title: Atmospheric tomography using a fringe pattern in the sodium layer.
abstract: We wish to measure and separate the contribution of atmospheric turbulent layers for multiconjugate adaptive optics. To this end, we propose to create a periodic fringe pattern in the sodium layer and image it with a modified Hartmann sensor. Overlapping sections of the fringes are imaged by a lenslet array onto contiguous areas in a large-format camera. Low-layer turbulence causes an overall shift of the fringe pattern in each lenslet, and high-attitude turbulence results in internal deformations in the pattern. Parallel Fourier analysis permits separation of the atmospheric layers. Two mirrors, one conjugate to a ground layer and the other conjugate to a single high-altitude layer, are shown to widen the field of view significantly compared with existing methods.
authors.forename: Y
authors.initials: Y
authors.lastname: Baharav
authors.forename: E N
authors.initials: EN
authors.lastname: Ribak
authors.forename: J
authors.initials: J
authors.lastname: Shamir