| 摘要 |
PROBLEM TO BE SOLVED: To improve a mounting property of a variable optical attenuator and to easily and precisely adjust the amount of optical attenuation. SOLUTION: This variable optical attenuator is provided with a first optical fiber 11, a reflection mirror 31 which reflects a light beam emitted from the end face of the first optical fiber 11, a second optical fiber 12 which is arranged in parallel with the first optical fiber 11 and in which an outgoing light beam reflected by the reflection mirror 31 is made incident and a position adjusting section which adjusts the distance between the reflection mirror 31 and the end face of the first optical fiber 11. Moreover, in the constitution mentioned above a beam focusing lens 21, which is arranged between the end face and the reflection mirror 31, is provided to focus the light beam emitted from the end face. The position adjusting section is provided with a cylinder 41 which houses the reflection mirror 31 and has a thread on its outside diameter section and a casing 51 which houses the first optical fiber 11 and the second optical fiber 12 and has a thread on its inside diameter section to engage the cylinder 41. The distance is adjusted by rotating the cylinder 41. |
