2010
2010
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Record 1 of
Title:The global image of the Moon obtained by the Chang'E-1: Data processing and lunar cartography
Author(s):Li, Chun Lai(1); Liu, Jian Jun(1); Ren, Xin(1); Mou, Ling Li(1); Zou, Yong Liao(1); Zhang, Hong Bo(1); Lü, Chang(1); Liu, Jian Zhong(1); Zuo, Wei(1); Su, Yan(1); Wen, Wei Bin(1); Bian, Wei(1); Zhao, Bao Chang(2); Yang, Jian Feng(2); Zou, Xiao Duan(1); Wang, Min(1); Xu, Chun(1); Kong, De Qing(1); Wang, Xiao Qian(1); Wang, Fang(1); Geng, Liang(1); Zhang, Zhou Bin(1); Zheng, Lei(1); Zhu, Xin Ying(1); Li, Jun Duo(1); Ouyang, Zi Yuan(1)Source: Science China Earth Sciences Volume: 53 Issue: 8 DOI: 10.1007/s11430-010-4016-x Published: 2010Abstract:The global lunar image of the first phase of Chinese Lunar Exploration Program is the first image that covered all over the surface of the Moon. It will serve as a critical foundation for succeeding exploration and scientific research. In this paper, the acquisition, characteristics, and data quality of Chang'E-1 CCD image data are described in detail. Also described are the methodology and procedure of data processing. According to rule of planetary cartography, the image data have been processed, geometrically corrected, and then mosaicked and merged in a scale of 1:2.5 million. The results of data processing and charting show that the image data of Chang'E-1 CCD and their geometric precision meet the demand of charting a map in the scale of 1:2.5 million. The relative geometric positioning precision of the global image is better than 240 m, and the absolute geometric positioning precision is slightly better than that of the ULCN2005 and Clementine lunar basemap (V2.0). The plane positioning precision is approximately 100-1500 m. This global image proves to be the best global image of the Moon so far in terms of space coverage, image quality, and positioning precision. ? 2010 Science China Press and Springer-Verlag Berlin Heidelberg.Accession Number: 20103213134243 -
Record 2 of
Title:Second-harmonic generation from a periodic array of noncentrosymmetric nanoholes
Author(s):Zhou, Renlong(1,2); Lu, Hua(2); Liu, Xueming(2); Gong, Yongkang(2); Mao, Dong(2)Source: Journal of the Optical Society of America B: Optical Physics Volume: 27 Issue: 11 DOI: 10.1364/JOSAB.27.002405 Published: November 2010Abstract:Second-harmonic generation (SHG) through a proposed thin gold film with a periodic array of subwavelength nanoholes is numerically investigated. By using a recently developed microscopic classical theory and a fullvectorial three-dimensional finite-difference time-domain method, we demonstrate that the mirror symmetry of nanoholes in one direction restricts the polarization state of second-harmonic emission in the same direction. Numerical results show that the second-order nonlinear susceptibility x(2)yyy dominates in the process of SHG when the nanoholes possess mirror symmetry in the x-axis direction. It is also found that the surface plasmon resonance can result in the enhancement of SHG from metallic nanoholes. ? 2010 Optical Society of America.Accession Number: 20104613383180 -
Record 3 of
Title:Simulation and optimization of spatial light modulation of twisted-nematic liquid crystal display
Author(s):Ma, Baiheng(1,2); Yao, Baoli(1); Yan, Shaohui(1); Peng, Fei(1,2); Min, Junwei(1,2); Lei, Ming(1,2); Ye, Tong(1)Source: Chinese Optics Letters Volume: 8 Issue: 10 DOI: 10.3788/COL20100810.0960 Published: October 2010Abstract:The approaches to obtaining desired intensity or phase modulation by twisted-nematic liquid crystal dis- play (TN-LCD) have been extensively studied based on the knowledge of the LCD's internal structure parameters. Generally, the TN-LCD placed between two linear polarizers (P) produces coupled inten- sity and phase modulation. To obtain the commonly used phase-only modulation, quarter wave plates (QWPs) are often used in front of and/or behind the LCD. Here we present a method to optimize the optical modulation properties of the TN-LCD to obtain phase-only modulation in the configuration of P-QWP-LCD-QWP-P each with proper orientation. Our method is based on the macroscopical Jones matrix descriptions for the LCD, the QWPs, and the linear polarizers. Through Jones matrix calculations, the orientations of the polarizers and QWPs can be optimized to satisfy differently desired modulation demands. In contrast to the traditional method, which requires knowledge of the LCD's internal structure parameters, our method simplified the complicated theory analysis and can work in the absence of infor- mation on the LCD's internal structure parameters, which are usually not available for the commercial products. ? 2010 Chinese Optics Letters.Accession Number: 20104713408860 -
Record 4 of
Title:Detection efficiency for an ultraviolet photon counting imaging system based on the Ge induction readout
Author(s):Zhang, Xinghua(1); Zhao, Baosheng(2); Liu, Yong'An(2); Zhao, Feifei(2); Yan, Qiurong(2)Source: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment Volume: 622 Issue: 1 DOI: 10.1016/j.nima.2010.03.140 Published: October 1, 2010Abstract:The detection efficiency, assumed proportional to the count rate, of an ultraviolet photon counting imaging system based on the Ge induction readout is studied. For the Ge induction readout, the system count rate with different Ge layer resistances, Ge layer thicknesses and ceramic thicknesses are tested under different light intensities. The test results show that the system count rate with a high resistance in the Ge layer is lower than that with a low resistance in the Ge layer; further, the imaging area decreases as the Ge layer resistance increases under high photon flux. Moreover the system count rate with a thick Ge layer is lower than that with a thin Ge layer. In addition, the system count rate with 2-mm ceramic is higher than that with 1.5- and 3-mm ceramic. The above observation should be considered when designing an ultraviolet photon counting imaging detector based on the Ge induction readout. ? 2010 Elsevier B.V.Accession Number: 20103713230143 -
Record 5 of
Title:A new quality metric for compressed images based on DDCT
Author(s):Lu, Wen(1); Li, Jing(1); Tao, Dacheng(2); Gao, Xinbo(1); Li, Xuelong(3)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 7744 Issue: DOI: 10.1117/12.862432 Published: 2010Abstract:As the performance-indicator of the image processing algorithms or systems, image quality assessment (IQA) has attracted the attention of many researchers. Aiming to the widely used compression standards, JPEG and JPEG2000, we propose a new no reference (NR) metric for compressed images to do IQA. This metric exploits the causes of distortion by JPEG and JPEG2000, employs the directional discrete cosine transform (DDCT) to obtain the detail and direction information of the images and incorporates with the visual perception to obtain the image quality index. Experimental results show that the proposed metric not only has outstanding performance on JPEG and JPEG2000 images, but also applicable to other types of artifacts. ? 2010 SPIE.Accession Number: 20104913467526 -
Record 6 of
Title:An image quality assessment metric with no reference using hidden Markov tree model
Author(s):Gao, Fei(1); Gao, Xinbo(1); Lu, Wen(1); Tao, Dacheng(2); Li, Xuelong(3)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 7744 Issue: DOI: 10.1117/12.862433 Published: 2010Abstract:No reference (NR) method is the most difficult issue of image quality assessment (IQA), which does not need the original image or its features as reference and only depends on the statistical law of the natural images. So, the NR-IQA is a high-level evaluation for image quality and simulates the complicated subjective process of human beings. This paper presents a NR-IQA metric based on Hidden Markov Tree (HMT) model. First, the HMT is utilized to model natural images, and the statistical properties of the model parameters are analyzed to mimic variation of image degradation. Then, by estimating the deviation degree of the parameters from the statistical law the distortion metric is constructed. Experimental results show that the proposed image quality assessment model is consistent well with the subjective evaluation results, and outperforms the existing models on difference distortions. ? 2010 SPIE.Accession Number: 20104913467611 -
Record 7 of
Title:Local histogram based geometric invariant image watermarking
Author(s):Deng, Cheng(1); Gao, Xinbo(1); Li, Xuelong(2); Tao, Dacheng(3)Source: Signal Processing Volume: 90 Issue: 12 DOI: 10.1016/j.sigpro.2010.05.032 Published: December 2010Abstract:Compared with other existing methods, the feature point-based image watermarking schemes can resist to global geometric attacks and local geometric attacks, especially cropping and random bending attacks (RBAs), by binding watermark synchronization with salient image characteristics. However, the watermark detection rate remains low in the current feature point-based watermarking schemes. The main reason is that both of feature point extraction and watermark embedding are more or less related to the pixel position, which is seriously distorted by the interpolation error and the shift problem during geometric attacks. In view of these facts, this paper proposes a geometrically robust image watermarking scheme based on local histogram. Our scheme mainly consists of three components: (1) feature points extraction and local circular regions (LCRs) construction are conducted by using Harris-Laplace detector; (2) a mechanism of grapy theoretical clustering-based feature selection is used to choose a set of non-overlapped LCRs, then geometrically invariant LCRs are completely formed through dominant orientation normalization; and (3) the histogram and mean statistically independent of the pixel position are calculated over the selected LCRs and utilized to embed watermarks. Experimental results demonstrate that the proposed scheme can provide sufficient robustness against geometric attacks as well as common image processing operations. ? 2010 Elsevier B.V. All rights reserved.Accession Number: 20103213144003 -
Record 8 of
Title:Image quality assessment and human visual system
Author(s):Gao, Xinbo(1); Lu, Wen(1); Tao, Dacheng(2); Li, Xuelong(3)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 7744 Issue: DOI: 10.1117/12.862431 Published: 2010Abstract:This paper summaries the state-of-the-art of image quality assessment (IQA) and human visual system (HVS). IQA provides an objective index or real value to measure the quality of the specified image. Since human beings are the ultimate receivers of visual information in practical applications, the most reliable IQA is to build a computational model to mimic the HVS. According to the properties and cognitive mechanism of the HVS, the available HVS-based IQA methods can be divided into two categories, i.e., bionics methods and engineering methods. This paper briefly introduces the basic theories and development histories of the above two kinds of HVS-based IQA methods. Finally, some promising research issues are pointed out in the end of the paper. ? 2010 SPIE.Accession Number: 20104913467549 -
Record 9 of
Title:Cellulose acetate polymer film modified microstructured polymer optical fiber towards a nitrite optical probe
Author(s):Li, Dongdong(1,2); Wang, Lili(1)Source: Optics Communications Volume: 283 Issue: 14 DOI: 10.1016/j.optcom.2010.04.005 Published: July 15, 2010Abstract:A novel microstructured polymer optical fiber (MPOF) probe for nitrites (NO2-) detection was made by forming rhodamine 6G (Rh 6G)-doped cellulose acetate (CA) on the side wall of array holes in a MPOF. It was found that the MPOF probe only have a response to nitrites in a certain concentration of sulfuric acid solution. The calibration graph of fluorescence intensity versus nitrites concentration was linear in the range of 2.0 ×10-4 g/ml-5.0×10-3 g/ml. The method possesses ease of chemical modification, low cost design, and potential for direct integration with existing instrumentation, and has been applied to the determination of nitrites in real samples with satisfactory results. ? 2010 Elsevier B.V. All rights reserved.Accession Number: 20110413620061 -
Record 10 of
Title:Ultracompact wave plates by air holes periodic dielectric waveguides
Author(s):Zhang, Wenfu(1,2); Liu, Jihong(3); Huang, Wei-Ping(4); Zhao, Wei(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 7609 Issue: DOI: 10.1117/12.845956 Published: 2010Abstract:Ultracompact wave plate (UWP) will be one of the key elements in future all-optical photonic integrated circuits (PICs). In this paper, we propose UWPs based on periodic dielectric waveguides (PDWs) with air holes in conventional dielectric waveguides. The mode characteristics (for both TE and TM) and birefringence of PDWs are calculated by plane wave method (PWM). The transmission efficiencies and phase changing of TE and TM waves in PDW are obtained by finite-difference time-domain (FDTD) scheme. Based on the PDWs, the quarter-wave plates (QWPs) and half-wave plates (HWPs) are designed. Calculating results show that the proposed PDW has large birefringence (Δn>1) and can introduce 2π phase difference with a short length being less than λ. The size of low order UWPs are compact. The transmission efficiency of PDW is improved by taper structure. Based on the taper PDW, ultra-wide band (>100 nm) achromatic QWP is designed. Profiting from the waveguide guiding, the UWPs have low beam divergence and can be easily integrated with other photonic components. The UWPs have many potential applications in future PIC systems such as optical communications, optical measurements and sensors. ? 2010 Copyright SPIE - The International Society for Optical Engineering.Accession Number: 20101812912718 -
Record 11 of
Title:Total-internal-reflection fluorescence microscopy with W-shaped axicon mirrors
Author(s):Lei, Ming(1,2); Zumbusch, Andreas(1)Source: Optics Letters Volume: 35 Issue: 23 DOI: 10.1364/OL.35.004057 Published: December 1, 2010Abstract:A scheme based on a W-shaped axicon mirror device for total-internal- reflection fluorescence microscopy (TIRFM) is presented. This approach combines the advantages of higher efficiency compared with traditional TIRFM, adjustable illumination area, and simple switching between wide-field and TIRF imaging modes. TIRF images obtained with this approach are free of shadow artifacts and of interference fringes. Example micrographs of fluorescently labeled polystyrene beads, of Convallaria majalis tissue, and of Propidium-iodide- labeled Chinese hamster ovary cells are shown, and the capabilities of the scheme are discussed. ? 2010 Optical Society of America.Accession Number: 20110113554963 -
Record 12 of
Title:Fluorescence hydrogen peroxide probe based on a microstructured polymer optical fiber modified with a titanium dioxide film
Author(s):Li, Dongdong(1,2); Wang, Lili(1)Source: Applied Spectroscopy Volume: 64 Issue: 5 DOI: 10.1366/000370210791211709 Published: May 2010Abstract:A highly sensitive microstructured polymer optical fiber (MPOF) probe for hydrogen peroxide was made by forming a rhodamine 6G-doped titanium dioxide film on the side walls of array holes in an MPOF. It was found that hydrogen peroxide only has a response to the MPOF probe in a certain concentration of potassium iodide in sulfuric acid solution. The calibration graph of fluorescence intensity versus hydrogen peroxide concentration is linear in the range of 1.6 × 10-7 mol/L to 9.6 × 10-5 mol/L. The method, with high sensitivity and a wide linear range, has been applied to the determination of trace amounts of hydrogen peroxide in a few real samples, such as rain water and contact lens disinfectant, with satisfactory results. ? 2010 Society for Applied Spectroscopy.Accession Number: 20102212962495