Quadrature phase-shifting interferometer using a polarization prism

A new type of a phase-shifting interferometer is presented, where two fringe patterns in quadrature are simultaneously formed on an image sensor plane using a 1/8 wave plate and a polarization prism. The quadrature phaseshifting fringe patterns are acquired in each state plane of the interferometer. The phase calculation method with these four fringes patterns gives two phase distributions which are phase sum and difference between two states of the interferometer. Two interferometric systems will be presented, one of which uses one illuminating light and mechanically moving parts of the interferometer, and the other utilizes two illuminating light with different wavelengths. We will present the principles of the methods and some experimental verifications will be also given.