VARIABLE OPTICAL ATTENUATOR AND OPTICAL VARIABLE ATTENUATOR ARRAY

摘要

PROBLEM TO BE SOLVED: To provide a variable optical attenuator in which high-speed drive is possible and which is not affected by the curvature of a reflection mirror and which can reduce time and labor, such as delicate positioning at the time of manufacturing. SOLUTION: The variable optical attenuator is characterized in that components of the attenuator are arranged so that focusing is obtained on the mirror face of the rotary driving mirror 6 by making the distance from the end face of an optical fiber 4 used in common for input and output to a lens 5 roughly twice of the focal distance f of the lens 5 and the distance from the lens 5 to a rotary driving mirror 6 roughly twice of the focal distance f, after light beams emitted from the end face of the optical fiber 4 used in common for input and output are converged on the mirror face of the rotary driving mirror 6 via the lens 5 and the light beams are reflected on the mirror face. When returning the returned light beams to the end face of the optical fiber 4, the coupling efficiency with respect to the optical fiber 4 of the returned light beams in the end face of the optical fiber 4 is varied by rotatively driving the rotary driving mirror 6. COPYRIGHT: (C)2005,JPO&NCIPI