What is the principle of laser?

1. Introduction to laser

The English name of the laser is LASER, which is an acronym for "light amplification by stimulated emission of radiation" (light amplification by stimulated emission of radiation).

2. The principle of laser generation

When the electrons in the atom absorb energy and then transition from a low energy level to a high energy level, and then fall back from a high energy level to a low energy level, the released energy is released in the form of photons. The photon beam (laser) that is lured (excited) has a highly consistent photon optical characteristic. Therefore, the laser has better monochromaticity, directivity and higher brightness than ordinary light sources.

3. Advantages of laser

Good monochromaticity: The wavelength distribution range of the light emitted by the laser is narrow, so the color is extremely pure. The monochromaticity of laser is far stronger than other monochromatic light sources.

Good monochromaticity can facilitate filtering and improve the signal-to-noise ratio. In material processing, the absorption spectra of different materials are different, and the monochromaticity of the laser can well control the absorption depth and distribution, and the materials can be processed selectively and in a controlled manner. Monochromatic light is much more convenient in optical design, there is no difference in dispersion, and the better the monochromaticity, the more stable the corresponding wavelength or frequency.

Strong directivity: The beam emitted by the laser only emits in one direction. Ordinary light sources are mostly scattered in all directions. If you want to make the light source converge to one part, you need to install auxiliary devices. For example, the headlights of automobiles are equipped with light-gathering reflectors to make the light converge and emit in one direction.

The laser light emitted by the laser is only emitted in one direction, and the divergence of the beam is extremely small, almost parallel. The distance between the earth and the moon is about 380,000 kilometers. If a beam of light is sent to the moon, but the laser spot on the moon's surface is less than two kilometers, the seemingly parallel searchlight beams shoot toward the moon, and the spot diameter will cover the entire moon.