Lumerical Fdtd Tutorial [top] (ORIGINAL – Guide)

Through step-by-step exercises, the tutorial demonstrates how setting the mesh size ($\Delta x$) relative to the wavelength ($\lambda$) directly impacts accuracy. A key takeaway is the rule of thumb that a mesh of $\lambda/(10-20)$ is required for qualitative results, while plasmonic or high-index contrast structures demand far finer resolution. This reinforces the concept that FDTD is not an automatic solver but a tool requiring deliberate numerical parameterization.