Abstract: An optical system is provided for coupling light from one optical waveguide to another. By offsetting the parallel optical axes of two GRIN lenses by a minimum of 50 .mu.m there is a significant reduction in unwanted effects from reflections. Furthermore etalon effects present in many optical coupling systems having parallel inwardly facing end-faces are reduced. The invention obviates the costly solution of for slanting one of the inwardly end-faces of the lens.

Abstract: An optical demultiplexor utilizes a single optical interference filter disposed between an input end and an output end of the device. The filter is preferably housed within a cavity in a glass block having an upstanding input end, endwall. The optical filter is a wavelength selective means having a wavelength characteristic dependent upon an angle of incidence. The device has a plurality of reflective surfaces disposed at the input end for reflecting light reflected from the filter, back to the filter at different predetermined angles. Each different predetermined incident angle allows a different predetermined wavelength of light to pass through the filter to an output end being spatially separated from other predetermined wavelengths that pass through the filter. The reflective surfaces are preferably formed in the upstanding endwall of the glass block. Sixteen channels can be separated by this demultiplexor.

Abstract: A method and device is provided wherein a reinforcement is provided for one or more optical fibers. One or more fibers are inserted into a sleeve made of a material that is substantially the same as the material of the cladding of the one or more optical fibers. The bore of the sleeve is sized to accommodate the one or more optical fibers; After the one or more optical fibers is inserted into the sleeve sufficient heat is applied to the sleeve for a duration to collapse the sleeve onto the one or more optical fibers. Preferably, the sleeve is a glass pre-form consisting substantially of 90% or greater silica.