Ronald C Weiss

US Patent:

48529648, Aug 1, 1989

Filed:

Mar 4, 1987

Appl. No.:

7/021467

Inventors:

John W. Holland - Countryside IL
Ronald J. Weiss - Addison IL

Assignee:

Storm Products Co. - Hinsdale IL

International Classification:

G02B 644

US Classification:

350 9623

Abstract:

A coiled fiber optic cable comprises an optical fiber of glass or plastic that is disposed loosely within a buffer tube. The buffer tube in turn is surrounded with a plastic strength member that is then jacketed in a thermoplastic cover. The assembled cable is wound on a mandrel in a closed helix and is heated to set the helical shape in the plastic member. After cooling, the spiral may be reverse wound to set the coiled configuration. The optical fiber may be single-mode or multimode and it may be graded-index clad or step-index clad. The coiled cable can be terminated to interconnect optical components. If the optical fiber is a single-mode fiber that is not treated to reduce internal reflections when it is bent, then the attenuation of the optical signal will be found to be an inverse function of the extension of the coiled cable. This makes it possible to use coiled single-mode fiber as an optical attenuator in a mechanical apparatus that supports the coiled fiber and provides repeatable positioning to obtain a predetermined value of optical attenuation.