Transmission two-modulator generalized ellipsometry measurements.

The two-modulator generalized ellipsometer has been used to measure samples in transmission. In this configuration, the instrument can completely characterize a linear diattenuator and retarder, measuring birefringence, diattenuation, the angle of the principal axis, and the sample depolarization simultaneously and accurately. This instrument can be operated in two modes: (1) spectroscopic, in which measurements are made through the entire sample aperture as a function of wavelength, and (2) spatially resolved, in which measurements are made at a single wavelength and a birefringence picture is made of the sample. Current spatially resolved measurements have been made at a resolution of approximately 40 microm. Four samples have been examined with this instrument: (1) a mica plate, (2) a Polaroid polarizer, and (3) two quartz plates.