Recovering low spatial frequencies in wavefront sensing based on intensity measurements
نویسندگان
چکیده
منابع مشابه
Recovering low spatial frequencies in wavefront sensing based on intensity measurements
The transport of intensity equation (TIE) offers a convenient method to retrieve the phase of a wave function from maps of the irradiance (images) recorded at different planes along the optic axis of an optical system. However, being a second-order partial differential equation, even for noise-free data a unique solution of the TIE requires boundary conditions to be specified which are generall...
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Abstract. We propose an efficient approximation to the nonlinear phase diversity method for wavefront reconstruction from intensity measurements. The new method, iterative linear phase diversity (ILPD), assumes that the residual phase aberration is small and makes use of a first order Taylor expansion of the point spread function (PSF) performed for an arbitrary (large) diversity in order to op...
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Earth’s atmospheric turbulence induces aberrations in the wavefront of the optical signal from a distant spacecraft. These aberrations cause diffusion and spreading of the signal energy in the receiver’s focal plane, potentially resulting in an increase in bit-error rate (BER) by several orders of magnitude when significant background radiation is present, such as during daytime operation. The ...
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Correlation wave-front sensing can improve Adaptive Optics (AO) system performance in two keys areas. For point-source-based AO systems, Correlation is more accurate, more robust to changing conditions and provides lower noise than a centroiding algorithm. Experimental results from the Lick AO system and the SSHCL laser AO system confirm this. For remote imaging, Correlation enables the use of ...
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ژورنال
عنوان ژورنال: Advanced Structural and Chemical Imaging
سال: 2016
ISSN: 2198-0926
DOI: 10.1186/s40679-016-0017-y