Photoelectronic Technology Committee Conferences最新文献

{"title":"An enhanced moment matching method to destriping EO-1/Hyperion data","authors":"Y. Bao, C. Yue, Hongyan He","doi":"10.1117/12.2179698","DOIUrl":"https://doi.org/10.1117/12.2179698","url":null,"abstract":"The striping noise can obscure the true radiation information in the images, reduce the accuracy of hyperspectral images, and have serious effect for visual interpretation and further results based on spectral analyses. This paper introduces the principle of moment matching method, emphasizes the analysis of the formative reason for “edge effect”, and then proposes an enhanced method to destripe EO-1/Hyperion data. The method for destriping has been introduced as well in this paper to compare with the moment matching method from both visual effect and quantitative assessment. It shows that the proposed method could achieve the greater effect for destriping EO-1/Hyperion data.","PeriodicalId":225534,"journal":{"name":"Photoelectronic Technology Committee Conferences","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125411613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spectroscopic properties of Nd3+/Yb3+ co-doped in lithium aluminum silicate glass for 1.0 μm fiber laser","authors":"Kexuan Han, F. Yu, Yanyan Guo","doi":"10.1117/12.2180267","DOIUrl":"https://doi.org/10.1117/12.2180267","url":null,"abstract":"The Nd3+, Yb3+ singly doped and Nd3+ /Yb3+ co-doped lithium aluminum silicate glasses are fabricated by using a conventional melt quenching technique in air atmosphere, with the molar composition of (60-a-b)SiO2-3Al2O3-20Li2O-12MgO-5CaO-aNd2O3-bYb2O3 (with a=0, 0.25, 0.5, 1 and b=0,2). The Spectroscopic properties of 1.0 μm emission and Luminescence lifetime in Nd3+ /Yb3+ co-doped lithium aluminum silicate glasses are investigated under 808 nm excitation. The Judd–Ofelt theory is used to study the spectroscopic properties of Nd3+ . Meanwhile, the emission cross-section of Yb3+ are obtained by using the reciprocity method. A broad emission band from 950 to 1,100 nm is detected when the Nd3+ /Yb3+ co-doped in lithium aluminum silicate glasses excited by 808 nm LD. The energy transfer process from Nd3+ →Yb3+ co-doped in lithium aluminum silicate glasses is described in this paper.","PeriodicalId":225534,"journal":{"name":"Photoelectronic Technology Committee Conferences","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126924004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent development of infrared tunable filter","authors":"Dafu Liu, Qin-fei Xu, D. Mo","doi":"10.1117/12.2179550","DOIUrl":"https://doi.org/10.1117/12.2179550","url":null,"abstract":"Researchers are engaging on tunable infrared (IR) filters, miniature Fabry-Perot optical devices, to operate IR detector like a spectrometer. This kind of devices was used in astronomical detection field in the 1950s. To meet the miniature, lightweight requirements of the optical detection system, researchers began to make small, lightweight, and cheap tunable IR filters. Nowadays researchers have applied a variety of different structures and the IR filter, and are attempting to integrate them with IR detectors directly. Tunable filter thin film mechanical and thermal properties, and working conditions will affect the tunable filter optical performance. In this article we give two main influencing factors, interface roughness and curvature effect. we also present and discuss the current development of FPF in different groups around the world.","PeriodicalId":225534,"journal":{"name":"Photoelectronic Technology Committee Conferences","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116540407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dark-current characteristics of GaN-based UV avalanche photodiodes","authors":"Jin-tong Xu, Chao-wen Chang, Xiang-yang Li","doi":"10.1117/12.2180819","DOIUrl":"https://doi.org/10.1117/12.2180819","url":null,"abstract":"For UV detecting, it needs high ratio of signal to noise, which means high responsibility and low noise. GaN-based avalanche photodiodes can provide a high internal photocurrent gain. In this paper, we report the testing and characterization of GaN based thin film materials, optimization design of device structure, the device etching and passivation technology, and the photoelectric characteristics of the devices. Also, uniformity of the device was obtained. The relationship between dark current and material quality or device processes was the focus of this study. GaN based material with high aluminum components have high density defects. Scanning electron microscope, cathodoluminescence spectra, X-ray double crystal diffraction and transmission spectroscopy testing were employed to evaluate the quality of GaN-based material. It shows that patterned sapphire substrate or thick AlN buffer layer is more effective to get high quality materials. GaN-based materials have larger hole ionization coefficient, so back incident structure were adopted to maximize the hole-derived multiplication course and it was helped to get a smaller multiplication noise. The device with separate absorption and multiplication regions is also prospective to reduce the avalanche noise. According to AlGaN based material characteristics and actual device fabrication, device structure was optimized further. Low physical damage inductively coupled plasma (ICP) etching method was used to etch mesa and wet etching method was employed to treat mesa damage. Silica is passivation material of device mesa. For solar-blind ultraviolet device, it is necessary to adopt a wider bandgap material than AlGaN material. The current-voltage characteristics under reverse bias were measured in darkness and under UV illumination. The distribution of dark current and response of different devices was obtained. In short, for GaN-based UV avalanche photodiode, dark current was related to high density dislocation of thin film materials and device processes, especially the mesa etching and passivation. More and more proofs reveal that the mesa formation course even plays the most important role in generation of dark current.","PeriodicalId":225534,"journal":{"name":"Photoelectronic Technology Committee Conferences","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125205382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Visual saliency detection based on modeling the spatial Gaussianity","authors":"H. Ju","doi":"10.1117/12.2182055","DOIUrl":"https://doi.org/10.1117/12.2182055","url":null,"abstract":"In this paper, a novel salient object detection method based on modeling the spatial anomalies is presented. The proposed framework is inspired by the biological mechanism that human eyes are sensitive to the unusual and anomalous objects among complex background. It is supposed that a natural image can be seen as a combination of some similar or dissimilar basic patches, and there is a direct relationship between its saliency and anomaly. Some patches share high degree of similarity and have a vast number of quantity. They usually make up the background of an image. On the other hand, some patches present strong rarity and specificity. We name these patches “anomalies”. Generally, anomalous patch is a reflection of the edge or some special colors and textures in an image, and these pattern cannot be well “explained” by their surroundings. Human eyes show great interests in these anomalous patterns, and will automatically pick out the anomalous parts of an image as the salient regions. To better evaluate the anomaly degree of the basic patches and exploit their nonlinear statistical characteristics, a multivariate Gaussian distribution saliency evaluation model is proposed. In this way, objects with anomalous patterns usually appear as the outliers in the Gaussian distribution, and we identify these anomalous objects as salient ones. Experiments are conducted on the well-known MSRA saliency detection dataset. Compared with other recent developed visual saliency detection methods, our method suggests significant advantages.","PeriodicalId":225534,"journal":{"name":"Photoelectronic Technology Committee Conferences","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122637681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electroluminescence of cubic boron nitride single crystal flakes with color-zoning","authors":"X. Liu, Shuang Wang, Zhanguo Chen, G. Jia, T. Bian, Lixin Hou, Qi Wang, Nian Liu","doi":"10.1117/12.2180321","DOIUrl":"https://doi.org/10.1117/12.2180321","url":null,"abstract":"The current-voltage (I-V) characteristics and phenomena of electroluminescence of cubic boron nitride (cBN) single crystal flakes with color-zoning under extremely non-uniform electric fields (ENUEFs) induced by needle-plate electrodes were observed. When a cBN flake with sizes of 0.3×0.3×0.1 mm3 was tightly fixed between the tungsten needle and brass plate electrodes in the atmosphere, the I-V relationship exhibited nonlinearity, and peculiar phenomena of electroluminescence with bright blue-violet light appeared at the bias voltage in a range of 700-1200 V. The current-controlled differential negative resistance was synchronously observed. The electroluminescent phenomena were somewhat different for cases of the needle electrode respectively contacting to the amber and transparent zones. The electroluminescent radiations of cBN flakes biased at voltages with a range of 600-1550 V were also investigated in vacuum. In a vacuum chamber, the green emitting phosphor spread around the cBN flake might be excited by the vacuum ultraviolet (VUV) emission from the cBN crystal, and the green fluorescence was observed by naked eyes. The VUV radiation spectrum with a peak wavelength of 149 nm was measured. In the atmosphere, the blue-violet light emission may be the gas discharge resulted from the air ionization induced by the VUV emission from the cBN crystal under the ENUEF, and the ENUEF subsequently keeps the air discharging. The VUV emission from the cBN crystal under the ENUEF can be caused by the original interband transition and the subsequent intraband transfer for electrons, and the final electron-hole direct recombination.","PeriodicalId":225534,"journal":{"name":"Photoelectronic Technology Committee Conferences","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131274781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A hyperspectral image optimizing method based on sub-pixel MTF analysis","authors":"Yun Wang, Kai Li, Jinqiang Wang, Yajie Zhu","doi":"10.1117/12.2182747","DOIUrl":"https://doi.org/10.1117/12.2182747","url":null,"abstract":"Hyperspectral imaging is used to collect tens or hundreds of images continuously divided across electromagnetic spectrum so that the details under different wavelengths could be represented. A popular hyperspectral imaging methods uses a tunable optical band-pass filter settled in front of the focal plane to acquire images of different wavelengths. In order to alleviate the influence of chromatic aberration in some segments in a hyperspectral series, in this paper, a hyperspectral optimizing method uses sub-pixel MTF to evaluate image blurring quality was provided. This method acquired the edge feature in the target window by means of the line spread function (LSF) to calculate the reliable position of the edge feature, then the evaluation grid in each line was interpolated by the real pixel value based on its relative position to the optimal edge and the sub-pixel MTF was used to analyze the image in frequency domain, by which MTF calculation dimension was increased. The sub-pixel MTF evaluation was reliable, since no image rotation and pixel value estimation was needed, and no artificial information was introduced. With theoretical analysis, the method proposed in this paper is reliable and efficient when evaluation the common images with edges of small tilt angle in real scene. It also provided a direction for the following hyperspectral image blurring evaluation and the real-time focal plane adjustment in real time in related imaging system.","PeriodicalId":225534,"journal":{"name":"Photoelectronic Technology Committee Conferences","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132609664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two methods for characterizing the electrical properties of InAsSb film grown by liquid phase epitaxy","authors":"Y. Lv, Shuhong Hu, Yonggang Xu, Yang Wang, Guolin Yu, N. Dai","doi":"10.1117/12.2179766","DOIUrl":"https://doi.org/10.1117/12.2179766","url":null,"abstract":"High-quality InAs1-xSbx films with x=0.06 have been successfully grown on InAs (100) substrates by liquid phase epitaxy. Two methods are used to characterize the electrical properties of InAsSb film. One is to grow InAsSb epilayer on p-type InAs substrate, which, in combination with the n-type epilayer, forms a p-n junction to prevent the parallel conduction from the substrate. The other is that both the conductive InAs substrate and the dislocation layer between InAs and InAsSb are removed completely by chemical mechanical polishing method to get InAsSb film glued onto insulating sapphire substrate. The influence of conductive InAs substrate on the electrical properties of InAsSb film is eliminated effectively.","PeriodicalId":225534,"journal":{"name":"Photoelectronic Technology Committee Conferences","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123222789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Concept and realization of measuring spatial structure of atmospheric optical turbulence by the fiber optical turbulence sensor array","authors":"Qian Wang, Haiping Mei, R. Rao","doi":"10.1117/12.2178434","DOIUrl":"https://doi.org/10.1117/12.2178434","url":null,"abstract":"In this article, a high quality fiber optical turbulence sensing array contains several sensors is proposed to obtain time series of air refractive index fluctuations. A fixed sensor is supposed to be set as the origin and others to be arranged in Cartesian coordinates respectively. Under the spatial configurations above, two-point correlation algorithm is used to give two order structure parameters and multipoint correlation algorithm for more structure information about scalar turbulence. For each direction, two-point spatial correlation coefficients varying with distance are provided. Meanwhile spatial power spectrum and outer-scales according to the data are introduced. Multipoint correlations can give more structure information such as the interactions between scales and the spatial structure of relevant fluctuations. In the one-dimension circumstance for instance the x-axis, spatial correlation coefficient tends to take oscillation. After a short-time averaging, it tends to decrease with the increase of spatial displacement, and then tends to zero after outer scale. Further study show that within the limit of outer scale, diurnal variation of the spatial correlation coefficient and intensity reveal a higher similarity, the relevancy is about 60% and keeps stable; once the distance goes across the outer scale, they are uncorrelated. In short, utilizing the fiber optical turbulence sensing array is a new method for measuring spatial correlation of optical turbulence. It can overcome some problems from single-point measurement, especially when using Taylor’s frozen-turbulence hypothesis. Some structural information of optical turbulence not only makes the theory of scalar field more abundant, but also in favor of some problems about optical propagation.","PeriodicalId":225534,"journal":{"name":"Photoelectronic Technology Committee Conferences","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122155174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interaction of pulsed laser energy with bow shock in Mach 5 flow","authors":"D. Wang, Q. Li, J. Zhang","doi":"10.1117/12.2182137","DOIUrl":"https://doi.org/10.1117/12.2182137","url":null,"abstract":"Pressure sensing and schlieren imaging with high resolution and sensitivity were applied to the study of the interaction of pulsed laser energy with bow shock at Mach 5. A Nd:YAG laser operated at 1.06μm, 100mJ pulse energy was used to breakdown the hypersonic flow in shock tunnel. 3 dimensional Navier-Stokes equations were solved with upwind format to simulate the interaction. Stagnation pressure of the blunt body was measured and calculated to examine the pressure variations during the interaction. Schlieren imaging was used in conjunction with the calculated density gradients to examine the process of the interaction. Results showed that the experimental stagnation pressure and schlieren imaging fitted well with the simulation. Stagnation pressure would increase when the transmission shock approached to the blunt body and decrease with the reflection of the transmission shock. Bow shock was deformed during the interaction. Schlieren imaging supplied important phenomenon to investigate mechanism of the interaction.","PeriodicalId":225534,"journal":{"name":"Photoelectronic Technology Committee Conferences","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126933417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}