| 摘要 |
PURPOSE:To provide the optical attenuator which can easily be set to a necessary optical attenuation quantity. CONSTITUTION:The input light OPTin of the optical attenuator passes through a light branching unit HM 1 and is attenuated by an optical attenuation medium OAT 2 as specified and then outputted as light OPTout. Part OPT 1 of the input light OPTin is converted by a photodetector DET 4 into an electric signal and the transmitted light OPT 3 of the optical attenuation medium OAT 2 is converted by a photogetector DET 5 into an electric signal. A comparing circuit DIF 6 calculates the optical attenuation quantity of the optical attenuation medium OAT 2 according to those electric signals and displays it on a display unit DSP 7. |
