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Updated: Jun 14, 2026

Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating
Published on: October 11, 2016
Complex spatial coherence function: its measurement by means of a phase-modulated shearing interferometer
Abstract:
A stellar interferometer is proposed that has the following characteristics: parallel shear, phase modulation and detection, white light fringes, simplicity, and high mechanical stability. The interferometer developed is able to measure the complex coherence function of a star and distinguish it from most telescopic and atmospheric aberrations. This is achieved by detection of the fringes in the exit pupil, which is divided into small areas each less than a projected atmospheric isoplanatic patch. Then the phase-modulated fringes are detected independently in each area and summed incoherently. A description of a laboratory simulation is given.
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