The field region object is a source and monitor combination, combining the functionality of a frequency-domain monitor and a volumetric current source.
Currently, this object is only used as an input object for the lumopt function for optimizations. While settings are available in the object, the object is not intended to be used alone.
For more information on usage for the field region object for optimization problem, see the Application Gallery article on Inverse Design of Metasurface Color Router and the Knowledge Base article on Getting Started with lumopt.
General Tab
The left side of the general tab is used to set properties of the field region source as a monitor, whereas the right side of the general tab is used to set properties of the field region object as a source, which is automatically invoked during different steps of the operation.
Monitor Settings (Left)
Note: While the field region object supports the selection of a wavelength/frequency range, the monitor will only use the center wavelength/frequency for its calculations.
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.
SAMPLE SPACING: This combo-choice parameter determines how the sample frequency/wavelength will be selected. The three sample options are "uniform", "chebyshev" and "custom".
- USE WAVELENGTH SPACING: By default, data is recorded at certain spaced points with respect to frequency. Selecting this option spaces data at certain 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.
When sample spacing is selected to be "custom", all the above settings will be disabled and a "custom frequency samples" table will be shown. Properties of the table are:
- ADD: Adds an entry above the selected entry to the "frequency (THz)" table
- REMOVE: Removes the selected entry from the "frequency (THz)" table
- SORT: Sorts the table with frequency from low to high
- set global monitor settings: Access to global properties
Source Settings (Right)
SOURCE MODE: Toggle whether the object is used as a source or a monitor. This is automatically adjusted during the optimization process and should not be manually changed.
NUTTALL WINDOW PULSE: Toggle whether a Nuttall window is used for the current source pulse.
Geometry Tab
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
Results Returned
This object is only meant to be used with the lumopt procedure, therefore, the results returned by this object in the CAD window should not be used independently in the current version.