Effective index monitors records the effective index values as a function of frequency/wavelength in a varFDTD simulation. The geometry of effective index monitors is restricted to 2D z-normal.
Override global monitor settings
A toggle to override the global monitor settings. If checked, the user can specify the frequency range and number of points at which frequency-domain information will be recorded (using the options described below). If unchecked the options below are set from the global monitor settings.
- USE LINEAR WAVELENGTH SPACING: By default, data is recorded at linearly spaced points with respect to frequency. Selecting this option spaces data at linearly spaced points with respect to wavelength.
- USE SOURCE LIMITS: When checked these monitors use the source limits. When unchecked, the frequencies/wavelengths at which to record data can be set using the pull down menus and boxes below them.
- FREQUENCY POINTS: Set to choose the number of frequency points at which to record data.
- SET GLOBAL MONITOR SETTINGS: Access to global properties
Monitor type: The monitor type and orientation, this option will control the available of spatial setting below
- X, Y, Z: The center position of the simulation region
- X MIN, X MAX: X min, X max position
- Y MIN, Y MAX: Y min, Y max position
- Z MIN, Z MAX: Z min, Z max position
- X SPAN, Y SPAN, Z SPAN: X, Y, Z span of the simulation region
The DOWN SAMPLE X, Y, Z option is used to set the spatial downsampling performed by the monitor. A down sample value of N corresponds to sampling (recording) the data every Nth grid points. Setting the down sample value to 1 gives the most detailed spatial information (i.e. information at each grid point).
Note: This tab includes options which should only be changed if you are quite familiar with the meshing algorithm and techniques used.
- SPATIAL INTERPOLATION: There are three options for index monitors. The default option, SPECIFIED POSITION returns the index that that the field sees at the location where the monitor is placed. The next two options. NEAREST MESH CELL and NONE are as described for time-domain monitors. In simulations with mesh refinement turned on, the default option does not show the averaging of the indices, but the other options do.
- RECORD DATA WITHIN PML: This option is as described above for time domain monitors.
- RECORD CONFORMAL MESH WHEN POSSIBLE: Enabled by default. The index monitor will record the the effect of the conformal mesh. It is helpful to disable this option when doing absorption calculations.