2016
2016
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Record 301 of
Title:Research on manufacturing method of CGH
Author(s):Duan, Xueting(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 9684 Issue: DOI: 10.1117/12.2244164 Published: 2016Abstract:Computer Generated Holograms (CGH) has shown strong application potential and broad application prospect as the more and more extensive application of CGH. With respect to manufacture an available CGH, design the CGH will be easier. Therefore, this paper mainly summarizes some current feasible CGH manufacturing processes, and in this paper, the manufacturing processes of different types of CGH are presented and analyzed. ? 2016 SPIE.Accession Number: 20165003113924 -
Record 302 of
Title:Motion Blur Detection with an Indicator Function for Surveillance Machines
Author(s):Pang, Yanwei(1); Zhu, Hailong(1); Li, Xuelong(2); Pan, Jing(1,3)Source: IEEE Transactions on Industrial Electronics Volume: 63 Issue: 9 DOI: 10.1109/TIE.2016.2564938 Published: September 2016Abstract:Motion is an important clue for industrial inspection, video surveillance, and service machines to localize and recognize products and objects. Because blur co-occurs with motion, it is desirable for developing efficient and robust motion blur detection algorithm. However, existing algorithms are inefficient for detecting spatially varying motion blur. To deal with the problem, this paper presents a theorem, according to which, motion blur can be efficiently detected and segmented. According to the theorem, the proposed algorithm requires a simple filtering operation and variance computation. Classification as either blurred or unblurred pixel can be done by substituting the variance into the proposed simple formula and checking the sign of the resulting value. Moreover, a geometric interpretation and two extensions of the algorithm are given. Importantly, based on the geometric interpretation of the indicator function, we develop a one-class classifier, which is more effective than the indicator function and has comparable computational cost of the indicator function. Experimental results on detecting motion-blurred cars, motorcycles, bicycles, bags, and persons demonstrate that the proposed algorithm is very efficient without loss of effectiveness. ? 1982-2012 IEEE.Accession Number: 20163402731812 -
Record 303 of
Title:61 nm generation from a tilted fiber grating based all-fiber mode locked Erbium doped laser
Author(s):Wang, Tianxing(1); Yan, Zhijun(2); Mou, Chengbo(1); Zhou, Kaiming(3); Zhang, Lin(3); Wang, Tingyun(1)Source: Optics InfoBase Conference Papers Volume: Issue: DOI: 10.1364/BGPP.2016.BM3B.6 Published: August 29, 2016Abstract:By incorporating a tilted fiber grating in a dispersion managed fiber laser cavity, we have achieved ultrashort pulse generation with a flat spectral width of 61 nm from an all-fiber mode locked Erbium doped laser. ? OSA 2016.Accession Number: 20171303506527 -
Record 304 of
Title:Stability of phase compensator in near-infrared polarized interferometer
Author(s):Xie, Zheng-Mao(1); Qi, Wen-Bo(1); Wu, Guo-Jun(1); He, Jun-Hua(1)Source: Guangzi Xuebao/Acta Photonica Sinica Volume: 45 Issue: 9 DOI: 10.3788/gzxb20164509.0923003 Published: September 1, 2016Abstract:Phase compensator is a key element in the polarized interferometer, whose stability has a directive influence on the reliability of the polarized interference spectroscopy. The specification of the phase compensator such as the relative sensitivity of optical path difference, the tilted error tolerance of optical wedge, the oblique incidence angle error tolerance and the temperature adaptability were studied, and the corresponding calculated formulas were derived. The anti-interference ability of the moving optical wedge is 2/Δnsinθ times stronger than the classical Michelson interferometer. The ability of the moving wedge to resist the inclination is 1.75/Δn times higher than classic Michelson interferometer. After light's incidence with small angle, there are no additional optical path. The greatest optical path distance error of the phase compensator is 1.8 μm when the temperature changes from -20℃ to 85℃, which has a good thermal stability. The angle of the wedge is also an important parameter to affect the phase compensator. If setting the angle of the wedge as 30°, a good balance between performance, size and cost may be achieved. The birefringence difference of crystal material is smaller than one, so the stability advantages of the polarized interferometer are very obvious which build up a good basis for its field application with complicated surroundings. ? 2016, Science Press. All right reserved.Accession Number: 20163802821810 -
Record 305 of
Title:The development of high precision carbon fiber composite mirror
Author(s):Xu, Liang(1); Ding, Jiao-Teng(1); Wang, Yong-Jie(1); Xie, Yong-Jie(1); Ma, Zhen(1); Fan, Xue-Wu(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 9683 Issue: DOI: 10.1117/12.2243736 Published: 2016Abstract:Due to low density, high stiffness, low thermal expansion coefficient, duplicate molding, etc., carbon fiber reinforced polymer (CFRP) is one of the potential materials of the optical mirror. The process developed for Φ300mm high precision CFRP mirror described in this paper. A placement tool used to improve laying accuracy up to ± 0.1°.A special reinforced cell structure designed to increase rigidity and thermal stability. Optical replication process adopted for surface modification of the carbon fiber composite mirror blank. Finally, surface accuracy RMS of Φ300mm CFRP mirror is 0.22μm, surface roughness Ra is about 2nm, and the thermal stability can achieve 13nm /°C from the test result. The research content is of some reference value in the infrared as well as visible light applications. ? 2016 SPIE.Accession Number: 20164903096460 -
Record 306 of
Title:Measurement system of large-scale sleeve roundness error
Author(s):Liu, Jie(1); Li, Hua(1); Fu, Xihong(1)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 45 Issue: 1 DOI: 10.3788/IRLA201645.0117005 Published: January 25, 2016Abstract:In order to evaluate the roundness error of large-scale sleeve, a roundness error measurement system of large-scale sleeve was established and its applied algorithms such as laser collimation, image processing and etc were investigated. First, the method that the system obtained roundness error of large- scale sleeve was introduced. Then, based on the measuring process, a filtering algorithm of minimum circumscribed circle which analyzed the point position forms was presented. Finally, filtering efficiency was analyzed. Computing time and the precision were compared with the similar algorithm. Experimental results indicate that the computing time of the filtering algorithm is shorter by more than 30% and the precision of the CCD measurement rod is 0.7 mm. The roundness error measurement system of large-scale sleeve can satisfy the requirement of the project and evaluate roundness error effectively. ? 2016, Editorial Board of Journal of Infrared and Laser Engineering. All right reserved.Accession Number: 20160902037338 -
Record 307 of
Title:Design and fabrication of CGH for 600mm diameter SiC primary mirror surface figure testing
Author(s):Pang, Zhihai(1); Ma, Zhen(1); Fan, Xuewu(1); Zou, Gangyi(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 9684 Issue: DOI: 10.1117/12.2243443 Published: 2016Abstract:Computer-generated hologram (CGH) is an effective way to compensate wavefront aberration in null test of aspheric surfaces and freeform surfaces. Our strategies of CGH design for 600mm diameter SiC primary mirror surface figure testing are presented, and an experiment demonstrating the compensation test results of CGH is reported. We design a CGH including two sections on the same substrate in order to align the CGH to the incident wavefront: main section for compensating wavefront in null test, alignment section for adjusting the relative position between CGH and interferometer. In order to isolate different orders of diffraction, we used power carrier to make different orders of diffraction come to focus at different position along the axis to avoid ghost reflections. We measured the 600mm diameter SiC primary mirror using this CGH, and the surface test result is 0.033 rms. ? 2016 SPIE.Accession Number: 20165003113947 -
Record 308 of
Title:Misalignment induced aberration off-axis optical system
Author(s):Pang, Zhihai(1); Fan, Xuewu(1); Ma, Zhen(1); Zou, Gangyi(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 9682 Issue: DOI: 10.1117/12.2243446 Published: 2016Abstract:Through introducing transformed pupil vector and shifted center of aberration fields vector into the nodal aberration expansions of an axially symmetric optical system, the aberration expression in third order of an off-axis optical system and misaligned off-axis optical system are detailed. Nodal aberration characteristics of misaligned off-axis optical system are revealed only by analyzing the pupil decentration vector, aberration fields shifted vector and the aberration coefficients of the axially symmetric optical system. Actually, it is well demonstrated that the 3rd spherical aberration, 3rd coma, 3rd astigmatism in a misalignment off-axis system are comparable to the aberrations in a misalignment axially symmetric system. Otherwise it will not only induced constant 3rd spherical aberration but also constant 3rd coma and 3rd astigmatism over the field of view, when aligned an off-axis optical system elements with error axial spacing. ? 2016 SPIE.Accession Number: 20164903095170 -
Record 309 of
Title:Annular force based on variable curvature mirror technique
Author(s):Xie, Xiao-Peng(1); Zhao, Hui(1); Li, Chuang(1); Fan, Xue-Wu(1); Ren, Guo-Rui(1); Chai, Wen-Yi(1); Xu, Liang(1); Su, Yu(1)Source: Guangzi Xuebao/Acta Photonica Sinica Volume: 45 Issue: 8 DOI: 10.3788/gzxb20164508.0822001 Published: August 1, 2016Abstract:Based on the elasticity theory of thin plates, the basic analysis on annular line load model and deflection equations based on this model was given. Aiming to generate a large saggitus variation using a smaller force, mathematical analysis on different mirror thickness and actuate ring radius was done by using MATLAB, the corresponding optimal value is 2~4 mm and 1/2 mirror's clear radius. One QeB variable curvature mirror prototype, whose diameter and thickness is 100 mm and 3 mm respectively was designed, fabricated and the whole structure's first ten vibration mode analysis was given. The surface accuracy of the assembled prototype is nearly λ/30. Finally, the capability in altering curvature and maintaining surface figure accuracy was tested experimentally. By improving the variable curvature mirror structure, the QeB variable curvature mirror could provide a saggitus more than 30 wavelengths(632.8 nm) and the degradation of surface figure accuracy is weakly correlated to the variation of radius of curvature. ? 2016, Science Press. All right reserved.Accession Number: 20163402737294 -
Record 310 of
Title:Relevance and irrelevance graph based marginal Fisher analysis for image search reranking
Author(s):Ji, Zhong(1); Pang, Yanwei(1); Yuan, Yuan(2); Pan, Jing(3)Source: Signal Processing Volume: 121 Issue: DOI: 10.1016/j.sigpro.2015.11.010 Published: April 2016Abstract:Learning-to-rank techniques have shown promising results in the domain of image ranking recently, where dimensionality reduction is a critical step to overcome the "curse of dimensionality". However, conventional dimensionality reduction approaches cannot guarantee the satisfying performance because the important ranking information is ignored. This paper presents a novel "Ranking Dimensionality Reduction" scheme specifically designed for learning-to-rank based image ranking, which aims at not only discovering the intrinsic structure of data but also keeping the ordinal information. Within this scheme, a new dimensionality reduction algorithm called Relevance Marginal Fisher Analysis (RMFA) is proposed. RMFA models the proposed pairwise constraints of relevance-link and irrelevance-link into the relevance graph and the irrelevance graph, and applies the graphs to build the objective function with the idea of Marginal Fisher Analysis (MFA). Further, a semi-supervised RMFA algorithm called Semi-RMFA is developed to offer a more general solution for the real-world application. Extensive experiments are carried on two popular, real-world image search reranking datasets. The promising results demonstrate the robustness and effectiveness of the proposed scheme and methods. ? 2015 Elsevier B.V.Accession Number: 20155101708486 -
Record 311 of
Title:New Water Vapor Barrier Film Based on Lamellar Aliphatic-Monoamine-Bridged Polysilsesquioxane
Author(s):Zhang, Cong(1,4); Zhang, Ce(1,4); Ding, Ruimin(1); Cui, Xinmin(1,4); Wang, Jing(1,4); Zhang, Qinghua(3); Xu, Yao(2)Source: ACS Applied Materials and Interfaces Volume: 8 Issue: 23 DOI: 10.1021/acsami.6b00878 Published: June 15, 2016Abstract:Siloxane-based hybrid lamellar materials with ordered nanostructure units paralleling to the substrate have been widely used for water vapor barrier. However, it is very difficult to control the orientation of the lamellar units at molecular level. In this Research Article, a new lamellar bridged polysilsesquioxane (BPSQ) film, whose voids between lamellae were filled by pendant alkyl chains in the organic bridge, was prepared via the stoichiometric reaction between 3-glycidoxypropyltrimethoxysilane and aliphatic monoamine at 60 °C without catalyst. Experimental evidence obtained from FT-IR, MS, NMR, and GIXRD techniques suggested that the as-prepared BPSQ films were constructed by lamellar units with disordered orientation. Nonetheless, they possessed satisfactory water vapor barrier performance for potassium dihydrogen phosphate (KDP) and deuterated potassium dihydrogen phosphate (DKDP) optical crystals, and the water vapor transmission rate through BPSQ film with thickness of 25 μm was as low as 20.3 g·m-2·d-1. Those results proved that filling the voids between molecular lamellae with alkyl chains greatly weakened the effect of lamellar unit orientation on the vapor barrier property of BPSQ film. ? 2016 American Chemical Society.Accession Number: 20162602533555 -
Record 312 of
Title:Thermochromic VO2 films from ammonium citrato-oxovanadate(IV) with excellent optical and phase transition properties
Author(s):Zhang, Jing(1,2); Tian, Hong(1); Hao, Liang(3); Jin, Xin(4); Yang, Chunming(4); Wang, Jing(1,2); Cui, Xinmin(1,2); Wang, Conghui(1,2); Zhang, Ce(1,2); Zhang, Cong(1,2); Xu, Yao(5)Source: Journal of Materials Chemistry C Volume: 4 Issue: 23 DOI: 10.1039/c6tc00315j Published: 2016Abstract:Thermochromic VO2 film is a potential material for energy-saving windows in future buildings. Considering the difficulty in controlling the valence state and polymorphism during the formation of VO2 (M) film, we propose a facile and safe solution method of fabricating monoclinic (M) VO2 film directly from the newly synthesized ammonium citrato-oxovanadate(iv) compound [(NH4)4[V2O2(C6H4O7)2]·2H2O, denoted as CA-V(iv)], as a vanadium(iv) precursor to stabilize vanadium in the 4+ valence state without utilizing V2O5 as an intermediate or complex post-treatment in vacuum. This new ambient-stable compound CA-V(iv) contains centrosymmetric dinuclear complex anions [{VO(C6H4O7)}2]4-, in which the carboxylate groups are coordinated to the V4+ ions in a monodentate fashion and each vanadium atom exhibits distorted octahedral geometry. With a perfect monoclinic phase, the VO2 films possessed excellent thermochromic and visible transmissive properties. Accompanying a change in film thickness from 119 nm to 41 nm, the integral visible transmittance Tvis at 25 °C of VO2 films ranged from 38.4% to 70.0%. The maximum visible transmittance (Tmax) reached 77.2% for VO2 film with a thickness of 41 nm, which shows that the phase transition of VO2 did not greatly affect the visible transmittance of the film. For the VO2 film with a thickness of 41 nm, of which the visible transmittance modulation (ΔTvis = 2.1%) was the largest among the three samples, the solar energy modulation (ΔTsol) reached 11.3%. Moreover, the transition temperature of our VO2 films was far below that of bulk VO2 (68 °C), and the best transition temperature was as low as 50.8 °C. ? 2016 The Royal Society of Chemistry.Accession Number: 20162502512314