The present collection of articles sets forth the results of experimental research on physical processes in various types of optical quantum devices (lasers). Data are presented on the regulation of the temporal and spectral characteristics of solid-state lasers using a bleachable filter. A mode self-locking state is realized in which ultraflhort light pulses are emitted. The stimulated emission in a pinch discharge due to transitions of singly and doubly ion­ ized argon atoms in the visible and ultraviolet parts of the spectrum is investigated. Pulsed lasing associated with electron transitions in diatomic molecules at the leading edge of a power­ ful current pulse in a gas is subjected to systematic analysis. The book is aimed at a broad spectrum of scientists and engineers specializing in quan­ tum radiophysics. CONTENTS MODE DISCRIMINATION AND THE SELF-LOCKING EFFECT IN SOLID-STATE LASERS USING A BLEACHABLE FILTER A. S. Markin Introduction 1 Chapter 1. Q S wit chi n g 0 f Las e r s by Mea n s 0 f a Pas s i v e Shu t t e r. . . . 5 1. Operating Principle and Types of Passive Shutters. . . . . . . . . . . . . . . . . . . . 5 2. Q Switching of Neodymium Glass Lasers by Means of a Bleachable Liquid Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3. Dependence of the Width and Shape of the Giant Pulse on the Population Inversion Coefficient. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .