|Bookmark this page! |
word television derives from the Greek tele, for “far,” and the Latin visio,
meaning “sight.” Many people believe the television was invented in one
instance by one person, but, in fact, it was a culmination of several
discoveries over a period of time.
Scanning images to transmit them via electrical signals was first performed in
1881 with a pendulum-like device and a German student, Paul Gottlieb Nipkow,
patented a device in 1884 that scanned images via a spinning disk with angular
holes that spun light over a selenium sensor. This produced electrical charges
that could be sent through wire or airwaves. Advanced as this notion seems,
there was no practical way to reconstitute the images until 1907 when
amplifier tubes came into use.
In 1926, John Logie Baird successfully transmitted images from a drum scanning
device to a cathode ray tube display at 30 lines of resolution via telephone
line from Glasgow to London. Kalman Tihanyi invented a system using only
electronic scanning later that same year and Russian Leion Theremin had
increased resolution to 100 lines by 1927. Also in 1927, Philo Farnsworth
developed the first electronic scanner and display. It was revealed to the
press in 1928 and in 1934 he was able to remove the last of the mechanical
parts. A significant patent battle developed between Farnsworth and Vladimir
Zworykin who independently developed a similarly working system from his own
lab. After Zworykin was unable to produce a working model, the U.S. patent
office gave the patent solely to Farnsworth in 1939. However, Isaac Shoenberg
later used Zworykin’s design to produce the first BBC cameras in 1936.
Television resolution was at its peak in Britain with Shoenberg’s system that
produced 405 lines. It was not topped until 1944 when the Soviet Union began
using technology producing 625 lines which later became the European standard
in the late 1940s. After the increase in resolution, the next major innovation
was electronic color television with the first fully-functional model being
demonstrated by Baird in 1944.
Broadcast television would not change substantially for most consumers until
the 1990s when the analog signals began to be digitized and primarily
delivered through wired subscription cable services and satellite
transmissions and the first decade of the 21st century saw the death of the
cathode ray tube television with the advent of LCD and plasma technology.
| Television - probably the largest choice of Television in the UK!
drivers cheap car insurance car
insurance in the uk student
car insurance cheap
car insurance companies instant
car insurance quote cheap