Abstract: A transverse load sensitive optical treadle switch. The switch includes a deformable longitudinal housing and a fiber optic assembly positioned within the housing. The fiber optic assembly includes an optical fiber having a first end and a second end, the optical fiber being subject to bending upon application of a transverse load to said housing. Means for mounting the optical fiber in the housing so as to permit bending of the fiber in response to application of a transverse load to said housing are provided, the degree of bending being sufficient to cause a significant decrease in passage of light through said fiber when said fiber is bent. Means permitting introduction of light into said optical fiber at the first end of the optical fiber and means for permitting the exit of light from the second end are also provided.

Abstract: Means for coupling an electrooptical device, such as a semiconductor laser, to an optical fiber avoids heat-induced stresses that commonly result from joining methods employing welding, soldering, or catalytic adhesive compositions. In this invention, the electrooptical device and fiber are firmly mounted within separate elements, such as copper tubes, by means of potting compound or the like, and after close end-to-end supported alignment of the device and fiber elements to obtain optimum light coupling, the assemblage is immersed in an electrolytic plating solution. Plating current is then applied and maintained until a sufficiently strong layer of plating metal encompasses the tubular elements and thereby rigidly fixes the alignment of the device and fiber end at its optimum position. Since the plating operation proceeds in a substantially isothermic environment, there is no misaligning stress introduced which would otherwise degrade the coupling efficiency.

Abstract: A method for manufacturing a fiber type coupler or the present invention by fusing and elongating a plurality of optical fibers is characterized in that a multi-wire optical fiber wire is used as the plurality of optical fibers.

Abstract: A fiber optic coupler of the type wherein first and second single-mode optical fibers, each having a core and a cladding, are fused together along a portion of the lengths thereof to form a coupling region. The fiber diameters are smaller in the coupling region than in the remainder of the fibers. The cladding of the second fiber contains an amount of chlorine sufficient to increase the refractive index n.sub.2 ' thereof to a value greater than the refractive index n.sub.2 of the cladding of the first fiber.