because no per frame storage/integration.
In 1911, Boris Rosing and his student Vladimir Zworykin created a system that used a mechanical mirror-drum scanner to transmit, in Zworykin's words, "very crude images" over wires to the "Braun tube" (CRT). Later some Dutch people used CRTs with the mechanical "Baird" system, before Baird used a CRT. Radio Fax was also used after hours in the USA on MW. Wired fax was first demonstrated about 1851. About 1909 saw a matrix of selenium cells used as a very low resolution camera. Colour transmissions on mechanical TV were in Germany about 1924.
Zworykin's big breakthrough was that each part of the camera target integrated over the entire frame interval, not just at the instant of reading (Farnsworth).
Electricity and photography gave inventors and scientists the impetus to pursue the technological realisation of "seeing at a distance" in old fairy tales.
Long distance "ẅriting at a distance" preceded electricity with Chappe in 1792. By the time of the Napoleonic War the networks stretched thousand of miles in Europe. Fictionalised in Terry Prachett's Discworld as the Clacks.
So the ingredients of TV were:
1799: Batteries and start of Electrical Age.
Movie film (a big spur) in late 1890s as development from photography in 1822.
1897 CRT
Marconi commercialising Maxwell & Hertz for radio in 1890s
Hot cathode CRT 1922
Maxwell on need only for R G B (mid 1800s) for Colour TV.
Amplifying valves (Edison, DeForest, Fleming etc)
Zworykin's camera tube was the final bit of the puzzle. The 1951 Colour was inevitable.
By the 1970s there was experimentation with Digital TV encoding and lasers on fibre optics for communication.
Semiconductor research predates valves. 1948 simply needed pure enough materials!
So people wanted to develop the technology because they had the idea. The Camera Obscura idea is very old and may have been used by some of the "Old Master" painters, though earlier was in China. Still photos needed the discovery of Nitric Acid (to make photo sensitive silver nitrate) which dates from 13th C, but electric batteries were discovered/invented by Volta in 1799, first still photographs in 1822, electrical telegraph 1830s (Morse type systems 1848-1865) though there was earlier optical telegraph. Cold cathode CRT in 1897, hot cathode in 1922 (but could have been done earlier).
Marconi Wireless was used during the Boer War, and could have been used with Nipkow's mechanical TV. But by 1905 it was realised that Wireless Remote viewing (Television) needed an electronic camera. Farnsworth's was a dead end because no per frame storage/integration.
In 1911, Boris Rosing and his student Vladimir Zworykin created a system that used a mechanical mirror-drum scanner to transmit, in Zworykin's words, "very crude images" over wires to the "Braun tube" (CRT). Later some Dutch people used CRTs with the mechanical "Baird" system, before Baird used a CRT. Radio Fax was also used after hours in the USA on MW. Wired fax was first demonstrated about 1851. About 1909 saw a matrix of selenium cells used as a very low resolution camera. Colour transmissions on mechanical TV were in Germany about 1924.
Zworykin's big breakthrough was that each part of the camera target integrated over the entire frame interval, not just at the instant of reading (Farnsworth).
Electricity and photography gave inventors and scientists the impetus to pursue the technological realisation of "seeing at a distance" in old fairy tales.
Long distance "ẅriting at a distance" preceded electricity with Chappe in 1792. By the time of the Napoleonic War the networks stretched thousand of miles in Europe. Fictionalised in Terry Prachett's Discworld as the Clacks.
So the ingredients of TV were:
1799: Batteries and start of Electrical Age.
Movie film (a big spur) in late 1890s as development from photography in 1822.
1897 CRT
Marconi commercialising Maxwell & Hertz for radio in 1890s
Hot cathode CRT 1922
Maxwell on need only for R G B (mid 1800s) for Colour TV.
Amplifying valves (Edison, DeForest, Fleming etc)
Zworykin's camera tube was the final bit of the puzzle. The 1951 Colour was inevitable.
By the 1970s there was experimentation with Digital TV encoding and lasers on fibre optics for communication.
Semiconductor research predates valves. 1948 simply needed pure enough materials!
