In its third edition theory and practice of optics and refraction constitutes a part of modern system of ophthalmology (mso) series. Without altering the basic text and layout, each chapter in this edition has been thoroughly revised to keep abreast with newer concepts and principles of optics and refraction involved in investigative as well as treatment modalities evolved over the period of time.key features: intends to provide information on basic principles of optics and refraction to the residents in ophthalmology as well as students of optometry and orthopedics. Organizes text in attractive four-color format to make understanding, retention and reproducibility of facts easy. Includes newer concepts in refractive surgery like all femtosecond laser surgery (relex) and corneal inlay for presbyopia. Incorporates topics on advances in aberrometry, wavefront technology, anterior segment optical coherence tomography (as-oct), confocal microscopy of cornea and anterior segment ultrasound bio microscopy. Comprises chapter on clinical refraction refurbished effectively and text on corneal topography expanded with essential newer developments.