Abstract: A fiber optic coupler has a cylindrical rod protruding along the apex of an angled block. An optical waveguide is mounted to extend around part of the circumferential of the rod. A transparent body is located on the side of the fiber remote from the rod, and the rod and the body are biased together to bend the fiber around the rod surface and to form an intimate contact between the transparent body and the curved part of the fiber. A light input or output device is positioned to direct light at or receive light from the curved fiber part through the transparent body.

Abstract: An optical switch has a reciprocating prism. In one position of the prism, light passes from an input fiber, through a collimating lens, directly to a focussing lens and then into an output fiber. In another prism position, the collimated light is incident on the prism, is deflected by the prism and enters a different focussing lens and output fiber. Coaxially aligned with the lenses are respective precision molded conical recesses which flare outwardly to receive the precision ground conical ends of fiber terminations.

Abstract: An attenuator for an optical fiber has a tapered screw around which the fiber is looped, the fiber engaging within the screw thread. The fiber is held fixed in position by a spring so that as the screw is rotated the radius of curvature of that part of the fiber held against the screw is altered. Light propagating along the fiber is radiated out at the fiber bend, the level of radiation loss depending on the bend radius of curvature. The attentuator elements are mounted within a light-tight box with the fiber terminating at optical connector components mounted within a wall of the housing. The connector components enable rapid insertion of the attenuator into an optical transmission line to provide an accurate reproducible level of attenuation.

Abstract: A passive fiber optic device and optical fiber connected to it are packaged in a solid block of a bismuth containing fusible alloy. The alloy exhibits appreciable expansion on solidification, negligible dimensional change after solidification, and a low thermal expansion coefficient. Coupled with its low melting point and glass wetting ability, the alloy is uniquely adapted for forming a hermetic seal with glass. By molding as a solid block, the packaging operation is rendered simple and rapid.