Vectorial shearing interferometer.

The vectorial shearing interferometer is based on the Mach-Zehnder configuration; it incorporates a displacement shearing system composed of a pair of wedge prisms that modify the optical path difference and the tilt of the sheared wave front with respect to that of the reference wave front. Variable shear and tilt can be implemented along any direction by choice of displacements Delta x and Delta y. The number of fringes and their orientation can be controlled with the vectorial shear. Knowledge of the prescribed displacements in the x and the y directions permits one to obtain a phase gradient in any direction.