Technical College national university

"Lviv Polytechnic"

Abstract

On the topic: "The importance of opening a laser and its capabilities"

Completed: student 31KI

Kobrinovich R. V.

Accepted:

Fedina N. D.

Lviv 2019

Content

Introduction

History of the invention of the laser

Application in medicine

Application of laser beam in industry

Application of lasers in computer engineering

References

Introduction

A laser is a device for generating or amplifying monochromatic light, generating a narrow beam of light capable of propagating over long distances without scattering, and creating an extremely large radiation power density when focusing.

Lasers have come into human life and life in a relatively short time. The creation of the laser was preceded by a long history. The invention of this useful device humanity owes to radiophysicists, namely Alexander Prokhorov and Nikolai Basov. Through the research of these scientists, a new page in the history of technical science was opened. Of course, over time, studies of Soviet scientists, in turn, were replenished with new ideas of American physicists who have increasingly refined this device. The first ruby ​​laser created by American scientist Maiman made a huge impression on others. In addition to ruby, many other compounds can be used as active substances in lasers.

Java's invention of a gas laser is interesting. However, the most important thing in the end was the invention in 1962 by Soviet physicists of a semiconductor laser.

History of the invention of the laser

In 1964 Prokhorov, Bass and Towns were awarded the Nobel Prize in Physics "for fundamental work in quantum electronics that led to the creation of oscillators and amplifiers based on the laser-maser principle." At first, after the invention, it was believed that the maser was a purely human creation, but later astronomers discovered that some of the distant galaxies function as giant masers. The huge gas clouds, the size of billions of kilometers, create the conditions for generation, and the source of pumping is cosmic radiation. Masers are used in engineering, in physical research, as well as standard frequency quantum generators.

Interestingly, the first microwave generator, an ammonia maser, was created in 1954. The role of feedback was played by a three-dimensional resonator, the dimensions of which were about 12.6 mm (the wavelength emitted during the transition of ammonia from the excited oscillatory level to the main one). To amplify the electromagnetic radiation of the optical range, it was necessary to create a three-dimensional resonator whose dimensions would be in the order of microns. Due to the technological difficulties involved, many scientists at the time believed that it was impossible to create a visible radiation generator.

The work of the first optical quantum generator (laser) was demonstrated on May 16, 1960. The artificial ruby ​​crystal was used as the active medium, and the Fabry-Feather resonator formed by silver mirror coatings deposited at the end of the crystal served as a volumetric resonator. This laser operated in pulsed mode at a wavelength of 694.3 nm. In December of the same year, a helium-neon laser was created, which emits in a continuous mode. Initially, the laser operated in the infrared range, then was modified to emit visible red light with a wavelength of 632.8 nm.

The physics of lasers is still intensively developing. Since the invention of the laser, almost every year its new types, adapted for different purposes. In 1961, a neodymium glass laser was created, and over the next five years, laser diodes, dye lasers, carbon dioxide lasers, and chemical lasers were developed. In 1963, J. Alferov and G. Kremer (Nobel Prize in Physics 2000) developed the theory of semiconductor hetero structures, on the basis of which many lasers were created.

The unique properties of laser radiation have made it possible to use them in various fields of science and technology, for example, in optical communication systems.