What does the acronym LASER stand for?

The acronym LASER stands for "Light Amplification by Stimulated Emission of Radiation." This term captures the essential function and principle behind how lasers operate. In essence, a laser generates a concentrated beam of light by amplifying photons through stimulated emission, a process where excited atoms release energy in the form of light when stimulated by incoming photons.

This process is fundamental to the technology's effectiveness in numerous applications, ranging from medical procedures to cutting and welding applications, as well as in various forms of communication. The definition emphasizes both the method of amplification and the nature of the emitted light, which is coherent and monochromatic, distinguishing lasers from other light sources.

The other options do not correctly describe the technology and miss key components of how lasers function, leading to misunderstandings of their operation and applications.