Combining information from several channels of the Norwegian Institute for Air Research (NILU-UV) irradiance meter, one may determine the total ozone column (TOC) amount. A NILU-UV instrument has been deployed and operated on two locations at Troll research station in Jutulsessen, Queen Maud Land, Antarctica, for several years. The method used to determine the TOC amount is presented, and the derived TOC values are compared with those obtained from the Ozone Monitoring Instrument (OMI) located on NASA's AURA satellite. The findings show that the NILU-UV TOC amounts correlate well with the results of the OMI and that the NILU-UV instruments are suitable for monitoring the long-term change and development of the ozone hole. Because of the large footprint of OMI, NILU-UV is a more suitable instrument for local measurements.Polarimetric imaging detection is a relatively new and largely undeveloped field. Although convolutional neural networks (CNNs) have achieved great success in two-dimensional (2D) normal intensity images in the field of target detection, traditional CNN methods have not been widely applied to optical polarimetric images, and they cannot take full advantage of the connection between different polarimetric images. To solve this problem, three-dimensional (3D) convolutions are adopted to consider the relationship between S0, S1, and S2 images as a third dimension. Based on the 3D convolutions, a CNN with 3D and 2D convolutional layers is introduced to further improve the success rate of target detection with limited polarimetric images. The evaluations in different natural backgrounds reveal that the proposed method achieves higher detection accuracy than that of two traditional methods for comparison.Synthetic aperture ladar is an emerging sensor technology providing high-resolution imagery of targets from long standoff ranges. Atmospheric turbulence corrupts the collected phase history data with spatially variant phase perturbations, impacting resolution and contrast of reconstructed imagery. We explore the efficacy of model-based reconstruction algorithms with model error corrections to mitigate the deleterious effects of atmospheric turbulence and restore image quality. We present results from model error correction techniques utilizing spatially invariant, spatially variant, and a model-based atmospheric phase error correction. We quantify the performance of all algorithms using an atmospheric ray-trace simulation.Full-waveform LiDAR systems have been developed owing to their superiority in terms of high precision and resolution. However, further improving the imaging speed and resolution continues to be a problem. In this study, we propose an optical orthogonal code division multiple access (OCDMA) coding and 3D imaging technique, and a non-scanning full-waveform LiDAR system is first demonstrated. Encoding, multiplexing, and decoding are the essential modules of the OCDMA LiDAR system, which use M detectors and N-bits code to achieve high-accuracy decomposition for $\rm M \times \rm N$M×N pixels. In this paper, a complete 3D imaging LiDAR system is introduced, and the implementation of encoding and decoding is also illustrated. To prove that the technology is scientific and effective, an imaging experiment is carried out. The experimental result indicates that a system with only four avalanche photodiodes (APDs) can achieve 256 pixels. Moreover, the vertical resolution is about 1.8 cm and the range resolution is 15 cm at the distance of 40 m.Squint-looking differential synthetic aperture ladar (DSAL) is reported with detailed signal processing mathematics and high-resolution experimental demonstrations. Based on the DSAL principle and standard squint-looking synthetic aperture radar theory, the data processing procedures on squint-looking DSAL image formation are obtained. The experimental DSAL setup, operating in "step-stop" strip map mode, adopts a frequency chirped laser with a wavelength of 1550 nm as the illuminating source and a specially designed random phase generator to introduce large common mode random phase error (RPE) into the phase history data of both receiving sub-apertures. High-resolution DSAL images of a cooperative target at a distance of 1.85 m and squint-looking angle of $-10^\circ$-10∘ or $+10^\circ$+10∘ are demonstrated. The DSAL images, with or without large RPE, are all well focused by straightforwardly following the given data processing steps. The result illustrates that the DSAL technique is robust in removing common mode phase errors in squint-looking configuration.This study proposes a single-step integrated optical fabrication scheme utilizing a 3D printer using digital light processing technology. Strong light confinement in the fabricated structure is realized through the introduction of an elevated (tower-shaped) waveguide in a transparent photosensitive resin (PX-8880). The fabrication is optimized to maximize light confinement through varying the dimensions of the guiding region and the tower structure. Benefiting from the surface roughness produced by the slicing process in the 3D printing (50 µm resolution), the fabricated structure was tested for vapor sensing. Obvious intensity dynamics have been reported due to the change of the optical scattering due to the presence of vapor as well as polymer vapor interaction. Though the reported response time is long, further optimization can lead to practical operation time.An experimental method to remove modal instabilities induced by thermoelastic deformation in optical high-finesse resonators is presented and experimentally investigated in this paper. The method is found suitable for multi-mirror folded monolithic and compact cavities, such as those used in the particle accelerator environment. It is also suitable for very high stacked average power. Here we demonstrate stable operation at the 200 kW intracavity average power.We design a standing semiconductor-dielectric core-shell nanocone array (CSNCA) that can not only concentrate the incident light into the structure, but also confine most of the concentrated light to the semiconductor (indium phosphide) core region, which remarkably enhances the light absorption of the more material-saving semiconductor core.  https://www.selleckchem.com/  We find guided resonance features along the radial and FP-resonant features along the axial direction by analyzing the electric field patterns at the absorption spectrum peaks. The CSNCA can support multiple higher-order HE modes, in comparison to the bare nanocone array (BNCA). Results based on detailed balance analysis demonstrate that the core-shell design gives rise to higher short-circuit current and open-circuit voltage, and thus higher power conversion efficiency. Detailed research is focused on the 1 µm high CSNCAs, and a remarkable power conversion efficiency enhancement (42.2%) is gained compared with the BNCAs.