VARIABLE OPTICAL ATTENUATOR

摘要

PROBLEM TO BE SOLVED: To provide a small-sized variable optical attenuator which is capable of lessening the dependence of an optical attenuation quantity on wavelengths, achieving the optical attenuation quantity of >=30 dB and withstanding high light input power. SOLUTION: Lenses 7 and 8 and a substrate 9 are arranged between optical fibers 3 and 4 arranged to face each other across spaced intervals so as shown in (a) of Figure 1 and the mode field diameter of the light emitted from the optical fiber 3 is enlarged by the lens 7 and is made into parallel beams which are then propagated to the substrate 9 side. As shown in (b) and (c) of the same figure, the constitution to arrange a light shielding plate 1 on the substrate 9 and to shield at least part of the light propagated between the optical fibers 3 and 4 is adopted and a V-shaped notch 2 is formed at the light shielding end of the light shielding plate 1. The light shielding plate 1 is moved in a direction intersecting with the optical path of the light by the electrostatic force generated by a comb-shaped driving section 6a.