Radiophysics. Халюшева Г.Р. - 47 стр.

         12 Unit 12

         12.1 Text 12
                                                       Mysterious devices or not

          One of the most exciting fields of the twentieth century science is optical electropics.
          One of the most interesting and often talked about devices of our modern space age has been these science fiction
like laser and maser devices. Although these devices may have a mysterious and fantastic air about them they are basically
nothing more than energy amplifiers. The mystery lies in how electrons can be amplified in the laser and maser. Although
science fiction writers years ago imagined such things as ''ray guns" and "swords of heat" it was only in 1960 that the first
laser beam was actually created, its discoverer being Dr.Theodore H.Maiman.
       The laser is basically a device that controls the way in which photons are emitted
by a light source, and it produces a beam having much greater intensity and coherence
than one from any other source of light.
           Atoms emit rays of different length which prevents the forming of an intense beam of light. The laser forces its
atoms to emit rays having the same length and travelling in the same direction. The result is a narrow, extremely intense
beam of light that spreads out very little and is therefore able to travel very great distances.
           Early uses of the laser have been in optical radar, the cutting and welding of metals and as the basis of a branch of
photography called holography, which produces three dimensional images. Future uses of the laser beam may include
carrying millions of radio and television frequencies in a thousandth of a second. The controlled light from the laser beam is
to conventional sources of light what nuclear power is to traditional explosives. Power densities many milions of times more
intense than those on the surface of the sun can be produced, and yet laser beams can be so delicately controlled as to be
used to operate on the human eye.
           The laser's potentialities in science and technology are formulated in terms of four basic categories: how the device
offers advantages in welding, chemistry, spectroscopy, interplanetary signalling radar and communications.
           It is academician N.G.Basov the Russian physicist who is one of the founders of quantum radio physics. He
worked out a thoroughly new method of generating electromagnetic oscillations by means of quanta systems. He created the
first in the world molecular generator (maser). He put forward the idea of applying semiconductors for lasers and developed
the method of designing semiconductor lasers. N.G.Basov and A.M.Prokhorov, his collaborator became Nobel Prize
winners in 1964.
           The existing applications of lasers are numereous. For high precision welding and machining three dimensional
photography of undreamed realism communications on earth through space for location, navigation and as an aid to gunnery
they are already irreplaceable. They are moreover an entirely new tool for scientific research.
           Mention should be made that their potential and future exploration is limitless.
           Three dimensional television and cinema, wide and dramatic uses in surgery, X–ray laser beams and laser
computers are only a few of the possibilities which must now be seriously considered.
           Certainly for many years to come lasers will continue to merit the description given to them immediately on their
discovery – "A solution is in search of a problem."

         12.2 Words and word–combinations to be remembered



         Optical electronics – оптическая электроника
         science fiction – научная фантастика
         laser – лазер, квантовый усилитель. Слово "лазер" состоит из начальных букв фразы, описывающей
         функцию прибора: light amplification by stimula-ted emission of radiation – усиление света посредством
         стимулирования эмиссии излучений
         amplifier – усилитель
         to lie in – заключаться в
         to amplify – усиливать
         to imagine – представлять; воображать.
         gun – пушка
         sword – шпага; меч.
         intensity – интенсивность, напряжённость; сила, энергия.
         coherence – когерентность