Syntax: D <file> <outperm> <inperm> <xoffset> <yoffset> <xref> <yref> [-]
The 'D' element at the beginning of a line defines a dielectric. The geometry of the dielectric contour is further specified in the file <file>
. The dielectric contour is intended as the interface between two regions with relative permettivities <outperm>
and <inperm>
. The relative permittivities <outperm>
and <inperm>
can be complex valued, in the format eRe-jeIm, where eRe is the real part of the complex permittivity value, and eIm is the imaginary part. The dielectric can be translated with respect to the coordinates defined in <file>
by an offset (xoffset, yoffset), thus allowing to reuse the same geometric definitions multiple times. The reference point (xref, yref) and the optional -
argument are used to specify which side of the dielectric interface has which permittivity. More specifically, the reference point is assumed to lie on the <outperm>
side of all the segments in <file>
. The optional -
argument indicates that (xref, yref) instead lies on the <inperm>
side. The reference point is not translated, i.e. the offset only applies to the elements specified in <file>
.
Remark: it is the user's responsibility to make sure that the reference point is on the same side of the dielectric interface for all panels. That is, each panel is evaluated as stand-alone with respect to the reference point, to define its <outperm>
and <inperm>
sides. There is no concept of a external and internal side of a surface specified by a group of panels, even if specified in the same file with the same conductor names, since FasterCap maintains no topological information.
Example 1:
D circle_0.15_fine.txt 1.0 2.0 0.0 0.0 0.0 0.0 -
This input file fragments specifies a dielectric interface whose geometry is defined in the file circle_0.15_fine.txt. The interior of the circle is filled with a material with relative permittivity equal to 2.0, since the reference point is centered on the origin and the optional -
argument is specified; while the dielectric medium ouside the circle has a relative permittivity equal to 1.0.
Example 2:
D circle_0.15_fine.txt 3.0-j0.02 1.0 0.0 0.0 0.0 0.0 -
This input file fragments specifies a dielectric interface whose geometry is defined in the file circle_0.15_fine.txt. The interface is between air (relative permittivity equal to 1.0) and a lossy dielectric with complex relative permettivity equal to 3.0-j0.02 (e.g. with real part equal to 3.0 and imaginary part equal to 0.02).