SBIR Phase II: The Interfractor - A New Optical Dispersive Component

This Small Business Innovation Research Phase II project proposes to develop a new type of optical dispersion element that combines a relief grating with appropriately optimized dielectric films to achieve both high dispersion and high efficiency into one diffraction order, independent of polarization. Grating efficiency is critical for wavelength management in modern fiber-optic telecommunication systems that employ dense wave-division-multiplexing (DWDM) transmission. Dynamic gain equalizers, reconfigurable channel blockers, programmable optical add-drop modules, and wavelength-selective switches all require spatial separation of the wavelengths from an input fiber, typically with a diffraction grating, which is also typically the largest source of insertion loss. Further, because the polarization of the optical signal of any particular wavelength within a fiber may change over time, the net power loss through the device must be independent of polarization. It is very difficult to achieve high grating efficiency in both polarizations. The proposed technology achieves this goal with a proprietary combination of diffractive and thin-film interference effects, and can be fabricated to be robust Over the wide temperature range required of DWDM components The proposed use of this optical dispersion element will be to improve the insertion loss in Free-space optical wavelength-management products, such as dynamic gain equalizers and Reconfigurable channel blockers, now being deployed in modern fiber-optic telecommunication Systems. This technology will implement in other products to change in its own wavelength-management products as soon as the product can be manufactured.