Optical communications offer another means, in addition to the more traditional broadcast and electrical methods, of transmitting information. In optical communications a light beam from a laser or light emitting diode is modulated and transmitted along an optical fiber between sending and receiving points. It is important that the light travel along the optical fiber and not be lost by transmission through the walls. Therefore, commercially available optical fibers comprise a glass fiber core and a surrounding cladding, each having differences in refractive index such that the light is retained within the optical fiber. Fused silica and other glasses are often employed as the host materials both for the core and the cladding. Fibers employing these materials are thin, fragile and difficult to handle. As a result, the cladding is covered with protective polymeric layers to increase handleability and prevent unwanted fracturing of the optical fiber. In some optical fibers the cladding is surrounded by a polysiloxane layer which in turn is coated with a layer of a polyester such a polyethylene terephthalate.
When the optical fiber is connected to a light source or is to be coupled to another fiber, the protective polymeric layers must be removed. The traditional method of mechanically stripping the outer polymeric layers is unsatisfactory because it requires special skill, leads to breakage of the fiber and is, in addition, time consuming. The use of organic solvents to strip the polymeric layers leads to environmental, health and flammability problems. It would therefore be desirable to develop a method of chemically removing the protective layers without damaging the inner core and cladding which avoids the use of organic solvents. More than one reagent may be required to chemically strip the layers when the protective layers are made of different polymeric materials having different chemical properties.
USPTO Backgrounds
USPTO Backgrounds