Application in medicine

Lasers are widely used in medicine, especially in ophthalmology, surgery and oncology, capable of creating a small spot, due to their high monochromaticity and focus. In ophthalmology, laser radiation with an energy of 0.2 - 0.3 j allows for a number of complex operations without breaking the integrity of the eye itself. One such operation is the welding and strengthening of the detached retina by coagulation adhesions. In addition, the laser beam is used to burn malignant and benign tumors. In surgery, the continuous beam of a continuous laser (up to 100 watts) is an extremely sharp and sterile scalpel that performs bloodless operations even on the liver and spleen. The use of continuous and pulsed lasers to burn wounds and stop bleeding in patients with reduced blood clotting has considerable potential.

The use of a laser scalpel for surgery determines the following properties:

- it produces a relatively bloodless incision because, at the same time as the tissue section, it coagulates the wound edges by "brewing" not very large blood vessels;

- the laser scalpel differs in the constancy of cutting properties. Contact with a solid object (such as a bone) does not disrupt the scalpel. For a mechanical scalpel, this situation would be fatal;

- the laser beam due to its transparency allows the surgeon to see the operated area. The blade of an ordinary scalpel, as well as the blade of an electric knife, always to some extent obstructs the working field from the surgeon;

- the laser beam cuts the fabric at a distance without having any mechanical effect on the fabric;

- the laser scalpel provides absolute sterility, because only radiation interacts with the tissue;

- the laser beam acts strictly locally, the evaporation of the tissue occurs only at the point of focus.

Adjacent tissue areas are damaged much less than using a mechanical scalpel;

- as clinical practice has shown, the wound from the laser scalpel almost does not hurt and heals

faster.

The practical application of lasers in surgery began in the USSR in 1966 at the AV Vishnevsky Institute. The laser scalpel has been used in operations on the internal organs of the thoracic and abdominal cavities. Currently, the laser beam is made by skin and plastic operations, operations of the esophagus, stomach, intestines, kidneys, liver, spleen and other organs. It is very tempting to perform laser surgery on organs containing a large number of blood vessels, such as the heart, liver.

Application of laser beam in industry

Optical quantum generators and their radiation have found application in many industries. For example, in the industry there is a use of lasers for welding, processing and cutting metal and dielectric materials and parts in instrumentation, mechanical engineering and in the textile industry.

Beginning in 1964, low-productivity mechanical hole drilling was replaced by laser drilling. The term laser drilling should not be taken literally. The laser beam does not drill the hole: it pierces it through intense evaporation of the material at the point of impact.

Laser processing of metals. The possibility of receiving high-power light beams of up to 1012 -1016 W / cm2 by laser focusing with spot radiation up to 10-100 microns in diameter makes the laser a powerful means of processing optically opaque materials that are not available for conventional methods (gas and arc welding). This allows for new technological operations, such as drilling very narrow channels in refractory materials, different operations in the manufacture of film circuits, as well as increasing the speed of processing parts. When drilling holes in diamond circles, it reduces the machining time of one circle from 2-3 days to 2 minutes. The most widely used laser in microelectronics, where it is better to weld the joints rather than soldering. Main advantages: absence of mechanical contact, possibility of processing of inaccessible parts, possibility of creation of narrow channels directed at an angle to the work surface.

The laser is also used in the manufacture of fine wires of copper, bronze, tungsten and other metals. In the manufacture of wires, the technology of drawing (drawing) wire through holes of very small diameter is used. These holes (or drawing channels) are drilled in materials that have a particularly high hardness, for example, in superhard alloys. The hardest is known to be a diamond. Therefore, it is best to draw a thin wire through the holes in the diamond. Only they allow to get a wire with a diameter of only 10 microns. However, the mechanical drilling of one hole in the diamond takes 10 hours. But it is quite easy to punch this hole with a series of several powerful laser pulses. As in the case of punching holes in clock-type cameos, solid-state pulsed lasers are used to drill the diamond.

Laser drilling is widely used to obtain openings in materials that are highly brittle. As an example, the substrates of circuits made of alumina ceramics. Due to the high brittleness of ceramics, mechanical drilling is performed on "raw" material. Burn ceramics after drilling. There is some deformation of the product, the relative position of the drilled holes is distorted. When using "laser drills", you can safely work with ceramic substrates, have already passed firing.

Interesting use of the laser and as a universal soldering iron. Suppose an accident occurred inside the cathode-ray tube - any wire broke or broke, contact broke. The tube failed. It would seem that the breakage is irreparable, because the CRT is a device, all the internal components of which are in a vacuum, inside a glass cylinder, and no soldering iron there to penetrate. However, the laser beam can solve such problems as well. By directing the beam to the correct point and focusing it properly, welding work can be performed.