Meierhart3623

Small-surface optical components with complex shapes and high-precision requirements are increasingly needed in the fields of mobile communications, in vivo diagnosis, and other fields. Some scholars have studied and proposed a two-dimensional vibration actuated polishing (2D-VAP) method based on small polishing tools for the preparation of small-surface optical elements. Using the nonresonant 2D-VAP device developed by the author, the frequency and amplitude of 2D-VAP are precisely adjusted to generate a random-like Lissajous polishing trajectory, which can overcome the problem that most of the existing 2D-VAP methods generate a circular or elliptical polishing trajectory at the small polishing tool, resulting in leaving periodic polishing marks on the workpiece surface. The removal function model under the condition of random-like Lissajous polishing motion with a small polishing tool is established. In addition, the removal function verification experiments and surface polishing experiments are carried out. The experimental results show that the measured removal function is in good agreement with that obtained by numerical simulation. Compared with the circular polishing trajectory, the random-like Lissajous polishing trajectory can significantly improve the material removal rate, and there are no obvious periodic polishing marks on the workpiece surface.A compact near-eye visor (NEV) system that can guide light from a display to the eye could transform augmented reality (AR) technology. Unfortunately, existing implementations of such an NEV either suffer from small field of view or chromatic aberrations. See-through quality and bulkiness further make the overall performance of the visors unsuitable for a seamless user experience. Metasurfaces are an emerging class of nanophotonic elements that can dramatically reduce the size of optical elements while enhancing functionality. In this paper, we present a design of composite metasurfaces for an ultracompact NEV. We simulate the performance of a proof-of-principle visor corrected for chromatic aberrations while providing a large display field of view (>77∘ both horizontally and vertically) and good see-through quality [>70% transmission and less than a wavelength root mean-square (RMS) wavefront error over the whole visible wavelength range] as needed for an immersive AR experience.In this paper, a multicomponent gas detection system based on photoacoustic spectroscopy (PAS) is proposed with a combination of frequency division multiplexing (FDM) and time division multiplexing (TDM), combining a resonance photoacoustic cell and broadband microphone. A PAS gas cell with a wide frequency response bandwidth was used to achieve the FDM by selecting a specific modulation frequency of each component gas. The sawtooth wave driver current of each laser was output at a constant time interval for achieving the TDM. Compared with the laser channel control using a photoswitch, the driver current control was a simpler and more convenient means to implement TDM. The four gas components of methane (CH4), water (H2O) vapor, carbon dioxide (CO2), and acetylene (C2H2) were selected as sample gases for testing the feasibility of the method. GNE-317 ic50 The experimental results showed that the gas detection limits of CH4, H2O vapor, CO2, and C2H2 were 75.435, 2.502, 341.960, and 4.284 ppm, respectively. In addition, the linear fittings of gas concentration were 0.99386, 0.99772, 0.98995, and 0.98955, respectively.We present geometrical and physical optics simulation results for the Simons Observatory Large Aperture Telescope. This work was developed as part of the general design process for the telescope, allowing us to evaluate the impact of various design choices on performance metrics and potential systematic effects. The primary goal of the simulations was to evaluate the final design of the reflectors and the cold optics that are now being built. We describe nonsequential ray tracing used to inform the design of the cold optics, including absorbers internal to each optics tube. We discuss ray tracing simulations of the telescope structure that allow us to determine geometries that minimize detector loading and mitigate spurious near-field effects that have not been resolved by the internal baffling. We also describe physical optics simulations, performed over a range of frequencies and field locations, that produce estimates of monochromatic far-field beam patterns, which in turn are used to gauge general optical performance. Finally, we describe simulations that shed light on beam sidelobes from panel gap diffraction.Digital holographic microscopy (DHM) is a technique that has high potential for analyzing biological samples and has been successfully applied to the study of cells and cell lines providing information about important parameters such as refractive index, morphology, and dry mass, among others; it has also found applicability to study the effects of therapeutic treatments. Finding the size and shape of cells is important since they tend to change in the presence of some pathologies. In this research work, we obtain the morphology thickness and refractive index of the A375 melanoma cell line through a slight tilting of the cell in a DHM setup. Further, the development of a novel mathematical expression based on this tilt and in the optical phase difference is presented. We show images of melanoma cells with the refractive index information included, and their morphology thickness as rendered from the holographic phase maps recorded with DHM.Ghost imaging (GI) can reconstruct the image of an object when the light traveling from the object to the detector is scattered or distorted. It is usually used in complicated environments, where the environmental light may heavily impact measurement. However, the traditional GI algorithm will be seriously affected if the environmental light changes during the measurement. In this paper, we analyze the frequency of environmental light and the light source, and introduce a digital filtering method that can improve the image quality of the traditional GI algorithm. Compared to the traditional GI algorithm, the digital filtering method can obtain an image even if the environmental light changes seriously.