Electron Beams, Lenses, and Optics, Volume I deals with the physics of electron beams, lenses, and optics and covers topics ranging from the paraxial ray in symmetrical electric fields to the analytical determination of electrostatic fields. The general properties of electrostatic lenses and the electrostatic immersion lens are also considered. Each equation except one is derived from first principles. To emphasize the physics of the discussions, elementary mathematics is used as much as possible. Comprised of eight chapters, this volume begins with an introduction to the laws that govern electron beams and light rays, including Snell's law. Some fundamental limitations to the analogy between electron optics and light optics are evaluated, together with electron rays in plane symmetrical and in rotationally symmetrical fields. Subsequent chapters explore the general properties of electrostatic lenses and electrostatic immersion lenses; electrostatic unipotential lenses; and formation of optical images by rotationally symmetrical magnetic fields. The final chapter is devoted to the symmetrical magnetic lens and its magnetic scalar potential, paying particular attention to the flux density along the z axis and factors to consider in the design of the pole pieces. This book will be of interest to students, practitioners, and researchers in physics.