| 摘要 |
PURPOSE:To obtain optical fixed attenuators which have various attenuation quantities by providing a 1st optical fiber which has an end surface slanting to the optical axis, a 2nd optical fiber which has a slanting end surface opposite said slanting end surface, and attenuation films provides to those two slanting end surfaces, and bringing those two slanting end surfaces into contact with each other. CONSTITUTION:Plural capillaries which are made uniform in external diameter, hole diameter, concentricity, finished state, etc., with high accuracy are prepared and optical fibers 7 of the same kind are run through the holes of the two capillaries 6 and fixed by adhesion. Then the end surface of one side where the optical fiber 7 projects is polished together with the capillary 6 to form the slanting surface having a certain constant tilt angle to the center axis of the optical fiber 7, and the other end surface is polished into a plane at right angles. Then attenuation films are vapor-deposited over the entire slanting end surfaces, which are made to abut on each other and adhered while the optical axes are aligned with each other. When the attenuation films 10 are vapor-deposited, four kinds of capillaries 6 which have, for example, 0-3dB attenuation quantities are formed and combined to obtain six kinds of attenuation quantities, i.e. 1-6dB. Consequently, optical fixed attenuators having various attenuation quantities are easily manufactured. |
