Methods and apparatus are provided for obtaining spatial information about
an object, and for measuring the dielectric constant of an object. They
include placing the object in a cavity and interacting electromagnetic
radiation at a plurality of frequencies with the object to obtain a
corresponding plurality of measured resonant transverse magnetic modes.
They also include using the plurality of measured resonant transverse
magnetic modes to obtain the spatial information for the object, and/or
using the plurality of measured resonant transverse magnetic modes to
obtain the dielectric constant for the object.
