This fifth volume of the series Lectures in Optics provides comprehensive coverage of ocular imaging, a broad field comprising diagnostic instrumentation that assists in the production of biometric data as well as two- and three-dimensional images of the eye. Aided by developments in digital imaging and computer processing, ocular imaging has seen explosive growth that has transformed ocular care into a very precise and accurate field, assisting in the diagnosis of several diseases as well as the management, planning, and postoperative follow up of several refractive surgical procedures, such as laser corneal refractive correction of ametropia and cataract surgery / IOL implantation. The field of ocular imaging is so broad that no book can possibly cover it in its entirety. This book emphasizes the refractive aspect of imaging. It starts by discussing the diagnostics (ultrasound and optical) that focus on the anterior segment of the eye. Then, technologies such as Scheimpflug, slit scan, optical coherence tomography, Placido, and color-coded elevation topography are presented with applications such as pachymetry and the accurate measurement of corneal curvature, shape, and biomechanics. Yet another field of imaging is aberration measurement, or aberrometry, which evaluates the optical system of the eye in its entirety and therefore warrants significant attention, as is reflected in the book. Finally, applications of ocular imaging are presented alongside their ultimate application-surgical procedures for correcting refractive error of the eye.