Tomoyuki Yokokawa

Low-loss pure-silica-core fibers and their possible impact on transmission systems

Low-loss optical fibers are now indispensable transmission media for transmission systems. Recently, the ultralow-loss performance for long transmission systems, the water-loss-free performance for wide-band wavelength-division-multiplexing (WDM) systems, the hydrogen-loss-insensitive performance for system reliability, and the bending-loss-insensitive performance for access or indoor applications have attracted much interest. In this regard, pure-silica-core fibers (PSCFs) are suitable, and unprecedented low-loss PSCFs have been successfully fabricated. This paper introduces the recent progress of low-loss PSCFs and their possible impact on transmission systems.

Dispersion compensating fiber with large negative dispersion around -300 ps/km/nm and its application to compact module for dispersion adjustment

Dispersion compensating fibers with a large dispersion around -300 ps/km/nm were successfully realized while keeping a good bending loss performance, and it was tightly installed in a quite small package applicable to precise dispersion adjustment.

Design optimization of dispersion compensating fibers and their packaging techniques

AbstractDesign optimization of dispersion compensating fibers (DCFs) based on the fundamental mode is described considering the packaging technique. Optical performances of the DCF modules are mainly limited by the macro-, micro-bending loss and the polarization mode dispersion that strongly depend on the module structure. Two types of DCF modules are demonstrated as examples. Bobbin-less module structure that mitigates the bending limit is also described.