Laser beam is used for various processing of materials, such as drilling, cutting, scratching, welding, heat treatment and so on.Some materials with metastable energy level will absorb light energy under the excitation of foreign photons, so that the number of atoms in high energy level is greater than the number of atoms in low energy level -- the number of particles reverses. If there is a beam of light shining, the energy of the photon is equal to the corresponding difference of these two energies, then stimulated radiation will be generated and a large amount of light energy will be output.
 

Laser technology is a comprehensive technology involving optical, mechanical, electrical, material and detection and other disciplines. Traditionally, its research scope can be generally divided into the following 9 aspects:

1. Laser processing system.Including laser, light guide system, machine tools, control system and detection system;

2. Laser processing technology.Including welding, surface treatment, drilling, marking, fine tuning and other processing technology;

3. Laser welding: automobile body thick and thin plates, automobile parts, lithium batteries, pacemakers, sealed relays and other sealed devices, as well as a variety of devices that do not allow welding pollution and deformation.The lasers used are YAG laser, CO2 laser and semiconductor pump laser.

4, laser cutting: automotive industry, computer, electrical cabinet, wood die cutter, cutting various metal parts, and special materials, circular saw blades, the force that press a gram, spring washers, electronic parts under 2 mm with some metal plates, steel pipes, tin-coated copper plate, plate, lead plate, phosphor bronze plating, electricity boards, thin aluminium alloy, quartz glass, silicon rubber, below 1 mm alumina ceramic pieces, aerospace industry use of titanium alloy and so on.There are YAG laser and CO2 laser used.

5. Laser marking: Widely used in all kinds of materials and almost all industries, the used lasers are YAG laser, CO2 laser and semiconductor pump laser;

6, laser drilling: laser drilling is mainly used in aerospace, automotive manufacturing, electronic instruments, chemical and other industries.With the rapid development of laser drilling, the average output power of YAG laser used for main body drilling has been increased from 400W to 800W to 1000W.The relatively mature application of laser drilling in China is in the production of artificial diamond and natural diamond drawing die, and in the production of gem bearings for clocks and instruments, aircraft blades, multi-layer printed circuit boards and other industries.Most of the lasers used are YAG lasers, CO2 lasers, but there are also some excimer lasers, isotope lasers and semiconductor pump lasers.

7. Laser heat treatment: widely used in the automobile industry, such as cylinder liner, crankshaft, piston ring, commutator, gear and other parts of the heat treatment, but also widely used in aerospace, machine tool industry and other machinery industry.The application of laser heat treatment in China is far more extensive than that in foreign countries.Most of the lasers used are YAG lasers and CO2 lasers.

8. Laser rapid prototyping: It is formed by combining laser processing technology with computer numerical control technology and flexible manufacturing technology, and is mainly used in mold and model industry.Most of the lasers used are YAG lasers and CO2 lasers.

9. Laser coating: widely used in aerospace, mold and mechanical and electrical industries.The lasers used are mainly high-power YAG laser and CO2 laser.