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Raman spectroscopy is capable of precisely identifying and analyzing the composition and properties of samples collected from the lunar surface, providing crucial data support for lunar scientific research. However, in situ Raman spectroscopy on the lunar surface faces challenges such as weak Raman scattering from targets, alongside requirements for lightweight and long-distance detection. To address these challenges, time-gated Raman spectroscopy (TG-LRS) based on a passively Q-switched pulsed laser and a linear intensified charge-coupled device (ICCD), which enable simultaneous signal amplification and background suppression, has been developed to evaluate the impact of key operational parameters on Raman signal detection and to explore miniaturization optimization. The TG-LRS system includes a 40 mm zoom telescope, a passively Q-switched 532 nm pulsed laser, a fiber optic delay line, a miniature spectrometer, and a linear ICCD detector. It achieves an electronic gating width under 20 ns. Within a detection range of 1.1–3.0 m, the optimal delay time varies linearly from 20 to 33 ns. Raman signal intensity increases with image intensifier gain, while the signal-to-noise ratio peaks at a gain range of 800–900 V before declining. Furthermore, the effects of focal depth, telescope aperture, laser energy, and integration time were studied. The Raman spectra of lunar minerals were successfully obtained in the lab, confirming the system’s ability to suppress solar background light. This demonstrates the feasibility of in situ Raman spectroscopy on the lunar surface and offers strong technical support for future missions.

Image intensifier tubes (IITs) are the most important modules of night vision devices used in huge numbers by military forces worldwide. Resolution is the most important parameter of IITs that presents information about ability of these devices to produce output images preserving information about details of the observed scenery. Despite its importance, it is still a common practice to measure resolution subjectively, by an observer looking at image of a resolution target created by a tested IIT. A series of attempts have been carried out to develop objective methods for accurate resolution measurement of IITs but with limited success. Accuracy of these methods varies depending on the tested IIT. This paper presents detailed analysis of proposed methods for objective resolution measurement. This analysis has shown that significant variability of accuracy of these methods is caused by one main drawback: the methods do not take into account influence of the spatial noise effect on human perception of image of the resolution target. Thus, an improved method taking into account spatial noise and its impact on target detection has been proposed. The method has been validated through experimental verification that shows accuracy improvements compared to other objective methods. This new approach improves accuracy of measurement of resolution of IITs to a level that can be accepted at professional test stations. In this way, this new method has potential to replace the standard subjective method to measure resolution of IITs and fix the biggest flaw of the standard test stations: measurement subjectivity.

Shear distortion is the defect brought in the manufacturing stage of optical fiber panel of low-light-level (LLL) image intensifier. The traditional detection method of such defects is purely based on visual observation, so the recording measure is rough and the amount of manual intervention is large. According to the above facts, an objective detection method of shear distortion of LLL image intensifier based on global scanning and image patch edge feature analysis is proposed. Firstly, the inclination of parallel lines is calculated to realize the normalized rotation of the target image; Then, the effective area is scanned globally by means of spatial kernel for local defect detection. The image in the kernel is processed to retain only the edge features, and then the proposed shear distortion detection strategy is applied to each edge in the processed image. Finally, the distortion points in the local image are restored to the target image through the image patch spatial coordinates. To substantiate the performance of the proposed method, a series of image tubes with diverse degrees of shear distortion are put into experiments, and the relevant detection technologies are used as the comparison. It yields the conclusion that the proposed method is robust to the background noise, illumination change and image defects to some extent, and is superior to the relevant detection technology in overall performance. Compared with the traditional visual inspection method, this method not only standardizes the recording measure of test results, but also has better time stability.

The results of calculations of electric fields, potentials, and trajectories of photoelectrons calculations of single-channel dual-spectral thermal imager, implemented in the IIT architecture are presented. The values of the optimal potentials on the control electrodes (microchannel plate, reading electrode, and photocathode) that form a picture of the images of objects and ensure the correct reading of the potential relief from the surface of the sensor-converter pyroelectric film of the image thermal receiver under discussion are determined.

A single-channel, two-spectral image receiver of objects emitting in UV radiation, made in the image intensifier tube architecture, was proposed and investigated. With the help of the COMSOL Multiphysics software package, search optimal measurements of the potential on the elements of the image receiver (silicon membrane, germanium and diamond photocathode, MCP input and output sensors) were implemented, which provides the possibility of registering and presence of UV objects in relation to the terrain.

An innovative design of thermal imaging is considered. The results of analysis and calculations of the characteristics of a thermal image receiver (3–15 μm), made in the electron-optical converter architecture, are presented. The spatial dependences of the spontaneous polarization the electric field strengths and the electric potentials on the surface of pyroelectric film are calculated. The characteristics of thermal-field-induced polarization of various pyroelectric films are obtained. The temperature dependences of various pyroelectric films polarizations are calculated by the COMSOL Multiphysics software package based on the finite element method. The possible influences of the piezoelectric effect to the images of the distribution of electric potentials of pyroelectric films are taken into account. The estimates of the values of the main characteristics of the image intensifier tube architecture are obtained.

Flat panel detector (FPD) technology in interventional cardiology is on the increase due to its varied advantages compared to the conventional image intensifier (II) systems. It is not clear whether FPD imparts lower radiation doses compared to II systems though a few studies support this finding. This study intends to compare radiation doses from II and FPD systems for coronaryangiography (CAG) and Percutaneous Transluminal Coronary Angioplasty (PTCA) performed in a tertiary referral center. Radiation doses were measured using dose area product (DAP) meter from patients who underwent CAG (n = 222) and PTCA (n = 75) performed using FPD angiography system. The DAP values from FPD were compared with earlier reported data using II systems from the same referral center where the study was conducted. The mean DAP values from FPD system for CAG and PTCA were 24.35 and 63.64 Gycm 2 and those from II system were 27.71 and 65.44 Gycm 2 . Transition from II to FPD system requires stringent dose optimization strategies right from the initial period of installation.

Optical imaging is commonly used for both scientific and technological applications across industry and academia. In image sensing, a measurement, such as of an object’s position or contour, is performed by computational analysis of a digitized image. An emerging image-sensing paradigm relies on optical systems that—instead of performing imaging—act as encoders that optically compress images into low-dimensional spaces by extracting salient features; however, the performance of these encoders is typically limited by their linearity. Here we report a nonlinear, multilayer optical neural network (ONN) encoder for image sensing based on a commercial image intensifier as an optical-to-optical nonlinear activation function. This nonlinear ONN outperforms similarly sized linear optical encoders across several representative tasks, including machine-vision benchmarks, flow-cytometry image classification and identification of objects in a three-dimensionally printed real scene. For machine-vision tasks, especially those featuring incoherent broadband illumination, our concept allows for a considerable reduction in the requirement of camera resolution and electronic post-processing complexity. In general, image pre-processing with ONNs should enable image-sensing applications that operate accurately with fewer pixels, fewer photons, higher throughput and lower latency.A nonlinear optical neural network image sensor based on an image intensifier enables efficient all-optical image encoding for a variety of machine-vision tasks.

The intensified charge-coupled device (ICCD), known for its exceptional low-light detection performance and time-gating capability, has been widely applied in remote Raman spectroscopy systems. However, existing ICCDs face significant challenges in meeting the comprehensive requirements of high gating speed, high sensitivity, high resolution, miniaturization, and adaptability to extreme environments for the upcoming lunar remote Raman spectroscopy missions. To address these challenges, this study developed a microstrip photocathode (MP-ICCD) specifically designed for lunar remote Raman spectroscopy. A comprehensive testing method was also proposed to evaluate critical performance parameters, including optical gating width, optimal gain voltage, and relative resolution. The MP-ICCD was integrated into a prototype remote Raman spectrometer equipped with a 40 mm aperture telescope and tested under outdoor sunlight conditions. The experimental results demonstrated that the developed MP-ICCD successfully achieved a minimum optical gating width of 6.0 ns and an optimal gain voltage of 870 V, with resolution meeting the requirements for Raman spectroscopy detection. Under outdoor solar illumination, the prototype remote Raman spectrometer utilizing the MP-ICCD accurately detected the Raman spectra of typical lunar minerals, including quartz, olivine, pyroxene, and plagioclase, at a distance of 1.5 m. This study provides essential technical support and experimental validation for the application of MP-ICCD in lunar Raman spectroscopy missions.

As one of the payloads on board the Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) spacecraft, the ultraviolet imager (UVI) aims to capture N2 Lyman–Birge–Hopfield (LBH) aurora continuously on a high-eccentricity orbit. The UVI instrument includes an intensified charge-coupled device (ICCD) for far ultraviolet (FUV) wavelength. It comprises a sealed image intensifier, a relay lens system, a CCD, and a mechanical housing. ICCD’s performance characteristics are evaluated before integrating with the optical system of the UVI, including the quantum efficiency, radiant gain, background characteristics, excess noise factor, image quality, and signal-to-noise ratio (SNR). The testing procedure and results are presented and discussed. The results demonstrate that the comprehensive performance of the detector is good, and provide critical technical support for quantitative applications.