最新刊期
期 6 ， 2014
- 摘要：In recent years, the response speed of LCDs has been greatly improved. The response time has been reduced from 25 ms to 3 ms or less. Although this improvement related to reducing thickness of the liquid crystal layer, the main reason was attributed to the studying and using of novel liquid crystal mixtures. Sequential color LCDs can produce higher quality images, but prerequisite is to have fast response liquid crystal materials. The three main factors which influence the response time of the LCDs are the rotational viscosity coefficient of the liquid crystal, the birefringence and thickness of the liquid crystal layer. This paper focuses on the birefringence of liquid crystal and describes several factors which influence the birefringence from the molecular structure of the liquid crystal compounds, including the central ring structure, the bridging groups on the center, the polar group and the "-F" on the lateral. Extending the length of π-electron conjugation of molecules can improve the birefringence of liquid crystal. This paper lists the molecular structures and birefringence of several nematic liquid crystal compounds with high birefringence which has been synthesized. Finally, the research of high birefringence liquid crystal is prospected.关键词：fast response;high birefringence liquid crystal;molecular structure;length of π-electron conjugation
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发布时间：2020-08-12 - 摘要：In the Thin Film Transistor Liquid Crystal Display(TFT-LCD) industry,there are two orientation film coating method.One traditional method is roller coating, the other one is inkjet printing.This paper introduces the new film coating method inkjet printing and the traditional method roller coating,especially introduces the new printing method.This paper introduces three defects caused by new printing method, such as line Mura, head Mura,and cloudy Mura. The intrinsic reason of these Mura is researched by analyzing many tests data and studying the theories, it also raises some improving measures and suggestions. By strengthening the scientific management of equipment and combining with the theory research,the ratio of these Mura drops obviously.What we have done also establish the basis for further analysis.关键词：polyimide;alignment film;inkjet printing;Mura
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发布时间：2020-08-12 - 摘要：A novel type of tandem organic light emitting device(OLED) was demonstrated by employing LiF/Al/F4-TCNQ/NPB as charge generation layer(CGL). By contrast experiment, it is suggested that the optimum thickness of F4-TCNQ and Al in CGL is 8 nm and 5 nm, respectively, which exhibits the good ability of generating charges and higher optical transmittance.Based on the optimized structure of CGL, we fabricated the tandem OLED with the emission layer of CBP:6%Ir(ppy)3. By comparing the device performance of the tandem OLED and conventional single OLED, it was found that the highest current efficiency and power efficiency were 51.6 cd/A and 28.4 lm/W, which was 2.16 times and 1.8 times as high as that of single OLED, respectively.In conclusion, the tandem OLED with the CGL of LiF/Al/F4-TCNQ/NPB can improve the power efficiency of OLED. In addition, replacing conventional inorganic metal oxide with organic material of F4-TCNQ in CGL can avoid the destruction of film formation of Al layer, inducing in improving in performance and weakening the efficiency roll-off phenomenon.关键词：charge generation layer;tandem;OLEDs
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发布时间：2020-08-12 - 摘要：Phosphor transformation is the main method of producing white-light LEDs. However, most phosphors in the market are lack of red component or color stability,because most commercial LEDs produce cool white light. Thus it is realistic to search for new red phosphors with high stability and low cost. In this regard, borates, chemical stable and easily productive, have attracted our attention.The structure and photoluminescence properties of KZn4(BO3)3 doped with Eu3+ are analyzed.We have synthesized a series of KZn4(BO3)3:Eu3+ with different doping concentration by solid state reactions. From the X-ray diffraction data, it is concluded that Eu3+ ions are inclined to occupy Zn2+ site in the structure of KZn4(BO3)3. And the PLE indicates that the best exciting wavelength(393 nm) of KZn4(BO3)3:Eu3+ is near ultraviolet, which makes it suitable for near-UV LEDs. According to the PL, the strongest peak locates at 590 nm which is ascribed to the transition of 5D0-7F1.In addition, the quenching concentration of Eu3+ is about 1.5%, and the critical distance is about 3 nm.Finally, the CIE coordinates of KZn4(BO3)3:Eu3+ is(0.629 7,0.369 9), which has high color saturation.The material is a potential red phosphor used for LEDs.关键词：material;light-emitting diode;phosphor;rare-earth ions;photoluminescence property
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发布时间：2020-08-12 - 摘要：In order to improve the transparency of the transparent liquid crystal display and reduce the power of back light source,the relationship between chroma and transmittance of color filter in the transparent liquid crystal display is investigated. First, based on the appropriate spectrum of RGB color resistance, 10% NTSC and 45% NTSC color film samples are produced, and the white light transmittance is tested, then transparent display cabinets are produced. Comparison of transparency transparent display cabinets with different NTSC color filters is made. Experimental results indicate that the chromaticity of color in color filter is reduced selectively to improve the transmittance of color filter, and then high transparent liquid crystal display is achieved.With this solution, we produce color transparent display samples which have chromaticity field of 45% and 10% NTSC, and white light transmittance reach 10% and 15% respectively.The transparent liquid crystal display cabinets have better transparency.关键词：transparent liquid;crystal display;color filter
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发布时间：2020-08-12 - 摘要：In order to determine the fault reason of TDI CCD camera imaging system during temperature cycle experimentation, the failure tree is established through fault mode effect and harm analysis. Through detail checking and testing, the fault is located in the region where the surface mount resistor is mounted for address. The failure analysis of this chip resistor is done in the components reliability center through electric test and DPA. Checking results show that exceptional stress causes terminal break off of the resistor during operation. The lot default probability is also precluded. The exceptional stress is derived from long time soldering during the repair by the soldering people. This thermal stress causes the terminal break off of the resistor. The fault is located correctly. The improved measure is limiting the soldering time of chip resistors strictly no more than 2 s. The principle is also clear. The solution is effective after experimental validation.关键词：failure analysis;failure of resistor;failure tree;terminal break off of resistor
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发布时间：2020-08-12 - 摘要：Dye-doped chiral-nematic liquid crystal laser was designed and manufactured, and the laser radiation was researched. The chiral-nematic liquid crystal laser device of planar texture was prepared by doping laser dye PM597 and chiral compound S-811 into nematic liquid crystal TEB30A. By using a second harmonic Q-switched Nd:YAG pulsed laser(λ=532 nm) as pumping source, the laser of 571.1, 615.5 nm are obtained at the short-wave and long-wave of the photonic band edges.The theory of density of optical state is used to prepare dye-doped cholesteric liquid crystal laser. According to the proper proportion of device component, the curve of density of state varying with the wavelength is simulated. In the device, density of optical state is maximum at the wave of the photonic band edge, threshold is lower and laser radiation is obtained easily.关键词：chiral-nematic liquid crystal;dye-doped liquid crystal laser;density of optical state;photonic band edge
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发布时间：2020-08-12 - 摘要：In order to meet the requirements of LED matrix controller in the different occasions and accomplish adjust different parameters properly,this paper introduces an implement of LED Matrix system controller based on FPGA through finite state machine. The primary control logic of the controller is integrated into FPGA device, which is composed of Serial Communication Module, Dual-port RAM Modules, LED Matrix Modules and Clock Generator Modules. Dual-port RAM Modules is customized by LPM. The other modules are described by Verilog HDL. The controller and the drive board are connected by the 08 port. The controller and PC monitoring center can communicate with each other through RS-232 serial bus. The simulation results on the Quartus Ⅱ platform and operation performance showed that the controller possess the characteristics of hardware simplicity, expansion easy and high reliability.关键词：LED matrix controller;FPGA device;FSM;simulation
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发布时间：2020-08-12 - 摘要：In order to share screen among intelligent devices with high quality and low band width, a screen sharing system based on embedded system has been designed and implemented, which consists of a cross-platform client and server. For the purpose of reducing bandwidth and improving screen quality, a self-adaptive method based on scene recognition is proposed, which could recognize the application scene intelligently and adjust H.264 code rate according to network congestion state and application context. On the other hand, the server has been deployed on embedded board. For the server side, a solution based on multiple threads has been proposed, which consists of main thread, message receiving thread, decode thread and display thread. Every thread focuses on their own task, which could improve the robustness and coupling dramatically. Experiment results show that the proposed screen sharing system could support screen sharing between PC and embedded display system with 720 p high resolution. And this solution has the advantages including real time, low-bandwidth and low cost.关键词：screen sharing;embedded system;Linux;H.264
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发布时间：2020-08-12 - 摘要：To meet the demand for waveform-generator in the laser control system devices, a platform for designing the visualization versatile waveform generator is built based on the S3C2440 processor and the Altera's FPGA chip, and the DDS synthesis algorithm used in this platform is simulated. The hardware is built by using the S3C2440 processor and driving a TFT LCD screen and a four-wire resistive touching screen directly. VHDL language is used for the processor data interface and the appropriate DDS is selected on the basis of the IP. According to the input options and parameters, the desired waveform signal is output by a frequency and a phase generated by the DDS and amplitude generated by the DAC0832, respectively. Test results show that the platform can be used to generate and display the waveform curve completely by inputting the parameters in the touching screen. Compared with the conventional function generator, it has the merits of good applicability, easy use and low cost. The waveform-generator can be used and meet the test requirements in the laser control system.关键词：S3C2440;DDS;waveform
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发布时间：2020-08-12 - 摘要：In order to adapt the development trend of low-power and high-integration in cockpit display system, a method about graphics generation circuit based on Zynq is proposed in this paper. Hardware platform is designed based on Zynq and the graphics generation algorithms are performed by ARM processor integrated in Zynq. A triple buffer mechanism is designed to manage the data of DDR3 SDRAM frame buffer and the graphics can be generated in real-time in cooperation with FPGA. Graphics with different resolution can be generated using the proposed design. Experiments show that the EFIS display with 1 024×768 resolution can be generated and the frame rate is 74 fps, which satisfies the high performance requirements of the cockpit display system.关键词：Zynq extensible processing platform;graphics generation;DDR3 SDRAM frame buffer;triple buffer mechanism
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发布时间：2020-08-12 - 摘要：In order to create an efficient, intuitionistic and multi-mission embedded development platform, the embedded experimental environment was designed based on the μC/OS_Ⅱ, μC/GUI,STM32 MCU and ILI9320 LCD. Research was done to explore the migration method of the μC/OS_Ⅱ and μC/GUI and to optimize the μC/GUI on the lack of the Chinese and low rate of the screen refresh.The organizational structure of the μC/OS_Ⅱ and μC/GUI were studied, and the files that were closely associated with stm32 mcu were rewritten. At the same time, the operation of the μC/GUI transplantation was done based on the success of the transplantation of the μC/OS_Ⅱ including the modification of the files related to the μC/OS_Ⅱ and the adaptation of the μC/GUI bottom-driven functions. And Chinese font library was added to the system based on the successful transplantation of the μC/GUI.The μC/GUI functions of drawing pixel,line and rectangle were rewritten to increase the screen refresh rate. The experimental results show that the four created tasks run regular services, and the Chinese character displayed normally. The screen refresh rate increased from 996 080 to 1 629 060 pixel/s. The μC/OS_Ⅱ and μC/GUI worked cooperatively and the optimization of the μC/GUI functions improved the screen's performance.关键词：μC/OS_Ⅱ;C/GUI;integration;optimization
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发布时间：2020-08-12 - 摘要：Aiming at the problem of performance testing about high-precision and high-speed optical shaft encoder in the field of aerospace,the function of display in rapid detection system based on aerospace photoelectric encoder was designed. The system could simultaneously complete acquisition, processing, communication and display of multiple optical encoders. DSP + CPLD was core processing module. CPLD controlled the high-speed A/D to complete photoelectric encoder signal acquisition and data latches coarse code. DSP was responsible for the completion of processing crude code and precise code encoder signal, data communication and display. The data information of processed was transmitted by the dual port RAM in the customize communication interfaces. Each of the encoder reading from RAM about the angular position in binary and degrees, minutes, seconds form were displayed in the LCD screen by external buttons controlling. The results show that the system can handle data signal of multiple encoders, data transmission and display. The system is good real-time and strong visibility. Display function of system can be further expanded.关键词：photoelectric encoder;detection system;display;dual port RAM;LCD
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发布时间：2020-08-12 - 摘要：Aiming at a real-time display of operation data in the PV control and inverter integrated vehicle, based on STC12C5A60S2 and JLX12864, a human-machine interface module has been introduced. Along with the introduction of the hardware circuit of this liquid-crystal display module, the software programming part is also analyzed. A human body infrared sensor module is added to control the backlight of LCD. Furthermore, the principle of communication between this module and the PV control and inverter integrated vehicle to realize the real-time display is also mentioned. In case of power outage, operation data is designed to store in EEPROM of the STC12C5A60S2. This module has been successfully applied in the PV control and inverter integrated vehicle. Stability and ability of real-time display has been indicated by experiments. This module indeed has some practical and refe-rence value.关键词：STC12C5A60S2;JLX12864;liquid-crystal display;infrared sensor;communication
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发布时间：2020-08-12 - 摘要：For the current domestic market, most of multiple asynchronous LED display management system based on LAN or 485 bus technology have many problems such as screen limited distribution geographical scope, costly cabling, localized user operations,single project managed and so on.To solve these problems, an open multiple-project multiple-users multiple-screen cluster management system based on Internet technology is designed and implemented in this paper.In the system, a data relay server and a media are designed as a bridge of communication between user and asynchronous LED display on Internet, a relational database is built to maintain the information of client companies, users, LED screens and associated relationships between them on data relay server, and a set of scalable layered communication protocol is designed.This system provides a highly optimized implementation method for data relay server. Otherwise, a reusable architecture of client software and asynchronous terminal software are designed. After testing, system can operate stably and efficiently, achieve the ability that multiple-user can control the remote multiple-asynchronous LED display in real-time at any location that can access the Internet.关键词：asynchronous LED display;cluster management;data relay sever;boost library
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发布时间：2020-08-12 - 摘要：In order to reduce the complexity and cost of optical observation system for air, a general purpose emulation system is designed and produced based on liquid crystal(LC) screen with VGA port to simulate the space objects in lab. In addition, this paper investigated the algorithm of real-time updated object's shape and energy based on its space position and atmospheric density used in the system.The system is composed of S3C2440 processor and VGA port. At every moment, it calculated the object's parameters including height, distance and velocity. With these parameters, it calculates the object's position and size on screen in real time according to atmospheric density variation and energy limitation. Finally, the emulated object is displayed on the LC screen through VGA port. The experimental results indicate that the experimental cost with our system is decreased by 90% than those in field. In addition, the system has the advantages of randomly change and good repeatability. It can emulate different space objects in a single background.关键词：VGA;air targets;simulator
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发布时间：2020-08-12 - 摘要：An equivalent circuit model for the 2T1C driver in delay array is established starting from transmission voltage and circuit equations. Gate signal voltage function is also provided after comprehensively considering various parameters in gate signal transmission circuit. The dependent relation of gate signal delay on LED display size, display resolution and gate electrode material is simulated through numerical computation. The difficult problem of gate signal solution under complex parameter environment is addressed and theoretic calculation basis is contributed for satisfying the requirements of LED display size, display resolution and material parameter.关键词：gate electrode;signal delay;equation
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发布时间：2020-08-12 - 摘要：Two analytical models are proposed to analyze the energy recovery efficiency of PDP data driver IC. DPLD(double-channel p-type lateral extended drain MOS) transistor is the key device of energy recovery circuit of data driver IC. CRC(Capacitor Resistor and Capacitor) equivalent circuit model is suitable for DPLD transistor which has poor drain current capacity. VCCS(Voltage Controlled Current Source) model is suitable for DPLD transistor which has strong drain current capacity. The test results reveal that both CRC and VCCS models have high precision, the model errors are 2.26% and 4.04%. CRC model reveals that the energy recovery efficiency of data driver IC is influenced by three factors,which are the charge time, channel resistor and load capacitor. The compared results of two models show that channel resistor has great influence on energy recovery efficiency of data driver IC. The energy recovery efficiency of PDP data driver IC can be improved significantly by using DPLD transistor which has smaller channel resistor. The proposed CRC and VCCS models can be used to predict the energy recovery efficiency accurately.关键词：analytical model;PDP data driver IC;DPLD transistor;address power;energy recovery efficiency
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发布时间：2020-08-12 - 摘要：In order to overcome the influence of illumination changes on detecting results by using codebook-based object detection algorithm, an improved codebook algorithm that fuses Kalman filtering is proposed in this paper. The algorithm calculates the pixel brightness change in YUV colour space, which corresponds brightness changes with spatial coordinates and makes the calculation of brightness process fallen by an average of 44.9%. Meanwhile, it initializes a Kalman filter for each pixel at the time when the codebook model is established and the filter uses two successive image's brightness information to predict and correct current pixel value. This method has good adaptability on brightness changes. The experimental results show that this algorithm reflects a better adaptability under the condition of brightness changes, compared with ordinary YVU codebook model, RGB codebook model and GMM method.关键词：object detecting;codebook model;Kalman filtering
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发布时间：2020-08-12 - 摘要：The location accuracy of circle target center in vision measurement system is susceptible to the noise. In order to enhance the capacity of anti-interference of noise and improve the location accuracy, a modified subpixel location algorithm of circle target center based on geometric features is proposed in this paper. Firstly, coarse location of circle target center is realized by combining adaptive threshold segmentation and centroid method, which is used for radius constraint of the edge detected by Canny operator to remove the isolated points and the noisy points. Then, starting from the geometric distribution characteristics and linking discipline of the ideal imaging of circle,a method based on partition theory is brought forward to obtain ideal and continuous edge of circle target. Finally, Zernike moment is used to carry out the subpixel location of the edge, and the center location is achieved by the least-squares ellipse fitting method. The experiments results show that the location accuracy can reach to 0.023 7 pixels,and the operation time is between 2 and 3 ms. It can satisfy the high requirements of precision, stabilization and real-time ability of circle target center in the measurement system.关键词：vision measurement;edge detection;geometric features;Zernike moment;ellipse fitting
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发布时间：2020-08-12 - 摘要：Compared with conventional display technology, holographic projection technology has outstanding advantages. The phase retrieval algorithm is a key image processing algorithms in holographic projection technology. The constringency speed and precision of these algorithms need to be raised. The performance of the algorithms above are not satisfactory, sometimes they cannot even guarantee that the iterative process converges to the correct solutions. Then, this paper proposes a parallel architecture based on the phase recovery algorithm-Parallel Gerchberg-Saxton with Genetic Algorithm(PGSGA). Simulation has proved that the proposed algorithm PGSGA is better in convergence rate and the restoration quality by testing gray-scale image.关键词：holography;ViHPS;phase retrieval algorithm;phase-only hologram;GS algorithm
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发布时间：2020-08-12 - 摘要：As the biological vision features show superior performance to images representation, a non-reference image quality assessment approach based on biological vision features is proposed. The standard model of biological vision is studied and analyzed, and the sparse representation of image is accomplished through the model.The mapping correlation between biological vision features and image quality scores is trained with the regression technique of least square-support vector machine, which gains the regressor that can predict the image quality.The score of image quality assessment is accomplished with the trained regressor at last. The experimental results based on LIVE database show that the proposed approach has predicting error of 2% and 5% for specific distortion and cross-validation distortion respectively,and exhibits a superior accuracy and monotonicity compared to state-of-the-art quality assessment approaches.关键词：non-reference image quality assessment;biological vision model;standard model features;least square-support vector machine;distorted images
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发布时间：2020-08-12 - 摘要：LCD screen requires strict surface cleanliness. The inspection method based on digital image processing focusing on the residual liquid crystal can give quantitative and objective assessment on the components surface cleanliness. According to the difficulty to identify the rudimental liquid accurately in a complex background image, this paper proposes an effective image processing flow and algorithm,including the operation of segmentation, edge connection, image filling, redundant boundary and noise removing, etc. An edge connecting operator is designed to connect the discontinuous boundary in the image after the segmentation. A classifier is designed and implemented based on binary classification method for automatic identification of geometry types of contaminants. Experiments show that the residual liquid crystal in the simple background image can accurately inspected, and the interference of the noise is excluded. The identification and analysis method for the complex background image can accurately process particular types of images that their backgrounds have significant differences.关键词：image processing;recognition of contamination;pattern recognition;liquid crystal screen
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发布时间：2020-08-12 - 摘要：Fast fusion of multiple low dynamic range(LDR) images is essential for the real-time performance of a high dynamic range(HDR) video acquisition system using multi-exposure method. This paper proposed an improved fusion algorithm based on multi-resolution pyramid decompose. The algorithm dramatically reduces computing complexity while preserving the fusion quality of the original method. The proposed method improves the real-time performance in the following aspects: pyramid decompose convolution core, Gaussian coefficients expansion method, Laplacian coefficients fusion rule, Gaussian coefficients fusion rule. The computing complexity of pyramid decomposes, fusion, and reconstruction is reduced. Experiment results shows that the proposed method is stable and got good fusion results. The method is applied to a launch vehicle observation system. The computing speed is boosted 10 times and it takes 8.9 ms to fuse one 512×512 frame on TM320MD642 DSP, fulfilling the real-time requirement of 25 fps HDR video acquisition system.关键词：high dynamic range video;HDR;multi-exposure;image fusion;pyramid decompose
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发布时间：2020-08-12 - 摘要：Environmental illumination and mobile phone screen brightness is the two major factors which influence the effects of mobile phone display performance. This paper tests the function of brightness automatic adjustment of three different mobile phones under 14 environmental illumination levels and designs a subjective experiment of image quality assessment under 24 different environmental illumination and mobile phone luminance combination. And the paper measures the display quality parameters under 12 different environmental illumination and mobile phone luminance combination on the basis of subjective experiment.The subjective experiment results show that the rise of mobile phone brightness can improve the display effect of mobile phone, and the optimal mobile phone brightness is changing under different environmental illumination values. The test experiment results show that the rise of mobile phone brightness can improve the luminance contrast, color saturation and color gamut range of mobile phone.关键词：vision;color and vision optics;environmental illumination;mobile phone brightness;display quality;polynomial fitting
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发布时间：2020-08-12 - 摘要：To solve the image color reproduction problems for display devices, a gamut mapping algorithm based on image quality assessment and image segmentation-fusion strategy was proposed.Firstly, different sorts of gamut mapping algorithms were analyzed in detail and 4 algorithms were chosen as basic algorithms. And then, a gamut mapping image quality assessment method was proposed, and SLIC superpixel algorithm was used to carry out the source image segmentation. Gamut mapping was applied to the source image with the basic algorithms, and similarity was calculated within each image segment between mapped images and source image. According to the calculated similarities, each mapped image was chosen and comprehensively processed, and fused to the final image. Finally, with LED display panel and LCD display as an example, a subjective evaluation experiment was made to the proposed algorithm and other basic gamut mapping algorithms. Experiment result shows that the proposed algorithm is apparently better than other ones on keeping image color fidelity, and yet the calculation speed still needs to be improved.关键词：image quality assessment;display panel;gamut mapping;LED display
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发布时间：2020-08-12 - 摘要：According to the radiometric calibration experiments in laboratory, the reflector-based mosaic CCD camera's image non-uniformity caused by vignetting phenomenon was corrected. Firstly, the image un-uniformity reasons of reflector-based mosaic CCD camera are analyzed, and the irradiance deviation received by different CCD pixels in focal plane is the essential reason for images' non-uniformity. Then, the CCD pixels' irradiance responsivity calibration experiment and the whole camera's non-uniformity calibration experiment were carried out in the laboratory, and the relationship between each pixel's receiving irradiance and camera's incident radiance was built. Lastly, a correction algorithm is put forward based on the above relationship to calculate CCD pixels' correction factors, and the correction factors were used to correct the vignetting image. The correct experiment indicates that, within a certain range of incident radiance, the non-uniformity of original calibration images are above 16%, and after correction, the values decreased to 1% or less. Besides, the correction factors were used to correct the images of outdoor experiments and it works very well.关键词：reflector-based mosaic camera;radiometric calibration;non-uniformity correction;vignetting
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发布时间：2020-08-12 - 摘要：Aiming at the shortcoming that Camera Link has complex interface and can only transfer in short distance, an interface converting system converting Camer Link to HD-SDI is designed. A high performance FPGA EP2S60F1020 of Altera Company is used to acquire the image data and code the data based on SMPTE 274M standard. To solve the problem that the horizontal and vertical time are different between Camera Link and HD-SDI, 3 pieces of SDRAM are used as frame buffer. And the output frame of HD-SDI is delayed for a frame. The coded data is output to a serializer LMH0030, and the HD-SDI data is the output. As the vertical time of Camera Link and HD-SDI is not accurate the same, a frame must be dropped after every 708 frames. But the images being processed by the FPGA are not dropped. The result shows that the system can convert images coming from Camera Link to HD-SDI. And the data output can be acquired by a SDI acquiring card.关键词：camera link;convert;FPGA;SMPTE 274M;HD-SDI
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发布时间：2020-08-12 - 摘要：Five key indicators, including crosstalk ratio, luminance, contrast, color temperature, color gamut, were measured in the three mainstream glasses 3D displays. First, a series of measuring programs were designed according to imaging principle of glasses 3D displays. Measurement results show that the crosstalk ratio of color type 3D display is highest which the left eye is 9% while the other one is 3%. On the other hand, the crosstalk ratio of polarization type 3D display is 1.79% in the horizontal direction while it appears an oscillation distribution in the vertical direction. Besides, division type 3D display has a lowest crosstalk ratio with 0.37%. A luminance decline occurred in glasses 3D displays, especially for the division type 3D display: luminance remains only 6.97 cd/m2 in 3D play mode with a substantial decline in contrast. In color gamut area, compared with 2D play mode, division type 3D display still has a color gamut of 72.7% in a standard of NTSC after a significant decrease. And the smallest color gamut existed in color type 3D display with 0.3%. These results can be used to improve the properties of glasses 3D displays.关键词：display evaluation;glasses 3D display;crosstalk;3D measurement
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发布时间：2020-08-12 - 摘要：The field-dependent hole mobility of Tips-PEN film prepared by solution-process was extracted with steady-state SCLC and impedance spectroscopy method,and the results of the two methods were compared and analyzed. The samples used in this study have a general structure of p+ Si/PEDOT:PSS / Tips-PEN /Ag, which is a single-carrier device. For Tips-PEN thickness of 87 nm devices, the zero field mobility and the field-dependent factors obtained with steady-state SCLC were 1.21 × 10-5 cm2/(V·s) and 0.002 4(cm/V)1/2, respectively. For thickness of 827 nm device,the zero field mobility and field-dependent factors obtained with impedance spectroscopy were 1.219 × 10-5 cm2/(V·s) and 0.003 47(cm/V)1/2,respectively. The smaller field-dependent factor obtained by steady-state SCLC shows that the mobility is weaker dependent on the field. This is due to much higher electric field applied in order to get steady-state free-trap SCLC than that in impedance spectroscopy and then higher carrier concentration is injected. The result shows that there is weaker electric field dependence of mobility in higher carrier concentration and is consistent with theoretical model and simulation.关键词：Tips-Pentacene;space charge limited current;impedance spectroscopy;mobility
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发布时间：2020-08-12 - 摘要：To solve the problem of low power-saving and high overflow distortion rate of exist dimming algorithms, this paper proposes a dynamic dimming algorithm of high power-saving and low overflow rate.Considering that the backlight and pixels luminance have different influence on display effect in LCDs, input images are preprocessed to calculate the image luminance.The compensated pixel luminance is calculated by a weighted linear adjustment method.The simulation results of the proposed algorithm indicate that the average power-saving could reach 22.15% with overflow distortion of 9.95%, while the common algorithm only has 11.9% and 12.34%, respectively.The actual test is implemented on the prototype.Compared to common dimming algorithms, it can present good display quality without sensitive luminance decrease as well as higher power-saving rate.关键词：dimming technology;backlight;power-saving;overflow rate
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发布时间：2020-08-12 - 摘要：To solve the contradiction between energy consumption and display quality in the LCD display effectively, on the basis of a comprehensive analysis of the relationship between image backlight and features such as gray histogram or dominant gray level, this paper proposes the dimming algorithm with these characteristics. First of all, a classification into three classes based on the average gray is performed for the input image. Then image characteristic values are computed such as gray histogram and dominant gray level. Finally the backlight dimming brightness is calculated according to formula, whose coefficients are determined by the multiple regression analysis to analyze the relationship between image features and backlight. For 30 typical images, the simulation result show that the dimming effect index is 0.95, the average energy saving rate is 28.22%. Compared with other dimming algorithms, this algorithm has higher power-saving rate and better display effect, moreover,it trades off the contradiction of the display effect and energy saving rate.关键词：dimming;backlight;dominant gray level;multiple regression analysis;DEI
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发布时间：2020-08-12 - 摘要：Liquid crystal displays have two shortcomings of low CR and power efficiency. Dynamic dimming can help LCD to achieve high contrast ratio and reduce power consumption. The evaluation method balancing display effects after dimming and power-saving ratio can efficiently reduce the deve-lopment risk. Until now there is no agreed evaluation method. Combining three parameters of peak signal-to-noise ratio, structural similarity index measurement, and mutual information, the display effect index is proposed to evaluate the display effect after dimming. The dimming effect index is then introduced to balance the power-saving and display effect. The images belonging to six classifications of different luminance and contrast ratio are used to make the evaluation on several mainstream dimming algorithms. Based on the dimming effect index, the most suitable applications of the dimming algorithms are analyzed.关键词：dynamic dimming;algorithm evaluation;power reduction
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发布时间：2020-08-12 - 摘要：In order to reduce optical distance(OD) and realize ultra-thin design of direct-lit LED backlight module, this paper proposes a kind of diffuser plate with prism-based micro-structure on the bottom. The optical theoretical analysis is first performed on the prism-based micro-structure, which proves to be feasible to reduce the OD. The prism-based micro-structure is then practically tested and utilized in 81.3 cm(32 in) LED backlight. Experimental results show that the diffuser plate with prism micro-structure has effect on increasing the diameter of LED shadow by about 10% and reducing OD. The OD of the prototype with 32 in LED BLU is reduced from 13 mm to 11.8 mm.Such diffuser plate with prism-based micro-structure can help to realize the ultra-thin design.关键词：direct-lit LED backlight unit;annular prism micro-structure;ultra-thin design
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发布时间：2020-08-12 - 摘要：Through theoretical analysis, RGB three primaries LED backlighting with appropriate line is chosen in a LCD backlight with narrow gamut, which can raise the color gamut from 40% to 70%. And the test fitted well with analysis, but the mixing ratio of three primaries direct-lit backlight is 1.3:1, larger than 1:1 of full white backlight. The white LEDs were doped into three primaries LED backlight, which can reduce the mixing ratio. As the brightness of the white light increases, color gamut will be reduced. When color gamut changes from 70.2% to 63.7%, the white luminance is 30% of the total luminance, and the mixing ratio is descended to 1.1:1.
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发布时间：2020-08-12 - 摘要：Image tracking is focused by many researchers, and it has been one of the key technologies of the image processing. With the continuous development of microelectronics technology, it requires more and more for video tracking system in practice, such as theodolite and optical platform of UAV. The current video frame rate of the image tracking system is too low, it has formed large constraints on transmission bandwidth of the servo system. While, there are bottlenecks on transmission using high frame rate. In order to solve the above problems, this paper designed a image tracking system based on TMS320+FPGA+SDRAM. In this system, the data of image output are send out after SDRAM controlled by FPGA cached, so that the video frame rate becomes low, and it can be real-time tracked and displayed. In order to meet the requirements of real-time tracking for 100 frame/s video, this paper make the correlation algorithm further simplified. Experimental results show that this system can work effectively and stably, and it can meet the actual needs of the project.关键词：target tracking;TMS320C6455;SDRAM;image processing
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发布时间：2020-08-12 - 摘要：Real-time UAV video data compression is one of the key technology of UAV. In this paper we propose a real-time, low-power video encoding system design, based on DM368 processor and embedded Linux operating system. Compared with traditional embedded video H264 encoding system design, we use DM368 inner video image co-processors to process the encoding task, which has the advantage of low-power consumption, low processing delay, and simple external circuit design. Furthermore, we utilize the real-time, stable and efficient embedded Linux operating system, capable of processing multi-task, such as video capturing, hard-core scheduling, serial communication, and data transmission. Experiment shows that the average power consumption of our system is only 1.5 W when dealing with the PAL video H264 coding task. Our design meet the requirement of UAV video compression task efficiently, with the advantage of low-power, low-cost, small-size, light-weight, and good real-time quality.关键词：UAV;DM368;video compression;H264 encoding
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发布时间：2020-08-12 - 摘要：In order to realize the accurate measurement of irradiated spot in moving target in laser guidance, a relatively measuring system with high precision is established. The spot detection, precise timing control and moving target tracking problems are deeply studied. First, the principle and realization of spot detection are introduced, which ensure the spot is detected quickly and accurately in different light conditions. Then the precise timing control technique is used to realize the collection of synchronous sampling spot signal and image, which completes monitoring of the laser coding mode. Finally, target panel is tracked by the visible sensor, and light spot image is collected by infrared sensors. In order to detect target plate edge in the grassland complex background and low contrast condition, directed edge operator and line segment detection algorithms are used. The trajectory prediction algorithm is used to ensure the stable target tracking and accurate detection of laser irradiation. Through the field experiments, the system is proved the ability of automatical measurement of the spot timing characteristics and spatial characteristics. Timing accuracy is 0.07 μs and the position accuracy is 0.04 mrad. The method can meet the requirement of stable tracking and accurate measurement of target irradiation.关键词：laser spot;laser coding;accurate timing;moving target
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发布时间：2020-08-12 - 摘要：A radar warning situation map(RWSM) is proposed in this article. This map can measure the distance, bearing, heading, velocity of the object and show these information on the monitor through the panorama and the radar map. The system obtained the video and the orientation of the object by the visible light detector. It calculated the image and the motion of the tracking target through the image processing algorithm and the pattern recognition method. The panorama technology was combined to form the RWSM. The laser range finder was replaced by the digital image processing and recognition technology to estimate the distance of the target very well. The ship experiment results showed that the RWSM can well present the posture of the targets, and the system can track the objects accurately and steadily. The cost of the system has been deduced greatly by the method.关键词：photoelectric tracking system;target tracking;detection;range finding;image recognition
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发布时间：2020-08-12 - 摘要：A CMOS camera measurement system which recognizes and measures the cooperative target in some space project is presented. EV76C560AR made by E2V is used as image sensor in the camera measurement system. The V4 series FPGA and C67x series DSP are the core of the image processing. The processing procedure of data streams including image compressing, data exchange and message communication is described. The paper uses FPGA to realize H.264 video code standard, the control of the RT terminal of 1553B bus, and the image data exchange among FPGA, DSP and SRAM by finite-state machine. This camera measurement system has been used in the space measure project.关键词：FPGA;H.264;state machine;1553 bus
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发布时间：2020-08-12 - 摘要：Stereoscopic display can provide depth information and immersive knowledge about the scenario for the observers. In order to build the low-cost prototype of stereoscopic display system which can aid remote operation, a real-time stereoscopic display system without the calibration to the camera was designed. The system utilized binocular web cameras and stereo display device to provide two stereoscopic display modes: anaglyphic mode and active shutter mode, the performance of which are evaluated by MOS method. Experimental results show that the two images of the binocular web cameras are row-aligned rectified. In the case of parallel processing of images with multi-thread technique, the frame rate of the stereo image output is upgraded to 30 Hz from 21 Hz, which meets the real time requirements. Evaluation proves that the score of anaglyphic mode and active shutter mode are 7.67 and 9.08, respectively. The performance of stereoscopic display is basically satisfactory.关键词：stereoscopic display;uncalibrated;stereo rectification;web camera;binocular
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发布时间：2020-08-12 - 摘要：The paper studied the principles of image matching algorithms and analyzed the different matching algorithms. By the principle of grayscale features encoding, the improved matching algorithm is presented and is realized by FPGA. The improved mid-value filter and matching algorithm based on grayscale features encoding is realized in the experiments. The matching effect is tested for visual image and infrared image under different background conditions. The experiment results show that the matching algorithm is easy for FPGA design and can enhance the real time performance.关键词：target tracking;DSP;complicated background
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发布时间：2020-08-12
Table of contents
- 摘要：A conductive film with new structure for surface conduction electron emitter is proposed in this paper. Since the specific conductive film structure is narrower in the middle part, the joule heat in this region can be larger than that in the other region. This may lead to a thermal stress concentration in the middle region, and finally cause the nano-scale fissure to be generated easily from this position. With this new conductive film structure, the formation position of the nano-scale fissure can be controlled easily. The results indicate that the nano-scale gap position formed in the conductive film can be controlled to some extent. SCEs with the specific conductive film have better uniformity compared with the SCEs with the conventional conductive film structure. For an anode voltage of 2.0 kV and a device voltage of 14 V, the emission current of the SCEs with the specific conductive film can reach 18 μA.关键词：SED;new conductive film structure;electro-forming process
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发布时间：2020-08-12 - 摘要：In order to improve the chromatic aberration in color LCD device and enhance the display quality, the effect of RGB transmittance on chromatic aberration was simulated for a particular pattern of(128,192,192) gray scale. By respectively adjusting the thickness of RGB film, not only the relative cell gap of RGB was tuned, but also the transmittance of RGB was adjusted to improve RGB gamma curves, and chromatic aberration was compensated and optimized. Experimental results show that the increase of G and the decrease of B in cell gap, can obviously improve chromatic aberration. Meanwhile, when the thickness of RGB keeps no change, chromatic aberration is proportional to cell gap of liquid crystal. Cell gap reduces by 1%, chromatic aberration correspondently decreases about 0.2. When the cell gap of RGB changed from(3.47,3.38,3.4) μm to(3.5,3.45,3.36) μm and(3.5,3.44,3.28) μm, the average chromatic aberration of sample was reduced from 13.8 to 12.8 and 12 in the pattern, respectively. Thus, chromatic aberration can be compensated by separately adjusting the relative thickness and cell gap of RGB.关键词：chromatic aberration;liquid crystal display;cell gap;gray scale
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发布时间：2020-08-12
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