We describe the fundamental principle of operation of a vectorial shearing
interferometer, featuring variable shear and tilt. They may be implemented
along an arbitrary direction, in our experimental setup, by controlling the
relative angle between a pair of wedge prisms. We show the simulated inter
ferometric patterns of primary aberrations. We compare them with those exhi
bited by spherical and aspherical optical elements obtained experimentally.
The number and orientation of fringes is controllable with the shear direc
tion and its magnitude. The vectorial shearing interferometer is shown to b
e effective in testing optical elements and in aligning optical systems. (C
) 2001 Society of Photo-Optical Instrumentation Engineers.