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Updated: Jun 12, 2026

Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating
Published on: October 11, 2016
Variable phase grating optical aberrator
Abstract:
We have developed and analyzed a heated laminar airflow device which introduces easily varied aberrations into optical beam trains. The aberrator produced nearly sinusoidal optical path differences of modulation depth 0 to 2lambda (peak to valley) at a 355-nm wavelength and a spatial frequency of ~2 cycles/cm. The phase modulation was measured via lateral shearing interferometry and agreed with a sinusoidal near field phase model to ~10%. The far field intensity profile was in qualitative agreement with the theory of focused sinusoidal phase gratings.
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