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The conventional Broyden-Fletcher-Goldfarb-Shanno (BFGS) method used to solve the cost function of a phase diversity (PD) algorithm converges to a global optimum only when the cost function is convex. We present a modified BFGS method, which has fine global convergences for both convex and nonconvex functions, guarantees that the solutions will converge to(More)
We present a color transfer method, which is designed to give fused multiband nighttime imagery a natural daytime color appearance in a simple and efficient way. Instead of using traditional nonlinear l space, the proposed method transfers the color distribution of the target image (daylight color image) to the source image (fused multiband nighttime(More)
The misalignment between recorded in-focus and out-of-focus images using the Phase Diversity (PD) algorithm leads to a dramatic decline in wavefront detection accuracy and image recovery quality for segmented active optics systems. This paper demonstrates the theoretical relationship between the image misalignment and tip-tilt terms in Zernike polynomials(More)
We present a simplified solution to phase diversity when the observed object is a point source. It utilizes an iterative linearization of the point spread function (PSF) at two or more diverse planes by first-order Taylor expansion to reconstruct the initial wavefront. To enhance the influence of the PSF in the defocal plane which is usually very dim(More)
A statically determinate kinematic mount structure is designed for an astronomical observation instrument. The basic principle of the proposed kinematic mount is introduced in detail, including the design principle, its structure, and its degrees of freedom. The compliance equations for the single-axis right circle flexure hinge are deduced, and(More)
A Strategy of Real-Time Adjusting of Yaw Angle (SRTAYA) of space camera was proposed base on General Image-Quality Equation (GIQE). During space camera imaging, yaw angle which is caused by rotation of the earth and the gesture changing of satellite impacts integral aspect of TDI (Time Delay and Integration) CCD (Charge Couple Device), so that the image(More)
In this paper, the Zernike coefficient is analytically expressed as the product of the dependence of aberration field decenter vectors (related with perturbations) and the dependence of fields of view (FOVs), on the frame work of nodal aberration theory (NAT). By expanding and analyzing this expression, an alignment strategy by optical compensation for the(More)
Classic graphplan has too much restriction on capturing the full subtlety of many real problems. Flexible graphplan is defined which supports the soft constraints often found in reality. Heuristic concept is introduced to the process of plan extraction in flexible graphplan in order to improve the efficiency of plan extraction and the quality of plan. A(More)
Our paper mainly separates the specific aberration contributions of third-order astigmatism and third-order coma from the total aberration fields, on the framework of the modified nodal aberration theory (NAT), for the perturbed off-axis telescope. Based on the derived aberration functions, two alignment models for the same off-axis two-mirror telescope are(More)
We propose a simplified phase diversity method based on the first-order Taylor expansion of the optical transfer function (OTF) as the light intensity on the pupil plane is not uniform but presents Gaussian distribution. By extending the Zernike polynomial term to the complex field, we regard the distribution of the light intensity as the imaginary part of(More)