The key to achromatic 2-phase modulation across the broadband spectrum lies in controlling the dispersion of all phase units within the broadband domain. This paper presents broadband designs of optical elements based on multilayer subwavelength structures, highlighting the ability to control, on a significantly larger scale than monolayer designs, the phase and phase dispersion of individual structural components. The emergence of the desired dispersion-control attributes resulted from a dispersion-cooperation approach and the vertical mode-coupling interactions between the topmost and bottommost layers. An infrared design composed of two vertically aligned titanium dioxide (TiO2) and silicon (Si) nanoantennas, with a silicon dioxide (SiO2) spacer layer intervening, has been showcased. The three-octave bandwidth demonstrated an average efficiency exceeding 70%. This work demonstrates the substantial advantages of broadband optical systems, including their application in spectral imaging and augmented reality, by means of DOEs.

A line-of-sight coating uniformity model requires a normalized source distribution, making all material traceable. A point source within a void coating chamber is the subject of this validation. We can now evaluate the effectiveness of source material utilization in a coating geometry to pinpoint the fraction of evaporated source material that is deposited on the chosen optical components. To illustrate a planetary motion system, we determine this utilization metric and two non-uniformity factors considering a broad range of input parameters. These are the distance between the source and the rotary drive system, and the lateral shift of the source from the machine's central axis. Understanding the geometry trade-offs is facilitated by contour plot visualizations in this two-dimensional parameter space.

The application of Fourier transform theory to rugate filter synthesis has proven Fourier transform to be a powerful mathematical tool for achieving diverse spectral responses. This synthesis method links transmittance, symbolized as Q, to its refractive index profile using the Fourier transformation. Variations in transmittance across wavelengths are mirrored by changes in refractive index across film thicknesses. Examining the relationship between spatial frequencies, represented by the rugate index profile's optical thickness, and improved spectral response is the focus of this work. Furthermore, this work considers the impact of increasing the rugate profile's optical thickness on reproducing the intended spectral response. To reduce the lower and upper refractive indices, the stored wave was subjected to the inverse Fourier transform refinement method. We present three illustrative examples and their corresponding outcomes.

Considering its suitable optical constants, FeCo/Si presents itself as a compelling material combination for polarized neutron supermirrors. this website Using a methodical approach, five FeCo/Si multilayers were developed, each with an incrementally thicker FeCo layer. Grazing incidence x-ray reflectometry and high-resolution transmission electron microscopy were utilized to study the interfacial asymmetry and interdiffusion. The crystalline nature of FeCo layers was ascertained through the application of selected area electron diffraction. Further investigation of FeCo/Si multilayers demonstrated the existence of asymmetric interface diffusion layers. The 40-nanometer mark signified the beginning of the FeCo layer's structural change, shifting from an amorphous state to a crystalline one.

Substation digitalization frequently employs automated identification of single-pointer meters, demanding precise meter value retrieval. Current methods for identifying single-pointer meters exhibit limitations in their universal applicability, only enabling the identification of a single meter type. This study introduces a hybrid approach to identifying single-pointer meters. Modeling the single-pointer meter's input image yields prior knowledge about its characteristics, such as the template image, pointer, dial positions, and scale values. Through feature point matching, image alignment compensates for slight shifts in camera angle, using output from a convolutional neural network to create input and template images. For rotation template matching, a pixel loss-free method of correcting arbitrary point rotations in images is now presented. Through a process of aligning the pointer template with the rotated gray mask image of the dial input, the optimal rotation angle is calculated, which is essential to determining the meter value. The experimental results validate the method's capability to precisely identify nine different kinds of single-pointer meters across various ambient illuminations in substations. Substations can leverage this study's findings to evaluate the economic value of different single-pointer meter types.

Analyses of spectral gratings, characterized by a wavelength-scale period, have highlighted important aspects of their diffraction efficiency and characteristics. Despite the need, an investigation into the properties of a diffraction grating possessing an ultra-long pitch (over several hundred wavelengths, >100m) and exceptionally deep grooves (over dozens of micrometers) has yet to be performed. Applying the rigorous coupled-wave analysis (RCWA) approach, we analyzed the diffraction efficiency of these gratings, verifying that the theoretical predictions from RCWA were consistent with the experimental results for wide-angle beam spreading. Beyond that, a grating with a long period and a deep groove produces a small diffraction angle with consistent efficiency, thus enabling the transformation of a point-like distribution into a linear distribution at a short working distance and a discrete distribution for a large working distance. In a range of applications, including level detectors, precise measurement systems, multi-point LiDAR sources, and security apparatus, a wide-angle line laser with a lengthy grating period shows promise.

Indoor free-space optical communication (FSO) exhibits a significantly higher bandwidth potential than radio frequency links, but this advantage is offset by a trade-off between the area covered and the received power of the signal. this website This paper details a dynamic indoor free-space optical (FSO) system, utilizing a line-of-sight optical connection and sophisticated beam manipulation techniques. A passive target acquisition method is employed in the optical link described here, achieved by combining a beam-steering and beam-shaping transmitter with a receiver featuring a ring-shaped retroreflector. this website The receiver's position can be determined by the transmitter with millimeter accuracy over a three-meter distance, thanks to an effective beam scanning algorithm, within a time of 11620005 seconds, regardless of its placement. This covers a vertical angle of 1125 degrees and a horizontal angle of 1875 degrees. We experimentally validate a 1 Gbit/s data rate with bit error rates below 4.1 x 10^-7, thanks to the efficient use of a 2 mW output power 850 nm laser diode.

This paper delves into the rapid charge transfer mechanism of lock-in pixels, critical components within time-of-flight 3D image sensors. Principal analysis leads to the development of a mathematical model that describes potential distribution in various comb-shaped pinned photodiodes (PPDs). A model-driven investigation into the effect of diverse comb configurations on the accelerating electric field in PPD is presented. Employing the semiconductor device simulation tool SPECTRA, the model's effectiveness is confirmed, and the simulation's outcomes are analyzed and explored in detail. An increase in comb tooth angle produces more pronounced potential changes when the comb tooth width is narrow or medium, whereas a wide comb tooth width exhibits a constant potential even with a steep rise in comb tooth angle. To design pixel electron transfer rapidly and resolve image lag, the proposed mathematical model provides valuable guidance.

To the best of our knowledge, an experimental demonstration of the novel multi-wavelength Brillouin random fiber laser, TOP-MWBRFL, is presented, exhibiting triple Brillouin frequency shift channels and high polarization orthogonality between adjacent wavelengths. The TOP-MWBRFL's construction takes the form of a ring, created by the concatenation of two Brillouin random cavities implemented with single-mode fiber (SMF) and one Brillouin random cavity comprised of polarization-maintaining fiber (PMF). Stimulated Brillouin scattering's impact on polarization in long-distance SMFs and PMFs results in linearly related polarization states of light from random SMF cavities to the pump light's polarization. Meanwhile, the polarization of light from PMF random cavities remains consistently fixed to one of the fiber's principal polarization directions. Therefore, the TOP-MWBRFL is capable of emitting multiple wavelengths of light with a high polarization extinction ratio exceeding 35dB between wavelengths without the requirement for precise polarization feedback adjustments. The TOP-MWBRFL's capabilities extend to operating in a single polarization mode for stable multi-wavelength lasing, where the SOP uniformity reaches a high of 37 dB.

Satellite-based synthetic aperture radar's detection capabilities require immediate augmentation by a large antenna array, extending 100 meters in length. In the large antenna, structural deformation is a source of phase errors, substantially affecting its gain; consequently, real-time, high-precision antenna profile measurements are essential for active phase correction and, ultimately, maximizing the antenna's gain. Nonetheless, the circumstances of antenna in-orbit measurements are exceptionally demanding, stemming from the limited locations for measurement instrument installations, the vast areas encompassing the measurements, the considerable distances to be measured, and the volatile measurement environments. In order to resolve the challenges, we introduce a three-dimensional displacement measurement approach for the antenna plate, incorporating laser distance measurement and digital image correlation (DIC).