What are the components of a Laser?

• A. Power Pumping Station; Active Medium; Optical Cavity
• B. Energy Source; Gain Medium; Mirror
• C. Power Supply; Coupling Junction; Reflector
• D. Pumping Source; Active Layer; Prism

Answer: (A)

A laser works because three essential parts come together: an energy source to pump the gain medium, a gain medium where amplification happens, and an optical cavity that provides feedback to build up light. The energy source injects energy to raise the atoms in the gain medium to excited states, creating population inversion so stimulated emission can dominate. The gain medium then amplifies light as photons stimulate more emission, producing the amplified beam. The optical cavity, formed by mirrors, reflects light back and forth so it resonates, reinforcing the light and selecting the desired modes. Some other terms shown—like a single mirror, a prism, or generic components—don’t capture the full, necessary trio for sustained, coherent laser operation.