Simulated interferometric patterns generated by a nearby star-planet system and detected by a rotational shearing interferometer

Simulated interferometric patterns of the wave fronts generated by a star-p lanet system and detected with a rotational shearing interferometer are der ived analytically and presented graphically. They are identical to the patt erns generated solely by a planet because of the insensitivity of the rotat ional shearing interferometer to the detection of a rotationally symmetric wave front. The variable shearing angle is shown to control the number of f ringes and their orientation. For small shearing angles the phase differenc e in the argument of the cosine function reduces to the derivative of the w ave front multiplied by the shearing angle. The analytical expression for t he intensity detected with a rotational shearing interferometer demonstrate s that the rotational shearing interferometer does not see the on-axis star . (C) 1999 Optical Society of America [S0740-3232(99)01607-5].