I am very pleased to have completed this Second Edition of Laser Fundamentals. The encouragement I have received over the past few years from readers as well as from my editors was sufficient to provide me with the enthusiasm to take on this new task. Writing the first edition was essentially a ten-year endeavor from first thoughts to the completed book. I thought I had a better way to explain to senior-level and first-year graduate students how lasers work. Apparently there were others who agreed with me, judging from comments I have received. Writing the second edition was an attempt to fill in some of the gaps, so to speak; not surprisingly, it took much more time than I had anticipated. Some of the areas of the First Edition were not as complete as I would have liked. There were also errors that had to be corrected. In addition, there have been advances– primarily in the areas of solid-state and semiconductor lasers– that needed to be included. I think the new edition addresses those issues pretty well. I suppose it's up to the readers to make that judgment.

Naturally one canyt take on a task like this without gleaning information from experts in the various fields of lasers. I offer special thanks to my colleagues at the School of Optics/CREOL at the University of Central Florida: Michael Bass, Glenn Boreman, Peter Delfyett, Dave Hagan, Hans Jenssen, Patrick Li Kam Wa, Alexandra Rapaport, Kathleen Richardson, Martin Richardson, Craig Siders, Eric Van Stryland, Nikolai Vorobiev, and Boris Zeldovich.

I wrote Laser Fundamentals with the idea of simplifying the explanation of how lasers operate. It is designed to be used as a senior-level or first-year graduate student textbook and/or as a reference book. The first draft was written the first time I taught the course “Laser Principles” at the University of Central Florida. Before that, I authored several general laser articles and taught short courses on the subject, giving careful consideration to the sequence in which various topics should be presented. During that period I adjusted the sequence, and I am now convinced that it is the optimal one.

Understanding lasers involves concepts associated with light, viewed either as waves or as photons, and its interaction with matter. I have used the first part of the book to introduce these concepts. Chapters 2 through 6 include fundamental wave properties, such as the solution of the wave equation, polarization, and the interaction of light with dielectric materials, as well as the fundamental quantum properties, including discrete energy levels, emission of radiation, emission broadening (in gases, liquids, and solids), and stimulated emission. The concept of amplification is introduced in Chapter 7, and further properties of laser amplifiers dealing with inversions and pumping are covered in Chapters 8 and 9 [Chapters 8–10 in the Second Edition – Ed.]. Chapter 10 [11] discusses cavity properties associated with both longitudinal and transverse modes, and Chapters 11 and 12 [12 and 13] follow up with Gaussian beams and special laser cavities.