This book, Applied Optics, is a fundamental technical coursefor the specialties of optical engineering, optical measurement,control instruments and electronic science and technology. The bookmainly includes basictheories and methods of how to solve problemsof geometrical optics, typicaloptical instruments, opticalmeasurement, color measurement, optical fibersystems, laser systemsand infrared optics. The knowledge mentioned aboveis a must for theopto-electronic students' learning.