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| TOP PAGE > P2 Dawn of TV Technology |
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Dawn of TV Technology:
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| In the 19th century, humans ascertained the existence of electricity and radio waves. Marconi invented radiotelegraphy in 1895. Ten years later, the vacuum tube was invented, which eventually led to the development of radio. While all communications technology advancements have affected peoples’ lives, radio can especially be considered an epoch making invention, since it drastically reduced the time needed for the delivery of information. | |||||||||||||||||||||||||
| 1840 Information first transmitted by Electricity | |||||||||||||||||||||||||
| Tele(far off)-Phone(to hear)
/ Tele(far off)-Vision(to see) Since ancient times, humans have dream of distant lands. Hearing and seeing events occurring far away had not been possible for ordinary people, prompting at least a limited interest in clairvoyance or crystal ball gazing in various parts of the world. It was in the 19th century that the dreams of the tele(far off)-phone(to hear) and television(to see) started to be given thought from a scientific standpoint and to be considered subjects for technical proof. Discovery of Electricity The latter half of the 19th century can especially be seen as the dawn of information and communications technology. It was at this time that certain natural phenomena, which had previously been considered a mystery, were elucidated. Already in the 18th century, the existence of electricity had been ascertained. For example, Gennai Hiraga, a samurai from the Takamatsu domain, had constructed the first friction generator, Elekiter, in Japan, based on the knowledge he acquired from studying an imported electric generator at Nagasaki. Around 1800, Allesandro Volta of Italy verified that a continuous electrical current could be generated by a piece of paper dampened with salt water and placed between copper and zinc plates. This was the basic principle of batteries and proved to be a first step toward making the 20th century the “century of the moving image.” Invention of Morse Code About 1840, Samuel F.B. Morse of the United States invented a means of telegraphic communication that converted words into a code consisting of dots and dashes, which could be transmitted by simple electrical pulses. This code came to be known as Morse code. The expectations for electrical communication quickly grew; Commodore Matthew Perry, who visited Japan for the second time in 1854, demonstrated a Morse telegraph to the Shogunate. Discovery of Radio Waves: the Success of Wireless Communications Once the feasibility of wired electrical communication had been shown, studies to transmit information wirelessly accelerated. Regarding the existence of invisible radio waves, Heinrich Hertz of Germany was first to detect the electromagnetic field generated by electrical oscillations (in 1887), and showed (in 1888) that the characteristics of radio waves are identical to those of light. This discovery of radio waves increased interest in the possibility of wireless communications. The first successful wireless communications experiment was conducted by Guglielmo Marconi of Italy in 1895, when he transmitted a Morse code signal from a window in his house to a point 2.4 km distant. The following year, Marconi moved to Britain, and here his work eventually culminated in the first transatlantic (3,600-km) radio transmission in 1901. First Human Voice Rides on a Radio Wave The latter part of the 19th century was indeed an era of media proliferation. In 1876, Alexander Graham Bell of the United States invented the telephone, a device for converting the human voice into electricity and vice versa. This was followed by the invention of the phonograph by Thomas Edison in 1877. The first radio wave to transmit a human voice was emitted in a suburb of Boston, U.S., by Canadian-born Reginald Fessenden on Christmas Eve, 1906. |
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 Demonstration of Morse telegraph (above)
by Commodore Perry at Yokohama (reproduction) (1854) Discovery of electromagnetic waves: the basis for wireless telegraphic communication |
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