This updated second edition includes new material throughout, especially though, in the areas of solid-state lasers, semiconductor lasers, and laser cavities. Simple explanations lead the reader logically from the basics of laser action to advanced topics in laser physics and engineering in this comprehensive introduction to the physical and engineering principles of laser operation and design. Direct explanations, examples, and many homework problems make this book invaluable to undergraduate and first-year graduate students taking courses on lasers. Summaries of key types of lasers, use of unique theoretical descriptions, and an extensive bibliography also recommend this volume to researchers.