Different-Mode Power Splitters for Optical Testing of Three-Channel and Dual-Mode Waveguide Crossing

Abstract We study that the different-mode (waveguide-connected) power splitter [(W)PS] can provide different-mode testing points for the optical testing. With the PS or WPS providing two different-mode testing points, the measured insertion losses (ILs) of the three-channel and dual-mode waveguide crossing (WC) for both the fundamental transverse electric (TE0) and TE1 modes are less than 1.8 dB or 1.9 dB from 1540 nm to 1560 nm. At the same time, the crosstalks (CTs) are lower than −17.4 dB or −18.2 dB. The consistent test results indicate the accuracy of the (W)PS-based testing circuit. Additionally, combining the tunable tap couplers, the (W)PS can provide multiple testing points with different modes and different transmittances.