Laser is another great invention after nuclear energy, computer and semiconductor since the 20th century. It is called "the fastest knife", "the most accurate ruler" and "the brightest light". The English name of radiation stimulated emission amplification means "stimulated radiation amplification".
The theoretical basis of laser originates from physicist Einstein. 19 17, Einstein put forward a brand-new technical theory of the interaction between light and matter. This theory means that there are different numbers of particles (electrons) distributed in different energy levels in the atoms that make up the matter, and the particles at the high energy level will jump (jump) from the high energy level to the low energy level when excited by a photon.
At this time, it will emit light with the same properties as the light that excites it, and under certain conditions, weak light can also excite strong light. This is called "optical amplification of stimulated radiation", or laser for short.
Extended data:
Microscopically, laser is a collection of a large number of photons with the same frequency, and the key to obtaining excellent laser performance is to make all photons have the same frequency. This can be achieved by a laser resonator.
After we add photons with a specific frequency to the laser resonator, the atoms in it can oscillate at the frequencies of these photons, thus emitting photons with the same frequency. This physical process, similar to the "chain reaction" of an atomic bomb, enables us to quickly obtain a large number of photons with a certain frequency, which can be emitted in the form of laser after modulation.
The application of laser, in addition to the widely used information detection and information transmission technology, also operates some tiny structural objects through the interaction between photons and material particles.
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People's Network-Man's Exploration of Laser