Rotationally shearing interferometer for extra-solar planet detection: preliminary results with a solar system simulator

We describe preliminary experimental results on the laboratory demonstration of a technique to detect an extrasolar planet using a rotationally shearing interferometer. We simulate a planet and a star in a laboratory solar system. It consists of two laser beams; each passed through a spatial filter, collimated and combined. We confirm the theoretical prediction that the on-axis star generates no fringes for any shear angle. The star generates a uniform wave front that is invariant to the shear angle. Additionally, we demonstrate that the off-axis planet produces straight fringes. Thus, the mere presence of fringes confirms the existence of a planet. Furthermore, we illustrate that the fringe density and their inclination increase with the shear angle in the rotational shearing interferometer. Therefore, the number of fringes and their direction may be changed from the Earth to confirm (or reject) the existence of a planet. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement