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A synchronous multi-angle scattered light field measurement system is constructed in this study to overcome issues with current systems in the field of multi-angle remote sensing. A mathematical model of the scattered light field measurement was established. An off-axis catadioptric optical system was designed to satisfy hemispheric spatial scattered light field measurements in a zenith angle range of 68°. The off-axis calibration model was established, and the spatial relationship was calibrated. The measurement accuracy was calibrated via an integrating sphere light source, and the maximum measurement relative error was −3.71%. The scattered light field of the reference diffuse reflective target plate Labsphere Permaflect-50 and 304 stainless steel was simulated under an incident light irradiation range within the zenith angle of −23.5^∘ to +23.5^∘, and synchronous measurement of the multi-angle scattered light field of the sample was realized. The measurement system could provide technical support for building the complex model of multi-angle reflection/radiation from the earth’s surface, multi-angle sensor radiation calibration, and improvement of the physical parameter inversion accuracy of observation targets.

Combination chemotherapy can slow the emergence of resistance, but can also lead to a significant exacerbation of off-target effects. Mediated drug release can ameliorate this situation: in this study, mitoxantrone (MTO) and doxorubicin (DOX) were co-loaded onto a nanodiamond (ND) scaffold, through physical adsorption, to prepare an ND/MTO/DOX (NMD) nanodrug. The drug loading of MTO and DOX were 119 ± 3 μg mg−1and 60 ± 3 μg mg−1, respectively. This NMD exhibits excellent stability with negligible drug leakage upon storage. The NMD nanoparticles enter cells viathe clathrin and caveolae co-mediated endocytosis pathways and primarily remain within the lysosomes. Cytotoxicity tests showed that the NMD has an enhanced synergistic effect compared with an ND loaded with either drug alone, and has a slow but effective rate of drug release. Intraperitoneal injection of the NMD-drug into tumor-bearing mice demonstrated that the NMD rapidly localizes to the tumor site with very limited dispersion to other organs. The NMD strongly suppressed tumor growth in vivowith significantly reduced toxic side effects compared to mice treated with the free drugs. These results suggest that the as-prepared NMD has potential clinical applications for the targeted co-delivery of multiple chemotherapeutics.

This paper proposes a more accurate eccentricity and tilt measurement method based on Young’s interference experiment. The basic principle of the method is introduced first before the method is simulated. Then the results are obtained when a to-be-adjusted focusing lens with eccentricity and tilt is simulated. The optical sensitivity also is obtained from these simulation results, and the expression for the change in optical path length caused by eccentricity and tilt is analyzed. Use of this method to detect eccentricity and tilt and assist in adjustment of the system allows the instrument to achieve higher accuracy and thus obtain improved imaging quality and spectral resolution.

A miniaturized portable short-wave infrared imaging spectroscopy optical system is designed based on a prism-grating dispersion module. We established a prism-grating model to calculate the optimal combination of prism and grating parameters to balance spectral smile over the entire band. The design method for the telescopic system and spectroscopic system combines independent design with integrated optimization. The system’s spectral smile and spectral keystone are less than 15 μm and less than half a pixel, respectively. The total optical system length is 230 mm, which meets the miniaturization requirements for airborne systems. The system’s spatial resolution is 1 mrad, and its average spectral resolution is 6.2 nm. The system offers the advantages of large relative aperture, excellent imaging quality, reduced spectral smile, and spectral keystone, miniaturization, and portability.

Spatial heterodyne Raman spectrometry (SHRS) is a spectral analysis technique used to study material structures and compositions. We propose a multi-grating SHRS system that uses a multi-grating module rather than the single grating used to terminate each arm in traditional spatial heterodyne spectrometry (SHS). The proposed system not only retains the advantages of traditional SHS but also resolves the mutual limitation between system spectral range and resolution. The increased spectral range and resolution that can be achieved in detection are dependent on the number of sub-gratings used in the module. A verification system was built using 130 gr/mm and 150 gr/mm sub-gratings and calibrated. Under different experimental conditions (including laser power, integration time, container material and thickness, pure and mixed samples, and standoff experiments), the backscattered Raman spectra of different types of targets (including organic solutions, inorganic powders, and minerals) were tested. The multi-grating SHRS shows good performance for broad spectral range and high-resolution Raman detection.

In an echelle spectrometer equipped with a prism cross-dispersion element, wavelength calibration is very difficult because of the complex, nonlinear interaction between the prism and the echelle grating. From the spectrometer geometry and the dispersion equations for the prism and the grating, a detailed mathematical model for wavelength calibration is derived that fits the refractive index of the prism in real time. An expression relating the refractive index, wavelength, and image coordinates is constructed, and standard wavelength sources and image positions are adopted to timely calculate the refractive index, which is affected by ambient factors such as temperature and air pressure. Experimental results indicate that the fitting accuracy of the refractive index in real time approaches 10^−4, while the wavelength accuracy approaches 10^−3  nm for the entire spectral range.

A spectral reduction algorithm for an échelle spectrometer with spherical mirrors that builds a one-to-one correspondence between the wavelength and pixel position is proposed. The algorithm accuracy is improved by calculating the offset distance of the principal ray from the center of the image plane in the two-dimensional vertical direction and compensating the spectral line bending from the reflecting prism. The simulation and experimental results verify that the maximum deviation of the entire image plane is less than one pixel. This algorithm ensures that the wavelengths calculated from spectrograms have a high spectral resolution, meaning the precision from the spectral analysis reaches engineering standards of practice.

The designs of 300 mm ruling engine producing gratings and echelles under interferometric control (CIOMP-2) are presented. A new ruling-tool carriage system and its driving mechanism—which are easy to manufacture—are proposed. A new blank carriage system, controlled by a dual-frequency laser interferometer and a piezoelectric actuator, is designed. The CIOMP-2 ruling engine can now rule grating blanks with dimensions up to 300  mm×300  mm, and mainly rules gratings with grating constants between 10 and 2400  lines/mm. The wavelength range of CIOMP-2 gratings is from ultraviolet to mid-infrared wavelengths. Experiments show that the new ruling-tool carriage system works well and stability of motion is improved with the help of a flexure-hinge structure, and the threefold standard deviation values of the blank carriage positioning errors are less than ∼5  nm. For 600  line/mm gratings (diffraction order m=−1), the scatter intensities and ghosts reach 10^−5 of the maximum intensity. The scatter intensities and ghost of gratings ruled with CIOMP-2 are low, and no Rowland ghosts are visible. The gratings ruled by CIOMP-2 have high diffraction efficiency and resolving power. CIOMP-2 can also produce varied-line-space, bend-line, and aberration-reducing gratings and echelles.

In order to solve the problem that the grating quality cannot be monitored directly in real time, we provided a method based on Rayleigh criterion with our designing optical measurement structure to measure yaw and displacement errors of a grating ruling machine feeding system. Gratings are ruled with or without errors correction by the real-time monitoring system . It shows that the resolution obtained without errors correction is reduced from 99.97% to 87.47% of theoretical value, while the resolution obtained with errors correction is stable, remaining at 99.99%–97.21%. The experimental result is that the grating quality can be guaranteed by monitoring grating resolution in real time.