| 摘要 |
PURPOSE:To prevent the influence of reflected light upon a laser diode and mode conversion due to the axial shift of a beam by coupling end surfaces of the 1st and the 2nd converging rod lenses with an input and an output optical fiber directly and optically. CONSTITUTION:The 1st converging rod lens 34 fixed to a ferrule 33, the 2nd rod lens 45 fixed to a receptacle 44, and an attenuating film 42 are arranged on a light beam path, and the external input and output optical fibers are coupled with end surfaces of the rod lenses 34 and 45 directly and optically. Further, the attenuating film 42 and surfaces of the lenses facing the attenuation film are provided at about 1 deg. to the light beam. The pitch of a plug part 30 to the 1st converging rod lens is expressed by an equation. Thus, the influence of reflected light upon a laser diode and mode conversion due to the axial shift of the beam are prevented. |
