Thus, a four-fold enhancement can be gained in CNR at a 200 µm field-of-view (FOV) by suppressing background speckles.In order to obtain broadband, highly efficient, wide-angle, and polarization-insensitive solar absorbers, we propose a universal configuration consisting of monolayer molybdenum disulfide (MoS2) and the metal-insulator-metal structure, which gives rise to significant absorption enhancement of the MoS2 layer. Light trapping structures with silver square-, circle-, and crossed-shaped resonators are investigated. The localized surface plasmon resonances among the silver resonators induce prominent interaction between the incident photon and MoS2 layer, contributing to efficient absorption of light energy. Simulation results show that the absorber made of square patches enables the best performance and realizes absorptance higher than 90% from 400 to 666 nm and an average absorptance greater than 91% in the range of 400-700 nm. The average light absorption within the MoS2 layer reaches 74% in the visible spectrum, which is one of the highest levels for the existing MoS2-based absorbers. Meanwhile, the polarization-independent designs exhibit good angle tolerance within 50° incidences. Such a universal structure can also obtain broadband and highly efficient absorption by using other transition metal dichalcogenides such as MoSe2, WS2, and WSe2, which indicates that the configuration has great applicability in solar energy absorption of 2D materials. The proposed solar absorbers with simple configuration and broadband absorption in wide incident angles have potential in applications such as solar cells, photovoltaic devices, and blackbody materials.Space astronomical telescopes must test the image stabilization accuracy of their image stabilization system prior to entering the orbit. According to the position characteristics of the fine guidance sensor of telescopes required by the China National Space Administration, a simulation model of moving guide stars is proposed in this study to test the image stabilization accuracy of space telescopes. The simulation model for synchronous moving guide stars is based on the principle of mutual collimation of the diagonal field of view of the optical system of telescope. Realize the multi-field moving guide stars with high synchronization accuracy simulated by the same target source. Compared to traditional methods, this method requires simple manufacturing and has high flexibility. The error sources affecting the simulation accuracy of the moving guide stars are analyzed, and an error model is established. Analysis results show that the simulation accuracy of the moving guide stars can reach 0.046 ' ' . The simulation model of guide stars is verified through experiments in which the influence of the vibration isolation platform is considered. Experiment results show that the simulation accuracy of motion guide stars is 0.036 ' ' , satisfying the accuracy requirements ( less then 0.08 ' ' ) of the accuracy test for the telescope image stabilization of telescopes.Real-time monitoring of structural health conditions for rotary objects is of importance for safety assessments. In this work, an efficient algorithm based on digital image correlation is presented to achieve accurate rotational matching in real time. The proposed algorithm measures rotation in object motion with an integer pixel search followed by a subpixel correlation refinement.  https://www.selleckchem.com/products/kpt-8602.html  In the integer pixel search, the reference subset is rotated inversely to facilitate the correlation computation between the reference and target subsets. Then an independent and global integer pixel search for each point of interest is performed by applying the particle swarm optimization algorithm. Finally, a modified iterative registration algorithm is introduced to refine the displacement in the subpixel level by considering both the rotation angle and displacement components. Simulation and rotation experiments demonstrate that the proposed method achieves rapid and accurate measurements and is an effective method for retrieving the rotation data of rotating structures.In a dynamic far-field diffraction experiment, we calculate the largest Lyapunov exponent of a time series obtained from the optical fluctuations in a dynamic diffraction pattern. The time series is used to characterize the locomotory predictability of an oversampled microscopic species. We use a live nematode, Caenorhabditis elegans, as a model organism to demonstrate our method. The time series is derived from the intensity at one point in the diffraction pattern. This single time series displays chaotic markers in the locomotion of the Caenorhabditis elegans by reconstructing the multidimensional phase space. The average largest Lyapunov exponent (base e) associated with the dynamic diffraction of 10 adult wildtype (N2) Caenorhabditis elegans is 1.27±0.03s-1.A convenient method to fabricate two-dimensional photonic quasicrystal microstructures was experimentally demonstrated by using a rotatable four-wedge prism. Two-dimensional eightfold symmetric quasicrystal microstructures are formed by two groups of twisted square lattices in a photorefractive crystal. The experimental devices of this method are simple and stable without complicated optical adjustment equipment. Optical-induced quasicrystal microstructures are analyzed and verified by magnified imaging and far-field diffraction pattern imaging. The method can be extended to fabricate more complex quasicrystal and moiré lattice microstructures. We numerically demonstrate that this method can be used to fabricate other complex photonic microstructures by using different multi-wedge prisms and adjusting the rotation angle properly.For optically narrowing field depth, we explore the use of annular masks that are coded with the elements of Hadamard matrices. We show that with no further reduction of light throughput, these annular masks can enhance the influence of focus error on the modulation transfer functions (MTF). We report numerical evaluations of the irradiance point spread functions (PSFs), their associated MTFs, and of some digitally generated images. For complementing our assessments, we evaluate the Fisher information of these Walsh-Hadamard, annular masks. We suggest an optical technique for breaking 3-D scenes into several 2-D sliced frames by translating out-of-focus images into background noise.