OPTICAL DISPERSION COMPENSATION ELEMENT

摘要

PROBLEM TO BE SOLVED: To solve the problem that a sufficient countermeasure for third order wavelength dispersion compensation is not yet proposed, although the third or higher order wavelength dispersion compensation is still estimated to become necessary because accurate communication is hardly attained with the conventional method of wavelength dispersion compensation due to an accelerated communication bit rate and a lengthened communication distance in an optical communication system using an optical fiber. SOLUTION: The third order dispersion is completely compensated by forming an optical dispersion compensation element using a multilayer film formed of a first reflection layer, a first light-transmissive layer, a second reflection layer, a second light-transmissive layer and a third reflection layer successively with combination of a high refractive index layer (layer H) and a low refractive index layer (layer L). Then by constructing the multilayer film so as to make the film thickness very in directions in the incident plane, the optical dispersion compensation element capable of the third order dispersion compensation with respect to various incident light is manufactured. Insertion loss is suppressed to be <=0.5 dB.