Optical signal with multilayer integrated optical fan-out devices

In the field of active phased array applications, the needs for high frequency carriers and very wideband communication and radar Systems technologies with low volume, e.g. for airborne applications, drives the development of new concepts for all components of such networks. One building block for the beamforming in active antennas is the summation of signals, coming from different modules of the network. This paper presents the realization of an optical summation via integrated optical fan-out devices consisting of four stacked layers of single-mode waveguides. A novel fabrication method for these all-polymer multilayer devices is developed. This new process scheme as well as experimental results from the characterization of two exemplary versions of fan-outs (with and without equal path lengths)are discussed in detail.