Patent ID: 7336359

Claim:
A method for measuring a property associated with a sample comprising the steps of: projecting an incident polarized light beam having at least one polarization state through a total internal reflection cell containing said sample to generate an exigent light beam having a complex polarization; projecting said exigent light beam through an exigent light beam path comprising a quarter wave plate having a quarter wave plate rotation angle and half wave plate having a half wave plate rotation angle, and a first detector operable to produce a detected signal intensity; iteratively adjusting said quarter wave plate rotation angle and said half wave plate rotation angle to produce a minimum detected signal intensity at said first detector for at least one of said selectable polarization states; determining ellipsometric nulling angles from said quarter wave plate rotation angle and said half wave plate rotation angle at said minimum detected signal intensity; and using said ellipsometric nulling angles to provide an indication of said complex polarization of said exigent light beam; wherein said complex polarization of said exigent light beam provides an indication of said property associated with said sample.