Summary — Lesson 5

The FDTD solver region is used to specify simulation settings including:

• Maximum simulation time
• Position and size of the simulated region
• Simulation mesh
• Boundary conditions

Mesh types available are:

• Auto non-uniform (default): This uses the mesh accuracy setting to generate a graded (non-uniform) mesh based on a target number of mesh points per wavelength
• Custom non-uniform: Generates a graded (non-uniform) mesh if you specify a target number of mesh points per wavelength or combination of mesh cells per wavelength and maximum mesh step size. Generates a uniform mesh if you specify a maximum mesh step size or number of mesh cells in each direction
• Uniform: Generates a uniform mesh based on either the maximum mesh step size or number of mesh cells in each direction

Mesh override regions can be used in conjunction with non-uniform mesh types to specify a finer mesh where needed

The simulation mesh can be viewed by using the “View simulation mesh” button in the View toolbar

Boundary conditions available include:

• PML
• Metal
• Periodic
• Symmetric
• Anti-symmetric
• Bloch
• PMC

Advanced options include setting the simulation bandwidth used for mesh generation, material fitting, and monitor data collection, and using the early shut-off feature to end the simulation once the fraction of energy remaining in the simulation falls below a specified threshold value.