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Hydrodynamics of the turbulent point-spread function
Journal of the Optical Society of America A, 2013We derive hydrodynamic equations for the point-spread function of an imaging system looking through atmospheric turbulence at an incoherent object. These are derived from the hydrodynamics of the index of refraction of the air. We use the path integral representation of the paraxial approximation for wave propagation through turbulence.
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Effective Point Spread Function
2015Image modeling based on the Monte Carlo method is time consuming because a large number of incident photons are required to ensure a required accuracy. The requiring of computational time increases significantly when images of complicated objects embedded in a turbid medium are modeled. To address this problem, the concept of the effective point spread
Min Gu, Xiaosong Gan, Xiaoyuan Deng
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Blind Deconvolution for Symmetric Point-spread Functions
2005 IEEE Engineering in Medicine and Biology 27th Annual Conference, 2005Blind deconvolution is to restore a blurred image without full information of the associated point-spread function (PSF). One recent method is to formulate an equation with only the image as unknowns by eliminating the PSF because of its symmetric property. The original image is then recovered by solving the latter equation.
Yifei, Lou +3 more
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On point spread function modelling
2012Point spread function (PSF) modelling is a central part of any astronomy data analysis relying on measuring the shapes of objects. It is especially crucial for weak gravitational lensing, in order to beat down systematics and allow one to reach the full potential of weak lensing in measuring dark energy.
Bergé, Joel +3 more
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Point Spread Function Estimation for Neutron Images
Proceedings of the 2019 2nd International Conference on Electronics and Electrical Engineering Technology, 2019The neutron images produced by small power reactor like TRIGA MARK II PUSPATI research reactor (RTP) are inherently blurred due to low length-to-diameter ratio (L/D) at the neutron radiography facility. Hence, restoration is commonly undertaken in order to improve the visual quality of these image.
Khairiah Yazid, Mohd Zaid Abdullah
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Dielectric metalenses with engineered point spread function
Applied Optics, 2017High-index silicon nanoblocks support excitation of both electric and magnetic resonance modes at telecommunication wavelengths. At frequencies where both electric and magnetic resonance modes are excited simultaneously, changing the geometrical dimensions of the silicon cubes creates a 2π full span over the phase of the transmitted light in different ...
Mohammad Mahdi, Shanei +3 more
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Point Spread Function Optimization for MRI Reconstruction
Proceedings. (ICASSP '05). IEEE International Conference on Acoustics, Speech, and Signal Processing, 2005., 2006Magnetic resonance imaging (MRI) requires reconstruction of an image from non-uniformly sampled Fourier domain data. The point spread function (PSF) is strongly affected by the Fourier weights, also called density compensation function (DCF). We formulate the DCF selection as an optimization problem with linear matrix inequality (LMI) constraints.
Hao Tan, Yibin Zheng
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The Telescope Point Spread Function
Publications of the Astronomical Society of the Pacific, 1996New observations are used to accurately define the stellar point spread function produced by atmospheric turbulence at the focus of large telescopes and to compare its profile to those computed from wavefronts characterized by various structure functions.
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Scalar and Electromagnetic Diffraction Point-Spread Functions
Applied Optics, 1998We describe an accurate technique for computing the diffraction point-spread function for optical systems. The approach is based on the combined method of ray tracing and diffraction, which implies that the computation is accomplished in a two-step procedure.
J J, Stamnes, H, Heier
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Optimization of point spread function in ultrasound arrays
Ultrasonics, 2006The design of aperture weightings in ultrasound arrays is a multi-objective optimization problem, involving parameters such as delays, aperture size, focal depth, operating frequency and beam properties. Besides, apodization causes the SNR in array output to be decreased.
M, Sakhaei, A, Mahloojifar, A, Malek
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