Grating Coupler · 1550 nm

This grating coupler is designed for fiber-to-chip coupling on a silicon nitride (SiN) platform, optimized to maximize efficiency at a 1550 nm operating wavelength. The analytic estimate predicts a transmission efficiency of 30.1%, equivalently an insertion loss of 5.217 dB (the same transmission expressed two ways), over a 40.0 nm bandwidth. The design uses a 29-period grating with a 1.1155 µm period and 0.55 fill factor on a 1 µm waveguide width, with a 100 µm bend radius, occupying a footprint of 183.35 × 13 µm. It achieves a strong fabrication score of 99.0/100, indicating high manufacturability. These figures reflect analytic estimates rather than a full physical simulation.