Where did lasers come from?

The theory of laser(Laser Amplification by Stimulated Emission of Radiation) sprung from Albert Einstein in 1917, who pointed a series of technical theory about the interaction between light and substance (Zur Quantentheorie der Strahlung).

According to the theory, there’re different numbers of particles distributed at different energy levels. And the particles at high energy level will jump to the low energy level when excited by a certain photon. At a low energy level, light of the same nature as the light that excites it will be radiated. And a week light can excite a strong light in a certain state.

After that, Rudolf W.Ladenburg, Valentin A. Fabrikant, Willis E. lamb, Alfred Rastler Joseph Weber and many researchers made contributions in the exploration of lasers.

Today, I would like to pay more attention to the application of lasers, like laser cutting and engraving, laser welding and laser marking. The application of laser cutting started in 1963, it was popular with four advantages, high lightness, high direction, high monochromaticity and high coherence. There’s no deformation and tool wear during the operation since the laser doesn’t contact with the processing material. Further, it’s a flexible processing that quickly cut and pierce the metal material with high intensity of beam and powerful energy.

What’s more, if you have ever heard laser welding, a new substitution of conventional welding, you would know it is an effective way. Not only because of the great adaptability, but also because of the comprehensive advantages.

Based on the optical laser beam, workers could weld the metal material without the filler and the welding flux. Compared with traditional argon arc welding, the most common way of welding right now, fiber laser welding could pass through the transparent material, which could greatly prevent he injury by the distant processing. And it could be used in the extreme environment, like high temperature, high cold and radioactive environment.