This interface is illuminated at normal incidence from the region [x.sub.3] > [zeta]([x.sub.1]) by a p- or s-polarized broadband Gaussian beam of light of angular frequency [omega], whose plane of incidence
is the [x.sub.1][x.sub.3] plane.
The plane of incidence
is the y-z plane, and the incident angle is defined by the angle between the z-axis and the wave vector k.
"polarized at right angles to the plane of incidence
and strike the bounding surface at the angle of polarization" [5, [section] 37].
The WH formulation is simple and provides insight on how the plane of incidence
affects the current distribution in the LE-PL-OWG FSS.
Let the Cartesian coordinate system be chosen such that z axis coincides with the axis of spheroid, z be equal to 0 in its center, and the plane of incidence
coincides with the plane y = 0.
By [w.sup.E] we denote the component of beam w transverse electric polarized (TE)--its electric field is perpendicular to the plane of incidence
, and by [w.sup.H], the component of beam w transverse magnetic polarized (TM)--its magnetic field is perpendicular to the plane of incidence
When the scratch is oriented horizontally, the reflections from the scratch contours are rotated off the plane of incidence
and are absent in the measurement at all angles (Fig.
Because SE measures the phase shift between light that is polarized parallel and perpendicular to the plane of incidence
, it can be used to measure retardance when the ellipsometer and sample are correctly oriented.
Here, parallel polarization means that vector E is parallel to the plane of incidence
. Consequently, perpendicular polarization means that the direction of vector E is perpendicular to the plane of incidence
For reflection, the incident light wave is resolved into components in the plane of incidence
and normal to the plane of incidence
(the plane of the surface).
When the linearly polarized light interacts with the optical surface, there is a shift in phases of both the components parallel and perpendicular to the plane of incidence
. The shift is usually not the same for both components; therefore, the emerging light is elliptically polarized.
For example in the x-z plane of incidence
, the reflection coefficient for the TM (Transverse Magnetic) or p-polarization is