| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical attenuator which prevents transmission characteristics of a light signal from deteriorating under the influence of mutual interference between core propagation mode light and clad propagation mode light. SOLUTION: A high-refractive-index liquid 109 in a clad propagation mode removal part 108 installed halfway in a front optical fiber 102 is a material which is much higher in refractive index than the clad part 106 of the front optical fiber 102, and the clad propagation mode light which is propagated in the clad part 106 of the front optical fiber 102 through an input end 101 is not reflected totally by their border surface, but transmitted to the side of the high-refractive-index liquid 109 and attenuates, so that the light does not reach a connection point 105. The clad propagation mode light of a rear optical fiber part 104 is also transmitted to the side of the high-refractive-index liquid 109 in the clad propagation mode removal part 108 and attenuates, so that it does not reach a light projection end 103 either. |
