Laser Cavity: Optical Gain and Resonators

This lecture covers the fundamental concepts of laser cavities, including open optical resonators, curved mirror resonators, and diffraction losses. It explains the importance of achieving population inversion for optical gain and the unique properties of laser radiation. The instructor discusses the design and operation of laser oscillators within optical cavities, emphasizing the role of stimulated emission. The lecture also delves into stability conditions for open resonators, ray tracing in optical systems, and diffraction phenomena in laser resonators. Additionally, it explores the Kirchoff-Fresnel diffraction integral formula and the resolution limit in grating spectrometers. The presentation concludes with a detailed analysis of transverse electromagnetic modes (TEM) in laser cavities.