The History Of Electronics
The history of electronics is a story of the twentieth century and three key components—the vacuum tube, the transistor, and the integrated circuit. In 1883, Thomas Alva Edison discovered that electrons will flow from one metal conductor to another through a vacuum.
This discovery of conduction became known as the Edison effect. In
1904, John Fleming applied the Edison effect in inventing a two-element electron tube called a diode,
and Lee De Forest followed in 1906 with the three-element tube, the
triode. These vacuum tubes were the devices that made manipulation of
electrical energy possible so it could be amplified and transmitted.
The first applications of electron tubes were in radio
communications. Guglielmo Marconi pioneered the development of the
wireless
telegraph
in 1896 and long-distance radio communication in 1901. Early radio
consisted of either radio telegraphy (the transmission of Morse code
signals) or radio telephony (voice messages). Both relied on the triode
and made rapid advances thanks to armed forces communications during
World War I. Early radio transmitters, telephones, and telegraph used
high-voltage sparks to make waves and sound. Vacuum tubes strengthened
weak audio signals and allowed these signals to be superimposed on
radio waves.
In 1918, Edwin Armstrong invented the "super-heterodyne receiver" that
could select among radio signals or stations and could receive distant
signals. Radio broadcasting grew astronomically in the 1920s as a direct
result. Armstrong also invented wide-band
frequency modulation (FM) in 1935; only AM or amplitude modulation had been used from 1920 to 1935.
Communications technology was able to make huge advances before World
War II as more specialized tubes were made for many applications. Radio
as the primary form of education and entertainment was soon challenged
by television, which was invented in the 1920s but didn't become widely
available until 1947. Bell Laboratories publicly unveiled the television
in 1927, and its first forms were electromechanical. When an electronic
system was proved superior, Bell Labs engineers introduced the
cathode ray picture tube and
color
television. But Vladimir Zworykin, an engineer with the Radio
Corporation of America (RCA), is considered the "father of the
television" because of his inventions, the picture tube and the
iconoscope camera tube.
Development of the television as an electronic device benefitted from
many improvements made to radar during World War II. Radar was the
product of studies by a number of scientists in Britain of the
reflection of radio waves. An acronym for
RAdio
Detection
And
Ranging, radar measures the
distance and direction to an object using echoes of radio microwaves. It is used for
aircraft
and ship detection, control of weapons firing, navigation, and other
forms of surveillance. Circuitry, video, pulse technology, and microwave
transmission improved in the wartime effort and were adopted
immediately by the television industry. By the mid-1950s, television had
surpassed radio for home use and entertainment.
After the war, electron tubes were used to develop the first
computers, but they were impractical because of the sizes of the
electronic components. In 1947, the transistor was invented by a team of
engineers from Bell Laboratories. John Bardeen, Walter Brattain, and
William Shockley received a Nobel prize for their creation, but few
could envision how quickly and dramatically the transistor would change
the world. The transistor functions like the vacuum tube, but it is tiny
by comparison, weighs less, consumes less power, is much more reliable,
and is cheaper to manufacture with its combination of metal contacts
and semiconductor materials.
The concept of the integrated circuit was proposed in 1952 by
Geoffrey W. A. Dummer, a British electronics expert with the Royal Radar
Establishment. Throughout the 1950s, transistors were mass produced on
single wafers and cut apart. The total semiconductor circuit was a
simple step away from this; it combined transistors and diodes (active
devices) and capacitors and resistors (passive devices) on a planar unit
or chip. The semiconductor industry and the silicon integrated circuit
(SIC) evolved simultaneously at Texas Instruments and Fairchild
Semiconductor Company. By 1961, integrated circuits were in full
production at a number of firms, and designs of equipment changed
rapidly and in several directions to adapt to the technology. Bipolar
transistors and digital integrated circuits were made first, but analog
ICs, large-scale integration (LSI), and very-large-scale integration
(VLSI) followed by the mid-1970s. VLSI consists of thousands of circuits
with on-and-off switches or gates between them on a single chip.
Microcomputers, medical equipment, video cameras, and communication
satellites are only examples of devices made possible by integrated
circuits.
Nearly all video games include some level of artificial intelligence.
The most basic type of AI produces characters that move in standard
formations and perform predictable actions. More advanced artificial
intelligence enables computer characters to act unpredictably and make
different decisions based on a player's actions. For example, in a
first-person shooter (FPS), an AI opponent may hide behind a wall while
the player is facing him. When the player turns away, the AI opponent
may attack. In modern video games, multiple AI opponents can even work
together, making the gameplay even more challenging.
