
This taper gives rise to the flattened spectral response of each channel, which can
be seen in Figure 20.4, along with a magnified view of a single channel with both
flattened and un-flattened responses. Precise simulation of this taper is critical for
accurate prediction of this device’s spectral performance, which is important due
to the trade-off between flatness and crosstalk.
The Finite-Difference Time-Domain (FDTD) Method
This section describes the well-known finite-difference time-domain (FDTD)
technique [4, 5]. The FDTD method is a rigorous solution to Maxwell’s equations
and does not have any approximations or theoretical restrictions. This ...