Anyone who has looked through binoculars, a telescope or microscope has used an eyepiece. Telescope Eyepieces: Optical Theory and Design explores the wide range of eyepiece designs. It introduces optics theory progressively to build understanding of how lenses control light in an optical system generally and in eyepieces specifically, linking optics fundamentals, design evolution and the implications for image quality. The book presents a logical narrative starting with Snell’s law of refraction at a flat surface, progressing to paraxial and real rays at spherical and aspherical surfaces, lenses and thin-lens systems. It demystifies the origin of aberrations by considering wavefront deviations, all brought to life in the context of the familiar eyepiece. Principles are explored both descriptively and mathematically, carefully interpreted so the reader is not swamped by a sea of equations. The book contains many diagrams of ray tracing results to illustrate optical principles and the consequences of design choices, enabling the reader to visualise their impact on image quality and to cut through the puffery that is sometimes found in the marketing of telescope eyepieces. The book bridges the gap between introductory astronomy books and expert-level optical design texts, written jointly for an astronomy readership and for physics and optical-design students.

Key Features:

• Develops an understanding of optics by focusing on the design variations of a particular multi-lens system – the eyepiece – which readers will have used when looking through binoculars, telescopes and microscopes.
• Combines descriptions and interpretations of theory with many illustrative visualisations of eyepiece designs to help the reader develop an intuitive understanding of optics in the familiar context of eyepieces.
• Written by a Professor of Astrophysics with experience as both an amateur and professional observational astronomer using telescopes at observatories around the world.

Sean G. Ryan is a professional astronomer with almost fifty years’ experience as an amateur observer. He was appointed Professor of Astrophysics at the University of Hertfordshire in 2006, where he was Head and Dean of the School of Physics, Astronomy and Mathematics for ten years. He has published over 100 research papers on observational astronomy, and has co-authored several textbooks, including Visual Astronomy with a Small Telescope.