LEDs
In the last century was the
invention of light bulb filament, and in the thirties of this century -
a series of neon fluorescent lamps, the impression, thus the needs of
humanity in the sources of artificial lighting are satisfied with a good
long time. But everyone knows that the ideal "final" resolution of the
technique is as rare as the sinless people, so to achieved - and the
advantages and disadvantages - adjust, then get used to and begin to
perceive all this for granted.
Even in 1923, our countryman OV Losev, conducting radio research,
noticed a bluish glow emitted by some semiconductor detectors. In this
case the heating element design was not, are born inside the silicon
carbide crystal is due to the unknown time electronic transformations.
However, the intensity of radiation was so insignificant that the
scientific community is actually "not see" it, at least in a figurative
sense. In electronics in those days were much any importance.
Only forty years later, seriously addressed the problem of the
semiconductor world. " And in the mid-sixties there were LEDs - tiny
plastic fireflies red, yellow, greenish glow. Ideal detectors of "on-off",
they immediately caught the fancy of designers of radio and soon lit on
the front of radios, tape recorders, televisions, computers, as well as
refrigerators, washing machines, technological units. Already in the
mid-seventies, the world production of LEDs overstepped billion mark,
and now - dvadtsatipyatimilliardnuyu. But the problem of lighting all
this had nothing to do.
After the breakthrough occur weekdays, during the "small cases", which
sometimes prove to be not quite so and small. Research of Academician
Jaures Alferov and some foreign scholars have shown that if the finest
produce semiconductor structure with alternately varying properties, it
is possible to accumulate electrons in a strictly defined areas and
thereby improve the efficiency of converting electrical energy into
light. More - more. When first seen, and even microscopic, but the
crystal, they soon have to go through the individual atoms. Flashed
intricate concepts such as "quantum well", "superlattice", "Two-dimensional
liquid ... Physicists once again learned about semiconductors, "almost
all", and technologists learn how to do more than "all".
Sooner or later, "the period of primitive accumulation" is completed -
in the early nineties, a little known Japanese firm Nure threw LEDs on
the market is ten times brighter than all their predecessors. And this
was all the colors, which had previously lacked: lush-green, blue,
purple, white, finally. Semiconductor palette gleamed with all the
colors of the rainbow. LEDs "came" from the premises on the street
without fear, as before, the solar flare. In a short time semiconductor
lights subdued center of Moscow (they are easily recognizable by their
purity and homogeneity of the glow) and went to the cities and villages
of Russia.
Of course, the traffic light - this is not lighting, but since 1998 the
Americans from Hewlett Packard began producing light-emitting diodes,
suitable for lighting the car. Their light output is better than
incandescent lamps, and resource improvement is far from exhausted.
Semiconductor light-emitting diodes determines the essence of the new
and unique advantages. First, it is very small dimensions, strength,
ability to light up the voltage of only a few volts, practically
unlimited durability. And besides, the brightness of the emission of any
very pure color, simple regulation of luminescence. LED bulbs can be
embedded in any, even remote, locations, they are absolutely safe, they
do not need bullets for screwing, soldered - and forever.
While LEDs are not threatened to incandescent lamps in our homes. But it
is very likely that in the near future it will happen. And then our
charges for electricity will be just symbolic. And the designers of our
future homes will have an excellent tool for the realization of their
creative imagination, pity, though, seem to wither away crystal
chandeliers, this symbol of strength and warmth of family ties.
Yury Nosov, professor, doctor of technical sciences.
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