For a fiber reinforced plastic composites, the advantage of high strength and high stiffness of fibers, the original physical and chemical identities of matrix, together the high mechanical properties of composite material can only be achieved with a strong interface. This book tells a novel and non-destructive method of analyze the interface between carbon fiber and epoxy resin by using Raman spectroscopy, in a micro-mechanical manner. It will give a new perspective to observe and analyze the changes of the interface under different stress conditions.