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摘要：With 3-amino-2-methylbenzoic acid as starting material,five asymmetric bent-core liquid crystals containing Schiff-base unit were synthesized. Their chemical structures were confirmed by ¹H NMR and HRMS spectra, their liquid crystalline properties and phase transition temperatures were studied by DSC and polarizing microscopy with heating stage.It was found that the clearing points of the synthesized molecules were decreased with the decreasing of the number of benzene rings of the compounds, companying with the decreasing of the liquid crystal stability.The molecules with 5 benzene rings exhibit several semetic phases and nematic phase, whereas the molecules with 4 benzene rings exhibit one semetic phase and nematic phase, and the molecule with 3 benzene rings exhibit only monotropic semectic phase.

  

摘要：Melt poly-condensation reaction has been applied for the synthesis of a new all-aromaitc thermotropic liquid crystalline polymer derived from 4-acetoxybenzoic, 4,4＇-diacetoxybiphenyl, 1,3-dibromobutane and terephthalic acid. All the obtained composites were chara-cterized by conventional spectroscopic methods. Their liquid crystalline behaviors and thermal properties of the all-aromatic polyesters were characterized with polarized optical microscopy(POM), thermogravimetric analysis, and differential scanning calorimetry(DSC).An obvious birefringence phenomenon with nematic texture was found. The wholly rigidity backbone aromatic series ester has a high glass transition,when substituent is leaded-in,the glass transition will reduce obviously.The mechanical properties of TLCP/GF had been improved greatly as the content of glass fiber was increased.Thats because glass fiber formed oriented structures and TLCP also show a self-fibrosis phenomenon.

  

摘要：Double-hexyl-trifluoro-alkyl benzene is a common liquid crystal monomer used in the thin film transistor liquid crystal and the first grade tiny twisted nematic liquid crystal. During the manufacturing process, its defluorinated impurity will inevitably appear. Therefore, MS analysis of the monomer and its impurity is highly essential in controlling the fluoride-losing impurity, thus increasing purity of the liquid crystal monomer. By comparing the mass spectrums of n-hexyl 3,5-double loop-2-fluorophenyl and propyl bicyclo hexyl-3,4-difluorophenyl, it is discovered that there are significant differences between the abundance ratio m/z 127 and 140 in the two mass spectra. The resonance forms of the two matials are compared, providing a reliable basis for the conform of the defluorinated impurities.

  

摘要：The hexamethylene alkyl benzene liquid crystal monomers are used in the Thin Film Transistor (TFT) liquid crystal, the first grade tiny Twisted Nematic (TN) and the Super Twisted Nematic (STN). The impurity affects resistivity,clearing points and the low temperature property of the mix liquid crystal a lot. In this work, the different polar gas chromatographic column and reversed-phase liquid chromatographic column are used to separate the cis-trans production to find the best column and the optimal analytical method. GC-MS is also used to determine the cis-product qualitatively.

  

摘要：Using urea, boric acid, and nitrates as the matrix and mixing a small amount of rare earth oxide, green long afterglow luminescent materials were synthesized at 600 ℃ by combustion method in high temperature resistance furnace. Furthermore, by incorporating the obtained phosphorous aluminates into organic host polystyrene, the flexible green-light-emitting long afterglow composite films was prepared. The composite films were characte-rized with the scanning electron microscopy and the fluorescence spectrum, respectively. The results show that the organic-inorganic composite films can be used as green-light-emitting rollable screens in the industry of information displays.  

摘要：The natural pitch effects on the response time and the electro-optic properties were theoretically researched in normal white general twist nematic liquid crystal display, including low-twist nematic liquid crystal display and high-twisted nematic liquid crystal display, and the electro-optic properties of the cell with various natural pitches were numerically simulated. The simulative results show that the response time is decreased as the natural pitch is decreased when cell gap is set as a constant, however, the on-state voltage is increased and the slope of electric-optic curve is gentle. Moreover, the response time is increased as the twist angle is increased, but the slope of electro-optic curve for the cell with higher twist angle is steeper than that of the cell with lower twist angle. The display properties of LCD were improved through considering the twist angle and the natural pitch together.

  

摘要：A new technique has been proposed to define and control the grain boundaries and domains of low temperature polycrystalline silicon (LTPS) films. It can be realized by combination of the solution process and the provision of nucleation sites (NS) and supplemental sites (SS). As a result, the crystallized poly-Si film has a much lower nickel concentration as compared to traditional metal induced lateral crystallization (MILC) poly-Si. High perfor-mance TFTs are obtained regardless of the position of the grain boundaries. Different shapes of domains can be obtained corresponding to different distributions of the NS and SS. Among the optimal designs, a honeycomb-like structure and a unidirectional structure are the most typical and practical. With the repeatedly regular distribution of the NS and the SS, domains of the same shape and size can be achieved. This process is precisely controllable and the crystallization time can be reduced to about 2 h at the annealing temperature of 590 ℃. The fabricated P-channel defined-grain (DG) poly-Si TFTs exhibited a maximum field effect mobility (μ_FE) of ~55 cm²/V·s, a subthreshold swing (S) of ~0.6 V/dec and a threshold voltage (V_th) of -3 V. The ratio of on-state to off-state drain currents is ~1×10⁷.  

摘要：Germanium carbide (Ge_1-xC_<em>x) films have numerous attractive properties, such as low stress and light absorption, good adhesion on many infrared substrates such as ZnS and Ge. In particular, their refractive index can be widely varied with composition within the range of 2~4. These excellent performances make Ge_1-xC_<em>x films promising candidates for applications in the field of multilayer antireflection and protection coating of IR window. Up to the present, some optical, electrical, and structural properties have already been reported for Ge_1-xC_<em>x films prepared by different deposition techniques. However, as regard the application of the Ge_1-xC_<em>x films for antireflection and protection coating of the IR ZnS window, the desired IR transmission performance has not been achieved, though the mechanical pro- perties of ZnS substrates overcoated by these durable Ge_1-xC_<em>x coatings have been significantly improved.In this work, an antireflective Ge_1-xC_<em>x double-layer coating, deposited on ZnS substrate via magnetron sputtering, has been developed. It is found that this Ge_1-xC_<em>x double -layer coating can significantly enhance the infrared transmittance in the interesting band of 8~12 μm and hardness of ZnS substrate, and it exhibits the excellent thermal stability and heat shock resistance. These results suggest that such a double-layer Ge_1-xC_<em>x can be used as an effective antireflection and protection coating for ZnS infrared window.  

摘要：With the conventional screen-printing process, the improved grid structure was fabricated using the mica plate as substrate materials. The carbon nanotubes were used as cold cathode materials and the soda-lime flat glass was adopted as packaging panel, so the mono-color triode FED device was developed. The electric-field intensity breakdown phenomenon for the grid substrate materials was avoided because of the good insulating perfor-mance. The effective distance between grid and cathode was decreased for the improved grid layer and the grid operating-voltage was also reduced. The display device possessed high displaying brightness, better grid control-ability and field emission characteristics.  

摘要：The laser induced liquid crystal molecular director reorientation are described by Euler-Lagrange equation, while the electromagnetic wave propagation in liquid crystal are described by Maxwell equation. By numerically resolving these equations, the mechanism of the laser induced director reorientation was studied. The threshold issue associated with the geometric parameters of the liquid crystal cell was discussed. It was indicated that the initial polarization state of incident laser took a role in the director reorientation. Then the effect of director reorientation on the polarization state of the light were compared, which is meaningful in the comprehension of the role played by the laser induced director reorientation in liquid crystal nonlinearities.  

摘要：The electric charges accumulation of liquid crystal display PI (polyimide) is part of dielectric theory of condensed physics. But, less-advanced dielectric physics theory fails to offer a clear explanation in the process of charge accumulation and release in liquid crystal display PI layer. The paper here analyzes accumulation of charges in liquid crystal PI layer through the use of the Maxwells equations, and then it analyzes the release of charges in the light of temporal-frequency spectrum in which the effect can be separated into fast charges and slow charges. Correlation is therefrom demonstrated between the permitivity and conductivity to PI layer and Liquid Crystal layer.The relationship between the release time of the slow charge and the thickness of PI is shown also.  

摘要：Effects of different cathode materials on OLEDs were researched in this paper. On the condition of the same function layers, five kinds OLEDs were prepared by using Al and Ca ∶ Al alloy (several alloys with different proportion of Ca and Al are adopted) as cathode with the structure of ITO/2T-NATA(15 nm)/NPB(25 nm)/Alq₃ ∶ C545T(20 nm)/Alq₃(30 nm)/Ca(X%) ∶ Al(100 nm) and ITO/2T-NATA(15 nm)/NPB(25 nm)/Alq₃ ∶ C545T(20 nm)/Alq₃(30 nm)/Al(100 nm).Current-voltage characteristic, luminescent-voltage characteristic, outer quantum efficiency, spectrogram characteristic of the devices were analyzed respectively. It is found that brightness of the device which was applied 10% Ca ∶ Al alloys as cathode reached the maximum value of 10 100 cd/m² and the best excellent efficiency. Spectrogram of devices with different Ca ∶ Al alloys as cathode, and spectrogram of devices with different drive current were discussed. Finally, how to choose cathode of OLEDs was described in theory.  

摘要：A new iridium(Ⅲ) complex Ir(NCPy)₂acac was studied based on reaction of iridium trichloride hydrate, 9-Naphthalen-1-yl-3-pyridin-2-yl-9H-carbazole with acetylacetone. Multiplayer-doped OLEDs were respectively fabricated based on Ir(NCPy)₂acac with electron transporting ability. The doping device showed strong saturated green electrophosphorescent emission, the emission peak wavelength 513 nm, brightness of 24 340 cd/m², current efficiency of 16.45 cd/A with Commission Internationale de LEclairage(CIE)coordinates of (0.26,0.62).This is the first report on new green phosphorescent material based on Ir(Ⅲ) complex.

  

摘要：Organic Light Emitting Diodes (OLEDs)with two emitters, doping DCJTB and C₅₄₅T into Alq₃ to form a double emitting layers respectively, were presented to investigate enhancement of doped emitter on performance of red organic light emitting diodes. The devices structure used are: Glass/ITO/4,4',4″-tris triphenylamine (2T-NATA)/N,N'-di(naphthalene-1-yl)-N,N'-diphenyl benzidine (NPB)/Tris-(8-hydroxyquinoline) aluminum (Alq₃) ∶ 4- (dicyanomethylene)-2-tert-butyl-6(1,7,7,7-tetrame thyljulolidin-4-yl-vinyl)-4H-pyran(DCJTB)/Alq₃ ∶ 10-(2-benzothiazolyl)-2,3,6,7- tetrahydro-1, 1,7,7,- tetramethyl-1H,5H,11H-(1)-benzopyropyrano-(6,7- 8-i,j)quinolizin-11-one (C₅₄₅T)/ Alq₃/LiF/Al, and the devices were compared with single emitting-layer red and green devices. The results indicated the red emission was indeed enhanced by the green emitter as comparing with the single emitting-layer red organic light emitting devices, and the optimal doping proportion for green emitter enhanced red device is ∶ (1.5%)DCJTB]/ ∶ (2.5%)C₅₄₅T](mass fraction),which exhibited a maximum brightness of 6 830 cd/m² at a voltage of 11.5 V, a maximum current efficiency of 4.59 cd/A at a voltage of 11 V, respectively, yet the means sacrifice the color purity of red light.  

摘要：The electroluminescent spectra and CIE coordinate variation of doping-type white organic light-emitting devices with Al/ LiF, Ca ∶ Al as cathode are analyzed under different driving current. The devices are respectively fabricated with the structure of ITO/2T-NATA/NPB/ADN ∶ TBP/Alq₃ ∶ DCJTB/Alq₃ ∶ C545T/LiF/Al and ITO/2T-NATA/NPB/ADN ∶ TBP/Alq₃ ∶ DCJTB/Alq₃ ∶ C545T/Ca ∶ Al. Additionally, the light emitting process was discussed according to the Direct Carrier Trapping (DCT) and Energy Transfer (ET) theory. The results indicated that two different devices have similar peaks position and they have no shift as the driving current increasing. But absolute spectra of device with Al/LiF as cathode is much more intensive under the same driving current; the device with Ca ∶ Al as cathode has much slighter variation of relative spectra and CIE coordinate when the driving current changed and can reach stable state under low driving current. It indicated that Ca ∶ Al cathode contribute much to the electroluminescent stability of organic light-emitting device.

  

摘要：A kind of blue OLED device with structure of ITO/2T-NATA(15 nm)/NPB(25 nm)/ADN ∶ TBP(30 nm, X%) /Alq₃ (30 nm)/LiF(1 nm)/Al(100 nm) was prepared via vacuum deposition process, here X varied from 0% to 5% with a step of 1%. The results showed that 2T-NATA function as the hole injection layer and dopant TBP can improve the luminance and efficiency, the 3% doped device exhibits a best performance including a maximum luminance of 5 840 cd/m² that was about 0.7 times than that of device without TBP; a maximum current efficiency of 5.29 cd/A, a luminance efficiency is 2 lm/W and CIE coordinates reach (0.152 9, 0.225 4) at 7 V.

  

摘要：In astronomical observation and space object detection,larger-aperture telescopes are used widely.Liquid crystal adaptive optics imaging technology has been used in correction of the aberration caused by atmospheric turbulence.In order to verify the validity of the technology,Zemax software and the optical components as few number as possible are used to design the compact type closed-loop liquid crystal adaptive optical system,and the characteristic of the system is evaluated.The specific tolerance principle is established.According to the tolerance analysis,it can be seen that the compact type adaptive optical system has a more relaxed tolerance conditions.And it is easier to achieve processing and alignment. We designed the compact type closed-loop liquid crystal adaptive optical system and make it match 1 200 mm telescope.The property of the whole system was evaluated correspondently.The focal length of the whole optical system is 19.13 m and the F number is 17.92.The peak-valve(P-V) value is 0.122λ.The RMS value is 0.031λ. The modulation transfer function(MTF) of the whole system is almost the same as the diffraction limited. MTF is 0.5 at 33 lp/mm.The limited resolution of the CCD is 31 lp/mm,we could see that the resources of CCD has been used effectively.

  

摘要：White organic light-emitting diodes with the structure of ITO/2T-NATA (20 nm)/NPBX(15 nm)/DPVBi(15 nm)/Alq₃ ∶ rubrene(10,x)nm/Alq₃(40 nm)/LiF(0.5 nm)/Al were demonstrated. The doping concentrations were 1%, 2%, 3%, 4% and 5%(mass fraction), respectively. In this structure, because the doping character of rubrene was full used, the characters of WOLEDs were better. The effect of the doping concentration on the EL color was firstly discussed, it was found that 3% doping offers the Commission International de LEclairage coordinates (0.32, 0.32) and high color stability. On this condition, the thickness of doping layer(Y) was studied, the thickness is 10, 15, 20, 25, 30 nm, respectively. With the increasing of the thickness, the yellow and blue emissions balanced for forming white EL color. When the thickness was 20 nm, the efficiency and brightness were optima, they are 5.10 cd/A and 17 130 cd/m², respectively.

  

摘要：It was inconvenient to display Chinese characters by the use of LCD in Proteus in the past.Firstly, the character module software must be used to pick up the character models, and then, the dot matrix data would be copied to the program. Not only the steps were cumbersome, but also only inherent characters could be showed. In this paper, Chinese character library HZK16 was loaded in program memory AT24C512 in Proteus, the data acquisition circuit was designed, and the display of Chinese characters was realized by using LCD PG160128 in Proteus. Experimental results show that it is convenient to display Chinese characters by the use of AT24C512 storing Chinese character library, the mode has been broken that only fixed Chinese characters can be showed,and the development efficiency is improved.

  

摘要：The paper introduces the design of a kind of video processor with the function of auto-focusing. The video processor receives digital YCbCr video signal. Utilizing a piece of DDR2 SDRAM as frame buffer, the video processor realizes the function of format conversion, frame up-scaling and color space conversion. The paper proposes and realizes an improved gray scale differential auto-focus algorithm and calculates the focus value of the current image real-timely. The mountain climbing searching strategy is applied to control the moving of the focus motor, and the auto-focusing of image is realized. The whole design is realized in VHDL and verified with Xilinx XUPV5-LX110T FPGA developing board.

  

摘要：A novel frame buffer pixel circuit was developed which acquires low power inside a pixel. The function timing and power of this novel pixel circuit was evaluated by SPICE simulation. A voltage comparator embedded in a pixel compares the adjacent frame data voltage by which the intelligent discharge operation was realized. This intelligent discharge operation lowers the power dissipation in LCoS backplane.

  

摘要：The technology on scale control is becoming more maturing in LED display which has been mostly digitization these days. The original method of luminance and scale test has become an obsolete stock and the new measurement means must be developed. The paper analyzed the relation function between image data and grayscale which can indicated and gives the method for the scale measurement technic in LED display. Experimental result indicates that the method which obtained the relation function from the scale control level based on the statistics of incremental rate of gray difference can achieve the desired effect.

  

摘要：With the continuous development of embedded systems,power measurement and control instrument is also a great development. Keyboard and LCD as the intermediary between users and systems are generally used in computer systems. This paper presents a multi-level in the power measurement and control instrument characters displayed in the menu structure design and gives a detailed implementation method. Through the embedded LINUX platform by the C language program written in a vivid demonstration examples, the dot-matrix LCD display and keyboard operation of the software design methodology are revealed.

  

摘要：A real-time wireless remoting monitor terminal is designed based on the ARM platform and embedded Linux OS with mature GPRS/GSM technology. The MC39i module for AT commands protocol and protocol data unit (PDU) for encoding and decoding process are discussed in detail, the implementation method between MC39i module and terminal device is provided under Linux.The GUI will greatly improve the efficiency of human-device interaction, then this paper focuses on how to establish the development environment of QT/Embedded and how to porting an application to mobile terminal. The effect is proved to be well in practice.

  

摘要：This paper presents an FPGA-based LED display control system design method. The system is composed of an FPGA chip and an LED display module and interface drive circuits. The system uses EP2C35F672C8 FPGA chip with an embedded Nios Ⅱ soft-core microprocessor. The communication between the PC host computer and FPGA core board uses the RS232 serial and JTAG download cable. Through the display driver module, the output of the FPGA core board lit LED dot matrix display driver module. The MAX232 chip is used for serial communication interface circuit and four 74HC595 shift register are used for the output driver circuit. Compared with the traditional LED display system with SCM control, this system has many advantages, such as,the simple external circuit, being easy to upgrade and good stability.

  

摘要：A design of OSD technology to overlap the characters and pictures in the TV signal based on FPGA controller is introduced in this paper . The data of overlapped characters and pictures are stored in the ROM of FPGA, the times are generated by FPGA inner logic circuit to control the switch of TV channels to finish the overlapping work. The design has the advantages of simple code framework, good expansibility, convenient changing the display position. The results that the circuit works stably, and character phase wobbles little, were testified by using the method which can be widedly used in the OSD field.

  

摘要：This paper analyzed the properties and the bus interface of industrial processor used frequently in current industry,and proposed a TFT-LCD driver scheme which could be used by kinds of processors or their interface bus, then developed this multi-communication-interface industrial TFT LCD controller harware system.The correctness of this system are verified by using the technology of FPGA and SOPC,so a multi-communication-interface,high-performance and low-price industrial human-computer exchange module was finished.

  

摘要：Abnormal running of the motor would cause its temperature changing. The pixel gray values of a infrared image can reflect the relative temperature levels of the object. It is a good diagnosis method to obtain the motor temperature levels via the luminance variation of the motor infrared image. But the infrared images obtained by the IR imaging sensor are low contrast, and serious noisy, therefore, it is necessary to enhance the IR images. Based on wavelet and weighted filtering, a novel enhancement method is proposed in this paper,this algorithm could retain high and low frequency information well. The results show that this enhancement algorithm has excellent image enhancing function and visual effect.

  

摘要：The contrast detection threshold under the darkroom, three kinds of common lamplights and the room natural environment are obtained by viewing the gratings displayed on a CRT with the same parameter. CSF of human vision system under daily life environment is obtained. Measurement results are compared with foreign previous ones. The effect of environment brightness on the contrast sensitivity of human vision system is studied.

  

摘要：An algorithm based on the threshold of image Cumulative Distribution Function(CDF) for dynamic backlight LCD-TVs was proposed in this paper. The backlight luminance can be dimmed to reduce the backlight power consumption and enhance the contrast. The distortion of the display image could be controlled through this method so that the image quality can be improved effectively. A circuit for this method was designed to proved that the method was feasible.

  

摘要：The moving target detecting technology based on the in-door background was studied in this paper. Various kinds of object detecting algorithms were discussed, and the object detecting algorithm based on relatively immobile in-door background was put forward. The Gauss background modeling was used to distill perfect background frame which could be adaptive updated. Then the subtraction between the background frame and current frame was made to get the foreground of moving target in the video. Finally, the ideal target detecting result could be obtained after the noise was smoothed and eliminated.