The word "laser" has so firmly entered our lives that, probably, every adult inhabitant of the planet knows about these devices. The use of lasers has become familiar and almost everyday. It is used in many fields of human activity .
American physicists working in the famous laboratory to them. Lorentz, claim that they were able to reproduce an unprecedented in magnitude ray. The laser power is 500 trillion watts and 1.85 Mega joules of ultraviolet radiation. The invented beam has a magnitude of only 2 mm in diameter, but its power is greater than that possessed by all energy-consuming devices in America working simultaneously. The laser temperature is 100 million degrees, and this is more than in the center of the main energy source - the Sun.
What is a laser? This is a source of electromagnetic radiation, which is based on the stimulated emission of molecules and atoms. It includes the visible, infrared and ultraviolet ranges, is characterized by a very high directivity of radiation, which is its unique ability.
The use of lasers is diverse. It is used in such areas of human activity as medicine, biology, military industry, location and communications, information storage, space distance measurement, projection television, high technology and much more. Thanks to the laser, scientists today possess monochromatic light of any wavelength. It can be continuous radiation with a narrow spectrum or an ultrashort pulse.
The following types of lasers are known:
- gas;
- solid state;
- liquid.
A ruby laser functions in an alternating pulsed mode , but in gas, the main working substance, of course, is gas. Its atoms receive momentum from an electric discharge.
There are semiconductor lasers that relate to continuous devices. The radiation energy is taken from them by electric current. Gas dynamic lasers also exist. They are very powerful, have the same basis, are characterized by continuous action. Their principle of operation is based on the process of cooling supersonic gas flows.
Known types of lasers are divided into several types, depending on what substance they work on: dyes, gas, metal vapor or semiconductor.
Originally used modern astronomers laser and get an amazing result. They determined the exact distance to the Earth’s satellite - the Moon, and used a ruby laser and corner reflectors for this bold experiment. Scientists sent a focused laser from the Earth’s surface using a telescope. From the time taken to get to the moon and back, the exact distance was determined.
In medicine, the use of lasers is incredibly wide. With their help, people return the opportunity to live a full life. An example is retinal surgery, during which doctors use the same laser instead of a scalpel. In addition, this source of electromagnetic radiation is used to treat severe bone injuries, as well as during surgical interventions when the connection of torn muscle tissue is required.
Biologists using laser tweezers have gained new opportunities in the field of protein research. Laser magnetization is widely used, as well as the cooling of molecules when it is necessary to use ultra-low temperatures. The use of lasers in thermonuclear fusion, surface treatment, heat treatment and hardening of metals is known , and, in addition, in the production of modern weapons. For example, in 2009, the American company Northrop Grumman created a solid-state electric laser with a power of 100 kW. The development was intended to combat air and ground targets during the defense of the country.