Is laser a type of electromagnetic wave?

Laser is a special type of light and fundamentally belongs to electromagnetic waves. Electromagnetic waves are oscillatory phenomena produced by the interaction of varying electric and magnetic fields, and they can propagate through a vacuum. As a form of electromagnetic wave, laser typically has wavelengths within the visible, infrared, or ultraviolet spectrum.

The generation of laser is based on the principle of stimulated emission. When atoms or molecules transition from a higher energy level to a lower energy level, they emit photons, which are the fundamental units of light energy. In a laser device, a specific excitation process brings numerous atoms or molecules to the same high energy level, thereby achieving amplification of stimulated emission and forming a high-energy-density laser beam.

Therefore, the unique characteristics of lasers lie in the high coherence of their photons in terms of frequency, phase, polarization direction, and direction of propagation, endowing lasers with distinctive properties and application value. Due to these special properties, safety precautions must be taken during laser use to avoid direct exposure to the eyes and prevent potential injury.