Analysis of Hartmann or Shack-Hartmann wave fronts, privileged axes of sub-pupils have non zero angle with sub-pupil matrix directions

摘要

Sensibly square or rectangular sub-pupils are arranged in the analysis plane in the form of a two dimensional matrix. The diffraction figure of a sub-pupil has two privileged axes. Each sub-pupil is oriented relative to the directions of the matrix so that the privileged axes for the diffraction figure of a sub-pupil presents a non zero angle with the matrix directions. Hartmann or Shack-Hartmann wave front analyzer including a group of sampling elements arranged in an analysis plane and forming sub-pupils (C) which permit sampling of the incident wave front. It has a diffraction plane in which are analyzed the diffraction marks from different sub-pupils illuminated by the incident wave front. The form of each sub-pupil is such that the associated diffraction figure (FC) presents in the diffraction plane one or more privileged axes (X1,Y1,X2,Y2). The sub-pupils are oriented in the analysis plane so that the privileged axis or axes for the diffraction figure of a sub-pupil are shifted with respect to the privileged axes of the neighboring sub-pupil diffraction figure so as to limit overlap of diffraction figures. The sampling elements are openings of predetermined shape formed in an opaque screen, associated with micro- lenses.