| 摘要 |
PROBLEM TO BE SOLVED: To obtain the small-sized optical attenuator which is free of variation in-attenuation quantity due to changes of use environment and wire breaking due to secular changes of an optical fiber and by which its attenuation quantity can be optionally adjusted. SOLUTION: The optical fiber 5 structured by surrounding at least an optical fiber core 3 with an optical fiber clad 4 is inserted and fixed, the polished end surfaces 8 of two ferrules 1 are put in a sleeve 9 while made to abut against each other, and one or both of the ferrules 1 are rotated to change the relative positions of the axes of optical fiber core 3, thereby adjusting the connection loss at the abutting part of the ferrules 1. In this case, the hole diameter R1 of the ferrules 1 is made large and the external diameter R2 of optical fibers 5 is made smaller than the hole diameter R1 of the ferrules 1 so that variation of the relative positions of the axes of the optical fiber cores 3 due to the rotation of the ferrules 1 becomes small. |
