JPS55166604A - Light fixing attenuator - Google Patents

Abstract

PURPOSE: To decrease the recurrence of light and achieve miniaturization by tilting at least one end face of opposing optical fibers at the specified angle, forming a thin film which attenuates light on at least one end face and packing the end part by light-transparent material.

CONSTITUTION: An optical fiber 1 having both end faces intersecting orthogonally in the axial direction at both ends and an optical fiber 6 which is tapered at one end at the specified angle and is formed with a thin film 7 for attenuating light by the specified attenuation amount to the end face, are disposed on the same axis in the hole of a barrel body 8. The transparent adhesive agent of nearly the same refractive index as that of the optical fibers is packed through the hole 12 into the spacing between the opposing ends of the optical fibers 1 and 6 to bond and fix the optical fibers 1 and 6 to the barrel body 8. The angle of inclination of the end face is made more than the angle θ determined by the numerical aperture of the optical fiber 1. Of the light 5 in the optical fiber 1, the reflected light 51' of the light 51 recurs but the reflected rays 53', 54' of the rays 53, 54 go to the outside by passing through the hole 8 and even if they recur, they attenuate because they enter at the angle larger than the numerical aperture. The recurred light decreases further if the end face of the fiber 1 is tapered as well.

COPYRIGHT: (C)1980,JPO&Japio