Abstract: A polarization-mode selective semiconductor laser includes a semiconductor laser structure including an active layer for generating gain spectra for the first and second different polarization modes and a diffraction grating formed with a uniform pitch over the laser structure. The laser structure includes a first DFB reflector portion with a first channel stripe and a second DFB reflector portion with a second channel stripe connected to the first stripe channel. The first DFB reflector portion and the second DFB reflector portion is serially arranged in a cavity direction of the laser.

Abstract: A process and apparatus for marking an outer jacket of an S-Z stranded cable to indicate the locations of switchbacks thereunder. The process comprises passing a portion of a cable core within a field of view of an imaging means to acquire an image thereof. The quantity of visually distinguishable conductors in the acquired image is compared to a reference value. If the reference value is exceeded, a transition region or switchback is indicated. Once a transition region is indicated, its position is tracked through a outer jacketing step. A marking to indication the location of the transition region is applied to the outer jacket according to the tracked position of the transition region.