Photoacoutic detection system of solid powder and signal analysis methods,which are used to distinguish material component quickly without damage and improve detection ability,are researched. Nonresonant cylinder photoacoutic cell is designed based on the theory of R-G. The system consists of high power xenon lamp,chopper,lock-in amplifier,grating monochromator,data acquisition system and photoacoustic cell. The methods of enhancing the amplitude of signal are used to improve resolution ability,such as choosing high sensitivity sound detector,increasing permeation rate,designing low noise and high signa-to-noise ratio circuit. The experimental system is stable and reliable. Wavelet is applied to improving analysis ability. It provides identification evidence conveniently and quickly by the photoacoustic signal analysis of nitrocompound,copper sulphate and mixture.

A new hybrid optical switching network based on protection resource named P_HyLABS is presented. P_HyLABS takes advantage of the protection resource (wavelength channels) in optical circuit switching (OCS) network to construct optical burst switching (OBS) network layer,which is combined with the OCS layer into hybrid OBS/OCS switching network. Simulation results show that compared with pure OCS network and OBS network,P_HyLABS takes advantage of the circuit-switched connection of OCS and the statistic multiplexing characteristic of OBS,achieves higher transportation efficiency,accommodates the bursty traffic efficiently and restores part of data transmission even in the case of multiple failures.

The bit error rate (BER) of optical code-division multiple-access (OCDMA) system is an important index of evaluating system performance because it can reflect the premise of considering dispersion and nonlinear effect broadening in single-mode fibers. Based on the definition of BER in ideal condition,the influences of third-order dispersion (TOD) and third-order nonlinear on the BER are introduced and the BER of OCDMA system with optical hard-limiter (OHL) and 2D OCDMA system is analysed. The results show that BER will increase under the action of TOD and third-order nonlinear which has lower effect on system performance than TOD,and at the same time the performance of transmission system with OHL and using two-dimensional code will be improved under the same fiber condition.

When imaging a scene through a glass,the image is a linear superposition of a real image observed through a glass and a virtual image reflected on it. This brings adverse effect on image processing,computer vision,etc. Reflective separation can be done by the original method of blind separation,nonlinearity in the course of imaging will degrade precision of separating reflections using linear independent component analysis. Kernel independent component analysis (KICA) can effectively deal with the nonlinearity. The reflections is removed by using FastKICA based on the Hilbert-Schmidt independence criterion. Experiments show that FastKICA is more effective than linear independent component analysis and conventional KICA.

A large number of continuous speckle images with different processing techniques and different surface roughness are taken using the laser speckle measurement method. Through the texture analysis method based on gray-level co-occurrence matrix,four characteristic parameters of the images,angle of second-order moment,moment of inertia,relevance and entropy are calculated and analyzed. The research indicates that,the parameters values of the continuous laser speckle images are stable with little fluctuation and the regular relationship curves of the parameters and surface roughness are testified and verified. Outside interference and dynamic uncertainty of the device over time are eliminated,making results more reliable. The relation database of the parameters and surface roughness is expanded at the same time,and laser speckle measurement method having high precision measurement of surface roughness is testified.

A new self-adaptive multi-sensor image fusion algorithm based on Curvelet transform is proposed. Full-color and multispectral images are decomposed and transformed using the algorithm,and different fusion rules are selected according to different frequency characteristics. Self-adpative regional energy coefficients fusion rule and regional feature self-adaptive fusion rule are selected for low- and high-frequency coefficients. The final fusion image is obtained by reconstruction. Compared with other fusion algorithms this algorithm is a feasible and effective image fusion algorithm.

The imaging resolution of all ground-based telescopes is severely limited by the effects of atmospheric turbulence,especially for imaging the extended objects. The lucky imaging technique is an image post-processing method based on selecting-recentring-coadding of sequence short-exposure images of objects,which can reduce the influence of image quality because of turbulence-induced imaging motion-blur restoration and reduce the resolution loss. The basic theory and flow of lucky imaging are introduced,and then this technique is used on the data of experimental observation of extended objects through atmospheric turbulence. The results show that the lucky imaging technique can improve the imaging resolution of extended objects through atmospheric turbulence.

A Laplace and generalized Gaussian mixture distribution-based method is proposed to explore the nonsubsampled Contourlet transform (NSCT) coefficients. The investigating result reveals that the NSCT,as a shift-invariant contourlet transform,obtains redundant coefficients in each scale and each direction,and its coefficients differ from those of Contourlet transform in aspects of general Gaussian distribution. The regularized parameters should be introduced to generalized Gaussian distribution model to enhance the coefficients distribution. The medical image denoising experimental results with comparison to similar Contourlet-based methods indicate the proposed modeling method improves the accuracy of noise estimation,increases the peak signal-noise ratio,and achieves better visual quality.

An adaptive normalized convolution super-resolution algorithm based on edge detection and Keren registration method is proposed. To further improve registration precision of low-resolution image sequences,we combine Keren registration method with edge detection in the algorithm. Firstly,the edge feature of image sequences is extracted by Roberts operator. Then the registration parameters between edge feature images are obtained by Keren improvement registration method which is based on four parameters affine transformation model. The results of simulation experiment show that if the image edge detection is introduced before the Keren algorithm,the registration precision will be increased greatly even though there are noises and large rotation between images sequences. And a higher precision can be obtained by using Roberts operator compared with other traditional operators. Finally,the adaptive normalized convolution super-resolution fusion algorithm is used to reconstruct high-resolution image from low-resolution image sequences. Excellent reconstruction capability of the super-resolution algorithm based on the proposed registration method is demonstrated through an experimental real aliased image sequences.

Photon-transfer technique for single pixel is developed to measure the readout noise and gain of CMOS imager in consideration of its special structure. The methods to evaluate the linearity,well capacity,dark current,pixel non-uniformity and quantum efficiency are also discussed. At last,evaluation test is carried out based on a 2 k×2 k CMOS sensor. The experiments show that the evaluation method is feasible and reliable.

By focusing laser pulses with wavelength 1064 nm and pulse width 8 ns into FC-72 medium,the intensity distribution of backward stimulated Brillouin scattering (SBS) spot is investigated experimentally by CCD camera. The images are analyzed by digital image processing technology to obtain the spatial intensity profile and evolution of SBS spot. Using the image processing toolbox of MATLAB,the noise removing treatment on original CCD image of laser spot is performed. And the smoothing treatment on intensity distribution curve is achieved by using the curve fitting and FFT smoothing functions of Origin software. The results show that the noise of original image is effectively suppressed and ridded after the preprocessing treatment,and the intensity distribution is comparatively smooth. On the condition that the pump beam is of Gaussian profile,the intensity distribution of SBS spot is changed from quasi-Gaussian to Gaussian profile when the pump energy increases.

A compact TE/TM polarization beam splitter (PBS) based on a silicon-on-insulator (SOI) ridge nanowire directional coupler is designed and optimized by using a finite-element method (FEM) and a finite difference time domain (FDTD) method. Considering the fabrication precision and the mode mismatching loss in a directional coupler,a gap width about 100 nm is chosen. The ridge height,the ridge width and the gap of two parallel nanowires are optimized to have the shortest length for the polarization splitter. The numerical simulations show that the optimized PBS has a short length of about 17.3 μm,and the waveguide width has a fabrication tolerance of about－20-10 nm,and the bandwidth is about 50 nm when the extinction ratios for both polarizations are larger than 15 dB.

Subwavelength hole array vertical-cavity surface-emitting laser (VCSEL) is fabricated based on high power 980 nm VCSEL. The far-field output power reaches 1 mW. The special fabrication process is introduced and the characteristic of the device is also analyzed.

The control scheme of all-digital laser gyro is presented,and the laser gyro of the full digital control,digital ring laser gyro,is implemented. The principle and structure between the analog laser gyro and digital laser gyro are compared,and the advantages and key technologies of digital gyro are described in detail. In particular,jitter-driven pulse-width modulation waveform and graphical test data of the digital gyro is given. It is proved that the digital gyro direction of development in line with the ring laser gyro,improves debugging and production efficiency,and simplifies the requirements for navigation systems.

Based on the study on femtosecond laser interaction with metal materials,with different laser operating parameters,micro-arrays pores are processed on aluminum foil with femtosecond laser. The relationship between the aperture of aluminum foil processing micro-arrays pores and the laser parameter is studied. Origin7.0 and SPSS 13.0 are used to analyse experimental data by graphs. The influences of femtosecond laser pulse number,pulse width,single pulse energy on the aperture sizes are indication.

As the fluorine atom generator,the discharge tube plays an important role in discharge-driven CW HF/DF chemical laser system. The discharge scheme widely employed currently is the high voltage DC power which uses ballast resistor to restrict current and the typical electrical parameter scales are several kilovolt and hundred milliampere. The traditional theory and results of experiments indicate that yield rate of fluorine atom is proportional to the input power of discharge tube; accordingly the laser power is proportional to the input electric power. Using resistances of different levels,for the same input power the scheme of low voltage and large current is easier to gain high laser power output than that of high voltage and low current.

A feature-based two-step local stereo matching with high efficiency is presented to eliminate the ambiguity of binocular stereo problem in medical optics. The local binary pattern/constrast (LBP/C) textures describing local features are firstly analyzed for both stereo pairs,and the initial matching costs is constructed from the features. Two-pass aggregation with adaptive support weight (ASW) for the costs are adopted only in the vertical and horizontal directions,which efficiently resolves ambiguity in feature matching. Initial disparity map is obtained via local Winner-Takes-All optimization from them. To solve the ambiguity from other aspects including textureless,repetitive patterns and occlusion etc.,disparity refining procedure consists sequentially of three steps:two-pass ASW-based disparity calibration,warping-based occlusion detection and epipolar-line-based least square fitting to handle occlusion. The experimental results indicate that this approach with texture cues and low complexity has high efficiency and concise structure,being easily implemented and eliminting ambiguity,so that it can obtain comparably accurate and piecewise smooth dense disparity map effectively.

The Ba5CaAl4O12:Tb3+ phosphor was synthesized by high temperature solid state reaction,and its luminescent properties were investigated. The emission spectrum of Ba5CaAl4O12:Tb3+ excited by 239 nm light shows four major emission peaks locating at 489,543,550,587 and 623 nm corresponding to the 5D4→7F6,5D4→7F5,5D4→7F4 and 5D4→7F3 typical transitions of Tb3+,respectively. The UV excitation spectra indicates that the host absorption is located at about 240 nm. The effect of the molar concentration Tb3+ on the emission intensity is studied. The result shows that the emission spectrum intensity reaches the maximum value when the mole fraction of Tb3+ is 4%. Fluxing H3BO3 and NH4Cl on the sample increases the luminescent intensity in various degree. The emission spectrum intensity increases with increasing the H3BO3 and NH4Cl concentration,and then decreases. Compared with the fluxing H3BO3,the NH4Cl can enhanced the luminescent intensity better.

A new plate-type high power LED illuminator with louvers is designed. It has the features of light weight,small size,beautiful appearance,modularization and reconfiguration. Aluminum plate with high thermal conductivity is applied as radiated circuit plate for high power LEDs,and aluminum stack with 0.4 mm thickness as radiated fins,which make illuminator module with input power 21 W combining with micro grooved heat pipe. The illuminator module is integrated with lightening and radiating. According to lumination requirements,module groups can be reconstructed into illuminators with different input power. Theoretical analysis and experimental research were conducted to a 144 W illuminator. Calculated results indicate the calorific value of one module is 18 W and the heat transfer value is 47 W. The simulated results indicate that the max junction temperature (Ta) of LED chips is 75 ℃ and Ta measured by experiment is 75.7 ℃ when ambient temperature is 30 ℃ and natural convection heat transfer coefficient 10 W/(m2·K). Theoretical calculation and simulated results show that the illuminator has a good prospect of application and can be used as street lamp,square headlight and so on.

A multi-color projection scheme based on single grating light modulator (GLM) using three-color lasers as light source is proposed. First,the principle of color display is explained. Second,red,green and blue laser composing standard D65 white light source is analyzed by colorimetry theory,considering three important indicators,displaying reduction degree of color,displaying brightness and output power of laser. The laser light source is analyzed and optimized. The result indicates that the combination of the lasers with wavelengths of 635,532 and 457 nm is the best optimal project. The experiment system is set up,and the color projection experiment based on static grating light modulators is carried out by collecting the ±1st order diffraction light. Red,green,blue and white projection pattern is obtained through the experiment,which preliminarily proves the validity of this color projection scheme.

White organic light-emitting devices were fabricated by 9,10-bis (2-naphthyl) anthracene (ADN) doped with rubrene. Multilayer organic devices using AND and rubrene as an emitting layer produce white emissions with good chromaticity and current efficiency of 5.93 cd/A at 140 mA/cm2. A maximum luminance of 9300 cd/m2 is obtained at the driving voltage of 21 V. The Commission Internationale de L’Eclairage coordinates of the white emission are in the white zone (0.32,0.40). This performance can be explained by F?rster energy transfer from the blue-emitting host to the orange-emitting dopant.

A coupling field is introduced into the L -three-level scheme driven by a coupling field and a probe field,and then the L -three-level scheme is driven by two coupling fields. The probing absorption spectrum is researched in theory by solving the density matrix equation of motion. The spectrum is characterized by a series of doublets when the Rabi frequencies of the two coupling fields are equal where one coupling field is exactly resonant with the transition and the other is detuning with the transition. The positions of peaks are dicussed. These situation is interpreted well by dressed states.

By contrast with solid and chemical laser,the laser diode pumped alkali laser (DPAL) has shown great predominance and potential because of its extremely high quantum efficiency,outstanding heat dissipation ability,high beam quality,no limit of single aperture power scaling and safe operation. The basic principle and recent research development of DPAL are introduced,the obstacles and solutions of high power scaling of DPAL are analysed,and the expectation of DPAL development is made.

Metamaterials have artificially structured composite and novel electromagnetic properties not available in natural materials. The electromagnetic response of metamaterials can be tuned flexibly,and this is especially important for the terahertz (THz) technology. The realization and development of THz metamaterials provide an opportunity for the development and application of THz technology. The research progresses on the metamaterials at THz are summarized,including design,preparation,functional devices and other applications.

A wide-band spectrum optical film thickness monitoring system with compound light path is introduced. The structure,components and working principles of the system are analyzed. The monitoring system is developed by increasing a piece of spectroscope with aperture to form compound light path,and wide-band spectrum monitoring software based on LabVIEW. Methods of wide-band spectrum optical film thickness monitoring based spectrum scanning method and optical film thickness monitoring based on extremum method are compatible. The accuracy and automatization of optical film thickness monitoring can be improved also. This monitoring system can be used in upgrade or reconstruction of optical coating devices.