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Abstract:A new rare earth complex Tb(p-CIBA)₃phen was synthesized and introduced into organic light emitting devices (OLEDs) as emitting material. The Tb(p-CIBA)₃phen was doped into PVK to improve the film-forming and hole-transporting property. Two kinds of devices were fabricated. The device structure is as the following. Single-layer device: ITO/PVK: Tb(p-CIBA)₃phen/LiF/Al; double-layer device: ITO/PVK: Tb(p-CIBA)₃phen/AIQ/LiF/Al. The performances of both devices were investigated carefully. We found that the emission of PVK was completely restrained, and only the green emission was observed from the electroluminescence. The full width at half maximum (FWHM) was less than 10 nm. The highest EL brightness of the single-layer device is 25.4 cd/cm² at a fixed bias of 18 V, and the highest EL brightness of the double-layer device reaches 234.8 cd/cm² at a voltage of 20 V. Supported by National Natural Science Foundation of China (90 201004), Beijing Science and Technology Foundation (H0304300 20410) and Hebei provice Natural Science Foundation (203148).

Abstract:A new modulator for the optical signal in a fiber based on multi-beam interference is designed. In the experiment,the distance of a couple of abutted fibers was modulated through a piezoelectric ceramic pipe driven by 50 Hz AC voltage,so that the amplitude of the transmitted optical signal was modulated. The modulation ratio is about 10% ,S/N ratio is about 60 dB and the bandwidth is about 200 KHz.

Abstract:A novel torsion sensor, which can be embedded in the engineering material, is proposed. Based on the coupled mode theory and the characteristic of twisted high birefringence fiber, we have established the mathematical model of twisted high birefringence fiber grating transfer matrix. Two numerical simulation methods based on the transfer matrix method and coupled mode theory were used to analyze the consequent changes in reflection spectra. The simulation results of the two methods show good agreement with each other. The two main peak wavelengths of the high birefringence fiber grating shift as the twist angle changes from 0 to 360. And a peak was produced among the wavelengths of two main peaks. Its wavelength basically does not change and is about 1552.225 nm. Its corresponding reflected peak valueR _c basically presents the linear relationship with the twist angle α. The experiments show that the system has a wide measurement range. The resolution is 0.012° and the sensitivity is 0.13/rad. Good agreements between experimental results and numerical simulations have been obtained. Supported by National Natural Science Foundation of China (60377002)

Abstract:A new type of highly nonlinear photonic bandgap fiber with modified honeycomb lattice is brought forward. Based on full-vector plane-wave method, the structure of bandgaps and the distributions of fundamental mode field are analyzed. Then its nonlinear coefficient is calculated, and the effect of each structural pa- rameter on the nonlinear coefficient is discussed. At last, considering many factors synthetically, we make some optimization design of the structural parameters. It can be concluded that this new type of photonic bandgap fiber can gain the nonlinear coefficient of 30 W^-1 km^-1.

Abstract:A highly efficient and high power green laser generated by intracavity frequency doubling of a diode-sidepumped Q-switched Nd: YAG laser has been demonstrated. In the simple L-shaped cavity geometry, the maximum green output power of 28.5 W was obtained with a pulse width of 95 ns at a pulse repetition rate of 10 kHz by using a LBO crystal for frequency doubling, corresponding to a conversion efficiency of 11% from diode pump power to pulse green power. At a pulse repetition rate of 1. kHz, 6.9 mJ of pulse energy, 25 ns of pulse duration and 276 kW of peak power were obtained. This work was supported by the National Natural Science Foundation of China (Grant No: 60478009)

Abstract:We theoretically analyze the reflection spectra of the fiber Bragg gratings in the quadratic strain field,and resolve the numerical value with transfer matrix method. When the value of pressure is changed,we can obtain diverse reflection spectra of the fiber Bragg gratings,which is in good accordance with the experimental results.

Abstract:A Smith-Purcell (SP) free electron laser (FEL), composed of a metallic diffraction flat grating, an open cylindrical mirror cavity and a relativistic sheet electron beam with moderate energy, is presented. The characteristics of this device are studied by theoretical analysis, experimental measurements and particle-in-cell (PIC) simulation method. Results indicate that the coherent radiation with an output peak power up to 50 MW at millimeter wavelengths can be generated by using relativistic electron beam of moderate energy

Abstract:In this paper,nanosecond pulsed laser is introduced to selectively ablate away indium tin oxide film and metal film without destroying the underlying layers for fabricating organic light-emitting diodes. By varying density of energy,pulse number and width of the laser,the influence on morphology of the laser trenches of indium tin oxide and metal films are investigated. It is presented that uniform ablation trench can be obtained with 16 laser pulses at 0.15 J/cm^2 for aluminum film and 10 laser pulses at 0.65 J/cm^2 for indium tin oxide film. It is found that the characteristics of the organic light-emitting diodes prepared with laser ablation are almost the same as those of that prepared with conventional patterning method.

Abstract:Apodisation technology is introduced to optimize fiber Bragg grating based on the analysis of reflectivity spectrum and group delay response of fiber Bragg gratings. The characteristics of Hamming, Gauss and super-Gauss functions are discussed and the optimization effects of the three apodisation functions on ripple smoothness of reflectivity spectrum, group delay and linear degree are compared respectively. As a result, the optimization effects of Hamming function is better than other two functions. When the bandwidth is less than 1dB, Super-Gauss function is the best choice and proper parameters (G and m) of super-Gauss function can be selected expediently for wider bandwidth and better ripple smoothness of reflectivity spectrum.

Abstract:A new kind of lidar signal light-splitting system is presented to sum up different rotational Raman lines and to improve the signal to noise ratio (SNR). The temperature parameters with high SNR of this new system have been obtained with a normal laser and a small telescope from several kilometers.

Abstract:A novel high magnification zoom laser beam expander is proposed originally. The zoom part and fixed part of the beam expander both adopt spherical lens and the compensation part comprising a spherical surface and an aspherical surface. The structure parameters were given by using geometry optics. The zoom characteristic and image quality were also analyzed. The results show that the magnification of the beam expander can be adjusted continuously from 3 to 20. Compared with other congener spherical zoom system, the beam expander has the advantages of high magnification, compact structure, high beam quality and high transmission efficiency. The novel expander can be used in many fields effectively.

Abstract:Mn-doped ZnO diluted magnetic semiconductor nanoparticles are prepared by an ultrasonic assisted solgel process. Transmission electron microscopy shows pseudo-hexagonal nanoparticles with an average size of about 24 nm. From the analysis of X-ray diffraction,the Mn-doped ZnO nanoparticles are identified to be a wurtzite structure without any impurity phases. The magnetic properties are measured by using superconducting quantum interference device. For the ZnO with 2 % Mn doping concentration, a good hysteresis loop indicates fine ferromagnetism with a Curie temperature higher than 350 K.

Abstract:The electro-optic properties of a poled second-order nonlinear optical maleimide polymer system were reported. This polymer was synthesized by doping disperse red 1 moieties into the maleimide system as the side chains. Its glass transition temperature was measured to be 202°C by Differential Scanning Calorimetry (DSC) technology. After being poled, the measured electro-optic coefficient of PHSD at the wavelength of 1550 nm is as large as 3. 03 pm/v. Except for an initial decay after being poled, PHSD exhibits little electro-optic relaxation in a long term and its electro-optic coefficient remains about 2. 46 pm/v after 15 days. This work is partially supported by National Natural Science Foundation of China (Grant No: 60377013, 60507013) and WHUT Foundation (XJJ2005175).

Abstract:We present a novel algorithm of finding cycles, called the Fast Cycles Mining Algorithm (FCMA), for efficient p-cycle network design in WDM networks. The algorithm is also flexible in that the number and the length of cycles generated are controlled by several input parameters. The problem of wavelength assignment on p-cycle is considered in the algorithm. This algorithm is scalable and especially suitable for survivable WDM mesh networks. Finally, the performance of the algorithm is gauged by running on some real world network topologies. Supported by the National Natural Science Foundation of China (NSFC) (grant 60302010)

Abstract:A layered network model for optical transport networks is proposed in this paper, which involves IP, SDH and WDM layers. The strategy of Dynamic Joint Routing and Resource Allocation (DJRRA) and its algorithm description are also presented for the proposed layered network model. DJRRA optimizes the bandwidth usage of interface links between different layers and the logic links inside all layers. The simulation results show that in contrast to the classical separate sequential routing and resource allocation solutions, DJRRA can reduce the blocking probability and increase network throughput effectively. Supported by the Science & Technology Fund of Huawei Ltd. (No. YJCB2005040SW) and Postgraduate Creation Fund of Xidian University (No. 05030).

Abstract:Optical interconnection between LSIC (Large Scale integrated circuit) is an increasing demand as data communication is growing very fast, whereas electronic interconnection could hardly satisfy the fast-growing request of data rate. A realization of on-board optical connection is described in this paper, of which multimode fibers were buried into the RF4 board by cutting grooves on the surface of the board with a LPKF ProtoMat95sll, and two MT connectors were reconstructed to form an input-and-output couple in the board. Optical transmission at 2.5 Gbit/s×12 channels data rate was demonstrated and a widely opening eye pattern was achieved. Large scale prototype of dense-multimode-fiber-embedded board for the backplane application was also fabricated by using the methods mentioned in this paper.

Abstract:In this letter a cascade quantum teleportation scheme is proposed. The proposed scheme needs less local quantum operations than those of quantum multi-teleportation. A quantum teleportation scheme based on entanglement swapping is presented and compared with the cascade quantum teleportation scheme. Those two schemes can effectively teleport quantum information and extend the distance of quantum communication.

Abstract:A new analytical method for improving the performance of a network attached optical jukebox is presented by means of artificial neural networks. Through analyzing operation (request) process in this system, the mathematics model and algorithm are built for this storage system, and then a classified method based on artificial neural networks for this system is proposed. Simulation results testified the feasibility and validity of the proposed method that it could overcome the drawbacks of the frequent I/O operation and provide an effective way for using the Network Attached Optical Jukebox.

Abstract:The gray level values of target pixels of infrared images processed by the SUSAN noise filtering algorithm and the background filtering algorithm are calculated,assuming that the target distance is given in image acquisition. The equivalent blackbody temperature is obtained by the temperature calibration model that represents the quantitative relation, at a certain integration time, between the gray level value and the equivalent blackbody temperature. The temperature calibration model has been acquired by the curve fitting with the experimental data of blackbody temperature calibration using Origin 6.0. Then the target radiance can be determined by the radiant flux equivalence model built on condition that the target radiant flux received by the infrared detector is equivalent to that of the blackbody placed in front of the infrared detector at a close distance. This measuring method is based on the temperature calibration parameters and real image information,so it can avoid subjectivity of the traditional theory modeling methods.

Abstract:In this paper,a digital holography system with short-coherence light source is used to record a series of holograms of a micro-object. The three dimensional reconstruction is completed by the least-square-polynomial-fitting with a series of two dimensional intensity images which are obtained through holographic reconstruction. This three dimensional reconstruction method can be used to carry out three-dimensional reconstruction of a micro-object with strong laser speckle noise, which can not be obtained from the conventional method.

Abstract:Image pattern recognition is the most i mportant re-search directions currently,and feature extraction is itscoretechnology.Researchinthisfield dates backat leastto the 1940s ,but most feature extraction techniques re-quire users to give a priori probabil…

Abstract:It is shown that, in an open ladder-type atomic system with spontaneously generated coherence (SGC), regardless of the existence of an incoherent pumping, a lasing without inversion (LWI) gain is always remarkable larger than in the system without SGC, by adjusting the strength of SGC. Moreover, LWI gain in the system without incoherent pumping is much larger than that with incoherent pumping, within some strength of SGC; while in the corresponding closed system with SGC, we can't obtain LWI gain at any strength of SGC, if no incoherent pumping is applied.

Abstract:Compared with direct ablation, a prepulse is used to enhance the coupling coefficient in laser plasma propulsion. It is found that the coupling coefficient is related with the delay times between the main beam and the prepulse. At a delay time of 12 ns, the coupling coefficient reaches the maximum of 5.8 × 10^?5 N/W.

Abstract:A DSP-based control system for laser processing that enables the motion of laser beam in two dimensions,and the control of its power with PC or without PC is discussed. The operation and implementa- tion of the control system along with the rapid processing of image data are presented. The purpose of the control system is to operate the laser equipments in such a manner that various programmable laser control signals are available for vector and bitmap processing of characters and pictures. This control system makes the laser processing more intelligent and flexible and can be used for welding,marking and engraving by lasers.

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Abstract:No .1Devices and Applications0001 Design of photonic crystal fibers with anomalous dis-persionCHI Hao , ZHANG Xian-min , and SHENLin-fang0005 Characteristics of surface and interface for ITO/PTC-DA/p-Si thin fil mdeviceZHENG Dai-shun , ZHANG Xu , and QIAN…