Dispersion-Enhanced Multiplexed Photopolymer Graft for Multiwavelength Distributed Optical Interconnection Networks

To further enhance the bandwidth promised by optics, wavelength division multiplexing (WDM) scheme is becoming one of the major thrusts in photonics research. Most of the WDMs demonstrated are made out of glass and III-V compound semiconductor. The non-multiplexibility and the small index modulation of these inorganic materials result in severe restrictions that make WDM systems incapable of handling such needed functions as l-to-many fanout at the same WDM node, surface normal packaging to increase reliabilitv. and two-dimensional fanout flexibility. Radiant Research, Inc., (RRI), proposes a dispersion-enhanced multiplexed photopolymer graft for multiwavelength distribution networks. The basic material research is aimed at providing all the needed features that can not be achieved through employing glass and III-V compound semiconductor. High density WDM and l-to-many fanouts will be demonstrated using the dispersion-enhanced multiplexed photopolvmer graft. In contrast to the existing WDMs that have a surface-relief grating pattern due to the small intrinsic index modulation, the photopolymer films have an index modulation as large as 0.2. As a result, tilted grating profiles with high spatial resolutions can be made for surface-normal fanouts that is able to achieve a 2D fanout structure, realizing the full advantages of optics, that is not achievable through conventional approaches. A critical product that can be generated out of this program is the high spatial resolution multiplexed gratings for WDM system integration. The gratings to be fabricated in this program has a myriad of applications other than the proposed one. The photopolymer employed is transparent from 400 nm to 1.6 mm. Therefore, the 2D WDM-fanout device can be used for almost any interconnection network using visible and near IR as the signal carriers. Further applications such as bit-parallel optical interconnects (developed at JPL), optical sensors, optical spectrum analyzers, and ground-to-satellite and satellite-to-satellite laser communications are all feasible.