2013
2013
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Record 193 of
Title:Design of a large plane CMOS camera system FPGA
Author(s):Liu, Meiying(1); Wang, Hu(1); Wen, Desheng(1); Liu, Jie(1); Liu, Yang(1); Xue, Yaoke(1); Yang, Shaodong(1)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 42 Issue: SUPPL.2 DOI: Published: December 2013Abstract:For achieving the high resolution real-time processing of the digital image, using high-performance CMOS image sensor LUPA-4000 produced by CYPRESS company as the key component, a kind of large plane CMOS camera system was designed, based on FPGA and serial communication controller. The overall structure and circuit design were described. Combined with the CMOS image sensor's timing sequence and working mode, the sensor driving circuit and image data memory circuit were implemented with FPGA. Experiments demonstrated that the designed camera system was reasonable. The whole system run steadily and reliably. The communication with computer was exact. Image with high quality had been taken after installing optical system, and the resolution of the image could be achieved 2048×2048 pixels.Accession Number: 20140317216003 -
Record 194 of
Title:An improved method based on fast bilateral filter for high dynamic image rendering
Author(s):Zhang, Hui(1); Wang, Hua(1); Cao, Jian Zhong(1); Zhao, Xiao Dong(1); Lei, Yang Jie(1); Liu, Guang Sen(1)Source: Advanced Materials Research Volume: 710 Issue: DOI: 10.4028/www.scientific.net/AMR.710.665 Published: 2013Abstract:This paper presents an improved high dynamic range image tone mapping method based on fast bilateral filtering. The algorithm first applied a bilateral filtering to the luminance channel of the image, the image is decomposed into an HDR base layer and an LDR detail layer. Then the HDR base layer is blurred with bilateral filtering again, get the details portion of the base layer, at the same time the dynamic range of the global base layer is compressed. Finally, the detail component and the compressed HDR base layer are recombined and the result is tone-mapped image for displaying. For color image, the color restoration converts luminance value into RGB color. Experimental results show that the proposed technique performed better than the conventional bilateral filtering, preserving more details and enhancing local contrast, giving decent visual effect and avoiding additional artifacts. ? (2013) Trans Tech Publications, Switzerland.Accession Number: 20133016530690 -
Record 195 of
Title:Synthesis and strong near-infrared fluorescence of LiLa 1-xNdx(PO3)4 nanocrystals with high doping concentrations
Author(s):Wang, Zhongyue(1); Cui, Xiaoxia(3); Zheng, Ruilin(2); Duan, Weikuan(1); Peng, Bo(1,3); Wei, Wei(2,3)Source: Nanoscale Volume: 5 Issue: 21 DOI: 10.1039/c3nr03367h Published: November 7, 2013Abstract:A series of LiLa1-xNdx(PO3)4 (LLNP) nanocrystals are synthesized by a combustion method for the first time. With irregular short-rod shapes and an average size of about 70 nm, the LiLa1-xNdx(PO3)4 nanocrystals exhibit stronger fluorescence emission of 1.8-6.5 times in the doping concentration range of 1 mol% to 100 mol% than Nd3+ (2.5 wt%) doped phosphate glass, and have a long lifetime of 122 μs for the fully doped nanocrystals. Moreover, the LiLa1-xNdx(PO 3)4 nanocrystals show the lowest lifetime decay rate of 5.09 μs per mol% and a quenching ratio of 10.81%. Considering the above outstanding performances, LiLa1-xNdx(PO3) 4 nanocrystals may have promising applications in optical amplifiers and lasers. ? 2013 The Royal Society of Chemistry.Accession Number: 20134316877170 -
Record 196 of
Title:Single image super-resolution with multiscale similarity learning
Author(s):Zhang, Kaibing(1); Gao, Xinbo(2); Tao, Dacheng(3); Li, Xuelong(4)Source: IEEE Transactions on Neural Networks and Learning Systems Volume: 24 Issue: 10 DOI: 10.1109/TNNLS.2013.2262001 Published: 2013Abstract:Example learning-based image super-resolution (SR) is recognized as an effective way to produce a high-resolution (HR) image with the help of an external training set. The effectiveness of learning-based SR methods, however, depends highly upon the consistency between the supporting training set and low-resolution (LR) images to be handled. To reduce the adverse effect brought by incompatible high-frequency details in the training set, we propose a single image SR approach by learning multiscale self-similarities from an LR image itself. The proposed SR approach is based upon an observation that small patches in natural images tend to redundantly repeat themselves many times both within the same scale and across different scales. To synthesize the missing details, we establish the HR-LR patch pairs using the initial LR input and its down-sampled version to capture the similarities across different scales and utilize the neighbor embedding algorithm to estimate the relationship between the LR and HR image pairs. To fully exploit the similarities across various scales inside the input LR image, we accumulate the previous resultant images as training examples for the subsequent reconstruction processes and adopt a gradual magnification scheme to upscale the LR input to the desired size step by step. In addition, to preserve sharper edges and suppress aliasing artifacts, we further apply the nonlocal means method to learn the similarity within the same scale and formulate a nonlocal prior regularization term to well pose SR estimation under a reconstruction-based SR framework. Experimental results demonstrate that the proposed method can produce compelling SR recovery both quantitatively and perceptually in comparison with other state-of-the-art baselines. ? 2013 IEEE.Accession Number: 20134216849774 -
Record 197 of
Title:Impact of three-axis error on angle measurement of photoelectric theodolite
Author(s):Tian, Liude(1); Liu, Chaohui(1); Zhao, Jianke(1); Pan, Liang(1); Duan, Yaxuan(1); Zhang, Zhoufeng(1)Source: Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering Volume: 42 Issue: SUPPL.1 DOI: Published: 2013Abstract:Shafting is the key module of photoelectric theodolite to decide the measurement precision, three-axis error is the main factor affecting the accuracy of photoelectric theodolite angle measuring. According to the three axis horizontal structure, the spherical coordinate system was set up and the accurate mathematical model of the measurement error caused by shafting error was deduced using spherical trigonometry knowledge. The simplified model suitable for engineering application was obtained by simplifying the accurate model. The simulation results show that collimation error and horizontal axis tilt have great effect on azimuth angle measuring, the larger target pitch angle is, the more serious the effect is. However, collimation error and horizontal axis tilt has little influence on pitch angle measuring, and the influence can be neglected. The effect of vertical axis tilt error on azimuth angle and elevation angle measuring is the sine function of target azimuth. The influence of vertical axis tilt on azimuth angle and elevation angle measuring is the sine function of the target azimuth. It can provide an effective method to analyze accuracy, distribute and correct error of the photoelectric theodolite.Accession Number: 20134416940648 -
Record 198 of
Title:New scene-based adaptive bad pixel detection algorithm for IRFPA
Author(s):Leng, Han-Bing(1); Zhou, Zuo-Feng(1); Liu, Wei(1); Yi, Bo(1); Xie, Qing-Sheng(1); Wu, Deng-Shan(1); Cao, Jian-Zhong(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 8907 Issue: DOI: 10.1117/12.2033162 Published: 2013Abstract:Traditional bad pixel detection algorithm is always based on the radiometric calibration. This method is easy to operate, but only suitable for the bad pixels whose positions are fixed. During the longtime operation period, environment temperature usually has drastic influence on IRFPA, the number of bad pixels often increase and their positions also vary, this result in the degradation of infrared image quality. In this paper, a new scene-based adaptive bad pixel detection algorithm is proposed for IRFPA. The algorithm firstly comparing the pixel value with its neighborhood, and affirm bad pixels preliminary through a suitable threshold. Then the potential bad pixels from different scene are matched, false bad pixels caused by scene and targets are eliminated, real bad pixels are confirmed. The essence of the proposed algorithm is using the correlation between the pixel and its neighborhood. The bad pixels and some targets in the scene have a weak correlation within neighborhoods, and the position of bad pixels varies slowly while the scene varies drastically when IRFPA is in use. This new method can be implemented in hardware easily and achieve the real time demand. With the real infrared images obtained from a camera, the experiment results show the effectiveness of the proposed algorithm. ? 2013 Copyright SPIE.Accession Number: 20141317510156 -
Record 199 of
Title:A new algorithm of inter-frame filtering in IR image based on threshold value
Author(s):Liu, Wei(1); Leng, Hanbing(1); Chen, Weining(1); Yang, Hongtao(1); Xie, Qingsheng(1); Yi, Bo(1); Zhang, Haifeng(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 8907 Issue: DOI: 10.1117/12.2033067 Published: 2013Abstract:This paper proposed a new algorithm of inter-frame filtering in IR image based on threshold value for the purpose of solving image blur and smear brought by traditional inter-frame filtering algorithm. At first, it finds out causes of image blur and smear by analyzing general inter-frame filtering algorithm and dynamic inter-frame filtering algorithm, hence to bring up a new kind of time-domain filter. In order to obtain coefficients of the filter, it firstly gets difference image of present image and previous image, and then, it gets noisy threshold value by analyzing difference image with probability analysis method. The relationship between difference image and threshold value helps obtaining the coefficients of filter. At last, inter-frame filtering method is adopted to process pixels interrupted by noise. The experimental result shows that this algorithm has successfully repressed IR image blur and smear, and NETD tested by traditional inter filtering algorithm and the new algorithm are respectively 78mK and 70mK, which shows it has a better noise reduction performance than traditional ones. The algorithm is not only applied to still image, but also to sports image. As a new algorithm with great practical value, it is easy to achieve on FPGA, of excellent real-time performance and it effectively extends application scope of time domain filtering algorithm. ? 2013 Copyright SPIE.Accession Number: 20141317510150 -
Record 200 of
Title:The design of optomechanical for bear severe mechanics environment
Author(s):Yang, Hongtao(1); Fan, Zheyuan(1); Chen, Weining(1); Zhang, Zhaohui(1); Zhang, Jian(1); Zhang, Zhi(1)Source: Key Engineering Materials Volume: 552 Issue: DOI: 10.4028/www.scientific.net/KEM.552.52 Published: 2013Abstract:Optical lenses act as the important methods for acquire the image information is applied increasingly board ,In accordance with the application environment that require content the precision and the force environment adaptation yet more power, so it is necessary that research on the adaption ability to the big level vibration and shock. In order to stand the bitter force environment put to use the centering assembly technology to ensure the image quality of the optical system. Design the different damping coefficient rubber-bearing isolation that assimilate the big level shock energy. At first, by the Pro/e software establish the three-dimensional model and use the ANSYS software simulate and analysis the result of the design. We want to apple the Sigfit software to simulate the effect that the vibration and shock affect on the MTF of the optical system. After optimize the design theory so as to attain the optimized result. By the experiment test the lenses about the accommodate ability, the result which can meet the shock of5000g.and 20g random vibration, camera can work effectively. This kind of design technology is mature and reliable and live through the examination under all kinds of environment, this design method is provided the reference for the design and development of optical mechanism production. ? (2013) Trans Tech Publications, Switzerland.Accession Number: 20133016543312 -
Record 201 of
Title:Design of a refractive/diffractive hybrid middle infrared continuous zoom optical system
Author(s):Hu, Dandan(1); Zhao, Jianke(1); Xue, Xun(1); Liu, Feng(1); Zhang, Jie(1); Xu, Liang(1)Source: Key Engineering Materials Volume: 552 Issue: DOI: 10.4028/www.scientific.net/KEM.552.33 Published: 2013Abstract:The application of diffractive surface in the continuous zoom system is investigated by taking advantage of the negative dispersion characteristics of binary elements. A sample design is presented in this paper using cool 320×240 detector with staring focal plane array and secondary imaging, and a mid-wave optical system using mechanical-compensated with refractive/diffractive hybrid technique is designed. The Pixel Dimensions of the detector is 30μm, and the wavelength between 3.7μm ～4.8μm.The system adopts negative group variable times and positive group of compensation which can realize 18mm～180mm continuous zoom and FOV =36.8°～3.8° , F-number is 2, it consists of 7 lenses including 2 aspheric surface and 1 diffractive surface. The length of this system is 230mm with the reflection mirror to shorten optical path. The results show that the modulation transfer function(MTF) is above 0.6 within the whole focal range at spatial frequency of 17 lp/mm, and Root Mean Square (RMS) value of spot diameter were smaller than the Pixel Dimensions. After the image quality being optimized, the monotonic and smooth cam curve is given and 100% cold shield efficiency is obtained. The curve shows that the imaging plane is stable and the cam is easy to process. The system has advantages of simple structure, high image quality and short zoom path etc. ? (2013) Trans Tech Publications, Switzerland.Accession Number: 20133016543309 -
Record 202 of
Title:The realization of network video monitoring system
Author(s):Hou, Zhuo-Wei(1); Qiu, Yue-Hong(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 8908 Issue: DOI: 10.1117/12.2031629 Published: 2013Abstract:The paper presents a network video monitoring system based on field programmable gate array to implement the real time acquisition and transmission of video signals. The system includes image acquisition module, central control module and Ethernet transmission module. According to request, Cyclone FPGA is taken as the control center in the system, using Quartus II and Nios II IDE as development tool to build the hardware development platform. A kind of embedded hardware system is built based on SOPC technic, in which the Nios II soft-core and other controllers are combined by configuration. Meanwhile, the μClinux is used as embedded operating system to make the process of acquisition and transmission of the data picture on the Internet more reliable. In order to fulfill the task of MAC and PHY, the fast Ethernet controller should be connected to the SOPC. TCP/IP protocol is used to implement data transmission. Based on TCP/IP protocol, the Web Servers should be embedded to implement the protocol of HTTP, TCP and UDP. Through the research of the thesis, with programmable logic device being the core and network being the transmission media, the design scheme of the video monitoring system is presented. The hardware's design is mainly done in the thesis. The principal and function of the system is deeply explained, so it can be the important technology and specific method. ? 2013 SPIE.Accession Number: 20134216857631 -
Record 203 of
Title:Adaptive bad pixel correction algorithm for IRFPA based on PCNN
Author(s):Leng, Hanbing(1); Zhou, Zuofeng(1); Cao, Jianzhong(1); Yi, Bo(1); Yan, Aqi(1); Zhang, Jian(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 8917 Issue: DOI: 10.1117/12.2032065 Published: 2013Abstract:Bad pixels and response non-uniformity are the primary obstacles when IRFPA is used in different thermal imaging systems. The bad pixels of IRFPA include fixed bad pixels and random bad pixels. The former is caused by material or manufacture defect and their positions are always fixed, the latter is caused by temperature drift and their positions are always changing. Traditional radiometric calibration-based bad pixel detection and compensation algorithm is only valid to the fixed bad pixels. Scene-based bad pixel correction algorithm is the effective way to eliminate these two kinds of bad pixels. Currently, the most used scene-based bad pixel correction algorithm is based on adaptive median filter (AMF). In this algorithm, bad pixels are regarded as image noise and then be replaced by filtered value. However, missed correction and false correction often happens when AMF is used to handle complex infrared scenes. To solve this problem, a new adaptive bad pixel correction algorithm based on pulse coupled neural networks (PCNN) is proposed. Potential bad pixels are detected by PCNN in the first step, then image sequences are used periodically to confirm the real bad pixels and exclude the false one, finally bad pixels are replaced by the filtered result. With the real infrared images obtained from a camera, the experiment results show the effectiveness of the proposed algorithm. ? 2013 SPIE.Accession Number: 20135117093592 -
Record 204 of
Title:Subwavelength multiple focal spots produced by tight focusing the patterned vector optical fields
Author(s):Cai, Mengqiang(1); Tu, Chenghou(1,3); Zhang, Huihui(1); Qian, Shengxia(1); Lou, Kai(1); Li, Yongnan(1); Wang, Hui-Tian(1,2)Source: Optics Express Volume: 21 Issue: 25 DOI: 10.1364/OE.21.031469 Published: December 16, 2013Abstract:We numerically and experimentally explored generation and regulation of subwavelength multiple focal spots produced by tight focusing patterned vector optical fields (PVOFs). We presented a modified Richard-Wolf diffraction integration method suitable for the tight focusing of the PVOFs. By tailoring the spatial geometry and the polarization distributions of the PVOFs, simulations show that the diverse spatial configurations of subwavelength multiple focal spots can be achieved. To verify our idea, we experimentally generated the theoretically calculated examples of femtosecond PVOFs, then tightly focused them on the surface of the crystalline silicon wafers, and finally characterized the morphologies of modified surfaces. The SEM (scanning electronic microscopy) images confirmed that the experimental results are in good agreement with the simulations. Based on the diverse controlling degrees of freedom of PVOFs, the resultant subwavelength focal fields are flexible and powerful in parallel processing, optical manipulation and so on. ? 2013 Optical Society of America.Accession Number: 20135217127635