The drive mode of MEMS deformable micro-mirror is initially selected. Based on theoretical analysis of optics and mechanics characteristics of MEMS deformable micro-mirror, the relation between correlation structure parameter and performance of deformable mirror is obtained according to the requirements which compensate thermally induced aberration of laser diode. Pumped solid-state laser, a novel electrostatic actuated deformable micro-mirror with continuous facet is designed. It is used to set up a closed-loop control adaptive optics system, which has compensated thermally induced aberration of laser beam. The experimental result shows the intra-cavity aberration was effectively compensated and the output power and beam quality were improved by the novel MEMS deformable micro-mirror.

Based on the two-center nonvolatile holographic recording method and the theory model combining band transport model with the two-dimensional coupled-wave equations, the numerical simulation method is used to study the photorefractive formation and diffractive properties of the crossed-beam photorefractive gratings. The influence of the intensity change of sensitizing ultraviolet (UV) light and the total intensity change of the recording red light on nonvolatile crossed-beam photorefractive gratings in LiNbO3:Fe:Mn crystals is investigated. And the results, including the average refractive index modulation, the spatial distribution of the diffracted intensity and the diffracted efficiency at the fixing end, are obtained. When the UV light intensity increases under fixed red light intensity, the average refractive index modulation increases accordingly, the spatial distribution of the diffracted intensity is almost unchanged and the diffraction efficiency increases firstly and then decreases. There is an optimal intensity for the sensitizing UV light to achieve the maximum diffraction efficiency (higher than 80%). When the intensity of the sensitizing UV light is fixed, with increasing recording red light intensity, the index grating recorded wears off, the spatial distribution of the diffracted intensity is more and more homogeneous, and the diffraction efficiency decreases.

Based on Kogelnik’s one-dimensional coupled-wave theory and dispersed Fourier transform, the diffractive characteristic of two pieces of volume phase gratings, which are cascaded and having orthogonal grating vectors for the continuous-wave (CW) laser beam, is analyzed. The cascaded gratings’ low-pass spatial filtering for CW laser beam is performed. And the performance of its filtering for deformed Gaussian laser beam is simulated. The results show that with the fine angular selectivity of volume grating, the component of the larger quantity in angular spectrum domain can be deleted directly without focusing the laser beam. The distribution of intensity of diffractive laser beam is similar to that of the undeformed one in spatial domain. So the low-pass spatial filtering for CW laser beam is realized. This novel method can eliminate the drawbacks of pin-hole filter, which focuses the laser beam, enhances its intensity in the focal plane, and probably damages the stuff vicinal to the pin hole. So it may take the role of the pin-hole filter, especially in the high-power laser field.

The effect the diffractive optical characteristic by the surface bending of two-dimensional grating light modulator (GLM) is disaused. Based on the measured surface structure data, an array model was built, and the effect on diffractive light distribution in spectrum plane with different bendings was calculated by Matlab software. The relation between bending and contrast was deduced. The result indicates that the surface bending can affect the image contrast greatly in condition of darkness. If the bending in center is reduced less than 0.1λ, the contrast will be larger than 1000. An optimized scheme is proposed for reducing the bending of the grating. Through a dynamical experiment which shows the modulation effect of brightness and darkness.

A fiber optic sensor for two-dimensional angular displacement measurement is proposed. Linear light receiving fiber arrays arranged as a crisscross spoke are used in the sensor probe. Light intensity received by each fiber will change due to the measured angular displacement and be recorded by the CCD. Based on the Gaussian distribution theory the reflected light spot center can be determined by fitting a Gaussian curve according to received light intensity and position of each fibers. With this method, measurement errors caused by surface reflection index variation, light power fluctuation, and ambient light disturbance can be effectively avoided. The measured angle range is -0.16 rad～0.16 rad. The difference of optical path loss of each receiving fiber reduces the measurement accuracy of this system. The proposed method based on the correction of optical path loss corresponding to each fiber can effectively improve the angular measurement resolution to 3.8×10-4 rad.

To improve dispersion compensation capabilities of chirped long-period fiber grating (LPFG) for fiber communication, the method using thin-clad chirped LPFG is proposed. At first, we analyze how to determine parameters of chirped LPFG according to the transmission signal, such as chirp coefficient and grating length. Then, to compensate dispersion of a signal with bandwidth of 0.2 nm and center wavelength of 1550 nm, the thin-clad chirped LPFG with appropriate parameters is designed. Based on coupled-mode theory and transfer matrix, numerical results show that about 1 m of such thin-clad chirped LPFG can compensate 46 km fiber’s dispersion. Further, the influence of apodizing function, chirp coefficient and cross-coupling coefficient on the dispersion of thin-clad chirped LPFG is also analyzed.

Based on the coupled-mode theory, a simple method to distinguish circular-birefringence fibers is presented. It is indicated that in a linear-birefringence single-mode fiber the coupling coefficient between two orthogonnal linearly polarized modes is a imaginary number, and the coupling coefficient will be real while in a circular-birefringence fiber. From this fact and the symmatry of the refractive index profile of the fiber cross-sections, we conclude that fiber structure is kept unchanged in case of opposite location of fiber axes is one of the three necessary conditions for a circular birefringent fiber. According to this rule, only twisted fibers and helical fibers (drawn in viscous state at a high temperature) are really circular birefringent fibers.

This paper reports an achievement of a novel polarization stabilization system, which can realize the stable states of polarization (SOP) output, especially any output stable SOP you want. The experiments were done for the cases including different varying frequencies and phase amplitudes generated by a polarization scrambler. The stabilizations of SOP can be realized up to 8 kHz for the peak-to-peak π/2 scramble signals. The analysis of time-consuming distribution showed that the polarization controller occupied 71% of the total time, while the stable algorithm and data processing only occupied 8%.

An investigation of all-optical wavelength conversion based on semiconductor optical amplifier (SOA) and delay interferometer (DI) scheme is presented. The working principle of SOA-DI configuration is explained and the functions of DI parameters are analyzed. Experiments of wavelength conversion at 10 Gb/s and 40 Gb/s for return-to-zero format are demonstrated. The experimental results show that wavelength conversion exploiting cross-gain modulation leads to reversed polarity and degradation of extinction ratio (ER) for the converted signal, and the performance of the wavelength conversion at a high bit rate is degraded. In addition, the results show that the wavelength conversion based on SOA-DI scheme can preserve the data polarity and improve the ER of the converted signal so that the performance of wavelength conversion using one single SOA is improved and the system can operate at a high bit rate. The SOA-DI scheme has advantages of compactness and photonic integration potential.

Optical packets assembly algorithm is analyzed when traffic shapes in an optical resilient packet ring (ORPR) network and a new algorithm is proposed for ORPR network by controlling the time in transmission. The algorithm is based on a hybrid threshold assembly algorithm. It adds a parameter to control the interval between optical packets so that the traffic in each time unit is smoothed. It also ensures the quality of service (QoS) performances of the network and fits for the ORPR network with limited optical buffer. The average assembly time-delay of optical packets is analyzed in detail. By adjusting the interval of packet transmission in the new algorithm, we obtain about the same distribution of assembly time-delay under different traffic loads. The stable packets average assembly time-delay is very important to QoS and fairness of ORPR. Choosing the good timing for packet transmission is one of the keys to ensure the QoS and fairness of the ORPR. Simulation results demonstrate that the new algorithm gives a relatively stable packets average assembly time-delay and dispatching is satisfied in most situations in the ORPR network.

The study on the propagation of laser beams of new special modes is a fundamental and significant topic in laser application. Based on the Collins integral formula, the propagation of generalized hypergeometric beams in paraxial ABCD optical systems is studied and the analytical expressions for complex amplitude at output plane are obtained. It is shown that the complex amplitude distribution after propagation in paraxial ABCD optical systems is proportional to Kummer function. By expanding Kummer function as a series, the modulus of this complex amplitude at the output plane could be represented as series summation which shows that the transverse structure of generalized hypergeometric beams propagating in paraxial ABCD optical systems will generally change its form. As a special optical system, the near-field and far-field diffraction behavior in free space is discussed. The transverse structures of both the near-field and far-field are a series of concentric rings and the spatial frequency increases with increase of the radial coordinate. The normalization coefficient was derived and also the relation between simplified modes of hyper-geometric mode and Gaussian modes is analyzed.

A new kernel anisotropic diffusion noise removal algorithm is proposed, through anisotropic diffusion and kernel method, to denoise linear crack on the light rail beam surface, and preferable results are obtained. On the basis of anisotropic diffusion, an enhancement operator which promotes the weak crack edge is added, and according to the characteristics of noise uniformly distributing in the multi-dimensional space, the low-dimensional data is promoted to high-dimensional space. Except for denoising in the kernel space, average absolute difference value of automatic diffusion termination criterion is introduced to enhance the efficiency of diffusion. A different edge enhanced weight is choosed to discuss the appropriate weight range. This method has been applied to noise removal of low signal-to-noise ratio track surface beam linear crack of 0.4 mm width. Compared with median filter and traditional P-M anisotropic diffusion, the kernel anisotropic diffusion outperforms them for denoised result and signal-to-noise ratio.

According to data smooth theory, the best trade-off fractional order of 7.9, which the symmetric fractional B-spline wavelets can achieve between its smoothness and approximation texture, is deduced. A new thresholding formula which has self-adaptability with the order of the fractional spline wavelet, is derived, through improving the wavelet denosing model based on biva-Shrink neighboring coefficients relevance. Fractional spline wavelet transform is a new powerful tool for removing noise and irrelevant information from denoised images. Experimental result testifies the obtained theoretic result. Comparied with traditional denoising algorithms, it can achieve higher subjective and objective image qualities, especially for texture images. When the Barbara image with variance is no more than 10, the peak signal-to-noise ratio of the denoised image can reach 34.9842 and its geometric textures are well-protected after denoising by this algorithm.

With the development of projectors, the display quality has been widely concerned. The luminance uniformity is a common problem in projection display. Most images with high gray value tend to saturate after uniformity correction, while the common clipping method will decrease the uniformity greatly. In order to solve this problem, a photometric model based on projector-camera system was set up, and then a robust nonlinear algorithm for luminance uniformity correction was proposed on the basis of the traditional linear mapping method. The experimental results indicate that the display luminance of the projector is decreased by 50% from center to edge, corresponding to the relative root mean square (RRMS) error of luminance uniformity of 17.7%. After luminance correction, the RRMS value of saturated images decreases to 1.69%, almost as good as that for nonsaturated images (1.55%), while the average luminance level is well preserved in general.

The experiments of high peak pulsed laser-induced damage to fused-silica fibers have been carried out. The experimental results show that all the damage sites accrued on the fiber end-faces. The morphologies of damaged fiber end faces are observed and recorded using metallurgical microscope. Micrographs of fiber end faces are processed using a Matlab program; the distribution characterizations of damaged sites on fiber end faces are obtained. According to the computing results, we find that the damage sites distribution obey certain regularities, which are different between on the input end faces and on the output end faces; The sizes of damaged sites obey normal distribution; The location distribution of damaged sites is strongly related to input or output laser characterization; The morphologies of damaged fiber end faces are strongly related to the mechanism of laser-induce damaged to fiber end faces.

The nonlinear detector response of the infrared focal plane arrays (IRFPA) and its drift characteristics will result in the error of nonuniformity correction(NUC). In view of this fact, an S-curve response model based scene adaptive NUC algorithm is proposed. The algorithm takes logarithm to linearize the output signal of IRFPA, and employs adaptive filtering technique to correct the linear signal. The corresponding exponential transform is used to recover the corrected signal. The performance of the proposed algorithm is tested with artificial blackbody images and real infrared video sequence, respectively. The experimental results validate that the new proposed algorithm can promote the correction precision and expand the dynamic range of detector response considerably.

A MWIR/SWIR polarization imaging optical system is presented, and a novel common-aperture optical system for MWIR/SWIR polarization imager is designed. The MWIR optical system is composed by an all-reflective afocal system, a beamsplitter, a secondary telescope, an infrared polarizer, and an infrared objective. For controlling the apertures of the first mirror, the two face reflective mirror, the beamsplitter and the infrared polarizer, a triple imaging optical system is designed. By the beamsplitter the light is divided into the MWIR (3～5 μm) waveband and the SWIR (1～2.5 μm) waveband, they are converged on two detectors respectively by two objectives, the dual wave-band optical system realized common aperture. The imaging quality is perfect, it can be satisfied to the imager, and the design result is provided.

The maximum detection range equations of the infrared panoramic searching system are investigated, based on the focal plane irradiance distribution, the minimum resolved contrast, detection probability, false alarm probability and the bandwidth. The main factors including the target characteristics, atmosphere background, and the optical, mechanical and electrical characteristics of the systems are analyzed. In the equation of detection range based on the irradiance distribution, the results show that the radiation propagation intensity of target has approximate ascending parabola relation with detection range, atmosphere extinction coefficient has descendent parabola relation with detection range, the system focus has direct proportion with detection range, and the inherent contrast of the target has ascending parabola relation with detection range. Given the definite false alarm probability, the signal noise ratio has approximate descendent parabola relation with detection range, while detector dwell time has approximate direct proportion relation. The system detection distance under the above factors are simulated ,and the results show that the detection range of panoramic visible light searching system can achieve more than 100 km, panoramic infrared searching system can achieve more than 60 km with the target radiation propagation intensity of 70 J/(s·sr), the connatural contrast of more than 4, atmosphere extinction coefficient of less than 0.1 and the system focus of 500 mm.

A high-sensitivity system of continuous wave cavity ringdown spectroscopy (CW-CRDS) is presented, which uses an ultralow-thermal expansion glass-ceramic as the cavity and a Distributed-Feedback (DFB) laser diode as the light source. In the system, the laser frequency overlaps with one of cavity modes via scanning the cavity length. And the input laser is switched off or on by modulating the injection current of laser diode. Furthermore, the laser wavelength is scanned by tuning its operating temperature or injection current. The noise-equivalent detection sensitivity of 7.6×10-9 cm-1 is achieved in 24.9 cm cavity length. With an ultra-high vacuum system, the intensity and doppler broadening line-width of 19 spectral lines of N2O molecule in the range of6586.5～6596.5 cm-1 are measured, and then the difference between measurement results and that of Hitran2004 database is discussed.

Three-dimensional measurement of structured light of color grating can complete phase match of pixel between single image in left and right cameras. It can realize the reconstruction of surface of objects that move or deform, but the measurement accuracy needs to be improved. Based on the coarse match by phase, more accurate match can be achieved in local region by digital correlation technique of stereo vision between left and right images. As calculating the correlation coefficient, the weights in different color channels are self-adapted according to the color variety feature in different period of color grating and the dimension of correlation windows in left or right is self-adapted according to surface distortion feature from different view. The sub-pixel matching is achieved by bilinear interpolation along the direction of epipolar line. The experimental results prove that the matching technique of self-adaptation digital correlation can improve the accuracy of measurement effectively, and expand the range of application while maintaining the advantages of dynamic measurement and high resolution.

A new method of measuring guide straightness error is proposed. Based on a linear relationship between polarizing angle and lateral offset position displacement. A peculiar polarized beam, whose polarization angles are distributed linearly as lateral direction coordinates, is modulated by a designed active optical modulator based on polarization interference principle. The polarizing angles of the beam are detected by an optical detecting component and an optical slit, which move correspondingly with the existed guide straightness error. Laboratory experiments are conducted to validate the method and the results show that the correlation coefficients of the linear fitting curves between the polarizing angle and offset displacement is above 0.9995, with the standard deviation of the repeatability test within 1 μm. The range of straightness error measurement is above 0.5 mm with the resolution level at submicron grade. This method minimizes the effects caused by the variation of light intensity and guide surface error and possesses the advantages of convenience, high reliability and accuracy. After modification, it can measure two-dimensional straightuess error with the same precision as the autocollimator. It can be applied to actual industrial applications.

Lock-in is important to rate-biased laser gyro, but accurate lock-in measurement is always difficult. According to lock-in equation of laser gyro, approximate relation of lock-in and laser gyro output signal harmonic is derived from theoretical approximation, and based on this approximate relation the harmonic measurement for laser gyro lock-in is provided. Modification and errors analysis are processed through accurate numerical result of lock-in equation. Finally lock-in value of a laser gyro is measured by harmonic method, and the result shows that the measurement accuracy can be better than 5%.

A new method to measure the three dimensional (3D) shape of the aspheric mirror is proposed. In the measurement, a liquid crystal display(LCD)screen displays the sine fringe pattern and a camera captures the deformed fringe pattern generated by the reflection of the mirror. And the screen and the camera are translated along the measured mirror axis, respectively. At each movement, the camera records the fringe patterns from the screen located at two different positions. By phase shifting technique, the phase information in the deformed fringe pattern can be gotten. Every camera pixel corresponds to a point on the tested mirror and its coordinate and slope can be determined. By integral processing, the 3D shape of the measured mirror can be reconstructed. This method doesn’t need interferometer and assistant mirror. So it can reconstruct the tested mirror flexibly and cheaply. Moreover, this method owns strong ability of anti-noise. With large noise, this method also can reconstruct the 3D shape of aspheric mirror. Computer simulations and preliminary experiment validate the feasibility of this method.

A new micro wedge-ring poor pixels infrared detector is presented, and its special detecting principles are expatiated. The simulated wedge-ring poor pixels images are formed by merging picture elements. Further, with the help of log-polar transformation, it can be easily found that there is much information in the center and little on the edge. Based on grey histogram, targets are detected by using an adaptive real-time threshold segmentation algorithm, and are tracked by adopting a tracking algorithm. In the tracking algorithm the possible states of target were partitioned, and the target position and velocity were estimated on the basis of sequence images. Utilizing the basic geometric figures the wedge-ring poor pixels images are tested. For the different shape basic figures with different orientations, their externalities are mostly different. Even though some have similarities, they can be distinguished by the proportion of pixels’ grey values. The results show that the possible application of poor pixels detector in the target detection and recognition system and it is very significant to continue corresponding research.

A model was established to analyze the side bands suppression methods of mode-locked fiber laser. The model was based on nonlinear Schrdinger (NLS) equation, nonlinear polarization rotation mode-locking principle and dispersion wave interference theory. The affects of cavity length, gain fiber length and coupling output ratio on the side bands were anelyzed. Mode-locked fiber laser with 0.5 m, 1.5 m and 3 m Er3+-doped fiber (EDF), 13 m, 16 m and 26 m ring length and different output ratios was experimentally studied. Theoretical simulation and experiments show that the EDF length should be appropriately increased to restrain side bands, the ring length should be decreased, the output coupling ratio should be small and the fiber laser should be mode-locked on the fundamental order. The fiber laser with 3 m EDF, 10% ratio and 13 m ring length was experimentally carried out. The output pulse with restrained side bands and spectrum width of 20.4 nm is detected. The repetition rate is 15.87 MHz, and the single pulse energy is 0.52 nJ. The fluctuations of pulse amplitude and spectrum width are 4% and 2%.

A new method for side pumping of double-clad fiber lasers through reflection of micro-prism is described, which can pump the light sources from LDs, especially LD arrays, into double-clad fibers easily and effectively. Advantages of this technique include no destruction of inner-cladding, high pumping efficiency, simplicity, low cost, easy industrialization and so on. The mechanism and the application method are introduced and the theoretical coupling efficiency is given (up to 90%). Then primary experiment is made to verify the method and 50% coupling efficiency is gotten. The parameters of the prism and the applied areas is analged.

The fast ignitor scheme in inertial confined fusion requires ultrashort laser pulse with high signal-to-noise ratio (SNR). The amplified spontaneous emission (ASE) noise modulations in pump pulse are transferred onto the signal spectrum and these modulations of signal spectrum generate the time-pedestal before and after this main pulse, which degrades the signal-to-noise ratio. The restrictions of the SNR by the random ASE noise and the duration of its pedestal are numerically modeled. A number of ways that can reduce the noise level and increase the signal-to-noise ratio are discussed.

To study the precise line profile in the mid-infrared (MIR) region, a versatile continuous wave (CW) MIR difference frequency generation (DFG) spectrometer is built up utilizing a CW Ti:Sapphire laser (700～900 nm) and a CW single-frequency 1064 nm Nd:YAG laser. The spectrometer covers the 2.5～5 μm region by tuning the frequency of the Ti:Sapphire laser. The frequency of the Nd:YAG laser is stabilized within 1×10-5 cm-1 when it is locked on the Doppler-broadened I2 absorption line near 532nm. As a result, the DFG laser frequency is stabilized to the level of 1×10-4 cm-1, which is suitable for precise line profile measurements. An absorption line of CH4 near 2927 cm-1 was recorded using this spectrometer and it presents an example for the sensitive detection with the frequency-modulation spectroscopy method.

We study nonlinear physical characteristic of a semiconductor laser due to external optical injection. By small-signal analysis, we analyze dynamically behavior of the laser. Effect of the external light injection on nonlinear frequency chirping is analyzed and static maximal locking formula is given. We indicate theoretically that the frequency chirping of the optical injection laser is nonlinear related to the external injected light and the physical state of the laser while this nonlinear effect is promoted with adding the optical injection index. And the nonlinear frequency chirping can be nonlinearly affected by the frequency detuning and the linewidth broadening factor. Obviously, the nonlinear frequency chirping is physically different from the frequency chirping of the absolute laser. The frequency detuning, the maximal locking region, the bifurcation condition and bifurcation period formula are introduced. Dynamical behavior from bifurcation to chaos is numerically simulated with the external optical frequency detuning and the injection parameter, in detail. A single period, a tri-period, a multi-period, chaos, fully developed chaos and their rotating whirl attractors, frequencies, spectrums and waveforms are analyzed numerically, respectively. The maximum Lyapunov exponent, static maximal locking region and bifurcation period are calculated numerically, respectively. Bifurcation of the laser with the frequency detuning is numerically simulated. Unstable dynamical behavior and spectrum characteristic of the laser system is comprehended gradually.

Stereo matching is a long active topic and difficult problem in computer vision, and is a crucial technique in stereovision. An algorithm by combining initial matching via segmentation-based variable support with greedy disparity estimation as post-processing is proposed to resolve the ambiguity of binocular stereo problem in a local perspective. Firstly, color segmentation is conducted on both stereo images, and segmentation-based adaptive support weight is assigned for each pixel to eliminate ambiguity in feature matching, and then matching cost with the variable support is calculated to obtain initial disparity. Secondly, to address more other complex ambiguity in low textured and repetitive patterns or large occluded regions etc., greedy disparity estimation procedure consists sequentially of three steps: segmentation-based disparity calibration, narrow occlusion handling and multi-directional weighted least square fitting. The experimental results indicate that this technique with segmentation cues can increase robustness against outliers and obtain accurate and dense disparity effectively. It’s concise and efficient.

Range data registration is a key issue of 3D optical measurement. The method based on markers has the advantage of cheapness, convenience and fastness. But the problem of error accumulation is still unsolved for multiple viewing fields. A fine registration method to register the multiple range data with non-coding markers is proposed. Image process and pattern recognition techniques are employed to detect the sub-pixel location of markers. The markers’ local coordinates in 3D space are computed from optical measurement system. Through the principle of rigid invariance of distance in 3D Euclidean space, the fine registration of two range data is completed. Moreover, a global iterative algorithm is proposed for accurate registration of multiple range data. Using this algorithm, the maximum error reduces from 0.123 mm to 0.076 mm. The experimental results illustrate the validity of this method. It can automatically fast register multiple range data and decrease error accumulation.

A crop row detection method based on machine vision was put forward to detect crop rows from farmland features images fast and effectively. In the process of image pre-processing, a new algorithm of the central line detection was proposed instead of the traditional vertical projection, and then a novel line detection method based on randomized algorithm was presented. Firstly, two different points are selected randomly from data space composed of locating points which determine a candidate line. Secondly, under the given distance tolerance, a strip region along the line direction is got, and the number of locating points in the region was accumulated. Lastly, the threshold rules are applied to determining whether the candidate line is the desired one. Test results show that the method can accurately find the crop rows under different light conditions and different growth stages. The image processing time is about 120 ms. Compared with Hough Transform (HT) and Randomized Hough Transform (RHT), the proposed algorithm has the advantages of smaller size of computer memory, shorter computational time and good robustness.

The 3D reconstruction based on binocular stereo vision is a main part of the machine vision technology and has a variety of applications in robot navigation, aerial surveying and mapping, medical imaging, industrial inspection, etc.. With analysis of the relation between 3D coordinates of the mesh candidates and 2D coordinates in images, the mesh candidates similarity of gray value based stereo vision method was improved. Multi-resolution mesh grid was established corresponding to the wavelet decomposed images. The depth information of the object was reconstructed according to the similarity of the gray values between both images with the choosing strategy from the rough to the fine. The algorithm has obvious superiorities in computation and accuracy shown by experiments using Matlab.

The electronic structure and optical properties of ZnO are calculated in different Al doping. The effects of Al doping on the crystal structure, band structure, density of state and optical properties are analysed by using the first-principles calculation of plane wave ultra-soft pseudo-potential technology based on density function theory(DFT). The calculated results reveal that there are lots of carriers in the bottom of conduction bands due to the donor doping, which improve greatly the conductivity of the Al-doped system, and the Fermi level moves into conduction bands(CBs). Moreover, the optical band gap is broadened and moves towards lower energy. The optical transmittance of Al doped AZO is as high as 85% in the visible region, the UV absorption edge is blue shifted greatly with increasing Al doping concentration. All calculated results showe that the AZO materials can be used as excellent transparent conducting films.

The method of B3LYP/6-311G(d) in density functional theory(DET)was used to optimize the geometric configuration and study the photoelectron energy spectrum of Ga2Asn (n=1-5) ion clusters. The ground-state structure of the clusters has been obtained, the stability of which shows a certain degree of even/odd alternation with the increase of the total atoms number. The structure with odd number of total atoms is more stable than those with even number of total atoms in Ga2As-n clusters, while it is quite the contrary in Ga2As+n clusters. The energy gap between the highest-occupied molecular orbital (HOMO) and the lowest-unoccupied molecular orbital (LUMO) displays a certain degree of even/odd alternation, with the increase of the arsenic atoms number. The energy gap values with even number of arsenic atoms are basically the same, but they are rather different with odd number of arsenic atoms.

The epsilon’s nonlinearity of permittivity and its effects upon the characteristics of a two-dimensional composite created by arrays of wires and split-ring resonators embedded into a nonlinear dielectric were reported. The dependences of the real part and imaginary part of the effective permittivity of the structure on the varying external magnetic field strength were calculated. It is demonstrated that the real part of the effective permittivity has hysteresis structures. This property of permittivity results in the switching of the composite among right-handed materials, left-handed materials, epsilon-negative materials, and mu-negative materials under different conditions, which can be controlled by a proper choice of the external magnetic-field strength (intensity of incident electromagnetic waves) in a certain frequency range. This phenomenon can be used to realize the micro-wave or optical switching devices.

A new kind of photonic crystal cross waveguides with defect structure is propesed. The transmission characteristics are simulated by finite difference time domain method (FDTD). The obtained results show that the spectrum line-width of transmitted light through the photonic crystal waveguide containing defect structure is much narrower than that in the prototype waveguide without defect structure. This waveguide possesses narrow band filtering function. When the defect medium refractive index is increased, the center frequency of the transmitted spectrum decreases linearly. When the diameter of defect medium center pillar in increased, the center frequency of the transmitted spectrum is reduced. It is expected that this type of defect photonic crystal wave guides may serve as new narrow band filter,light splitter and tunable frequency selector.

Through multi-beam coherent surface plasmon polaritons (SPPs) excited by p-polarized light beams, and optimizing exposal parameter of interference lithography, high resolution and contrast periodicity nanometer structure is obtained by using the features of short wavelength and near-field enhanced effect. The principle for nanometer photon-crystal fabrication by the method of multi-beam coherent SPPs intervening is expatiatedon. The relation between the magnetic-field distribution and the light beam number is conducted. The interference field tends complicated with the rise of beam numbers, and the simulation results are given. The intensity distributions of tri-beam SPPs interference and exposure with six-beam SPPs interference are simulated, and the results of interferential exposure about modulation technology are analyzed. The method is suitable for fabricating nanometer photonic crystal and deep sub-micrometer periodic patterns in large field size used in opto-eletronical components, and it can reduce cost effectively.

A kind of one-dimensional doped photonic crystal with fractal characteristic is constructed and investigated. Numerical results show that such a structure can produce multiple transmission channels, and each channel can be tuned independently. By changing the number of the defects inside the coupling layers, the number of the narrow-band transmission peaks inside the channel can be tuned. As the frequency of a transmission channel changes, all transmission peaks in the channel will also shift, while the frequency interval of these peaks remains nearly invariant. These fractal structures are useful for the design of multichannel filters.

A new Michelson interferometer sensor is proposed based on the self-collimation effect of two-dimensional air-cylinder photonic crystal. By introducing a sensor area and changing its refractive index, a phase shift is created and thus lead to the change of optical output power. Self-collimation frequency range can be determined by the equal frequency contours calculated with the plane wave expansion method. Two-dimensional finite-difference time-domain technique is also used, 120 nm/RIU sensitivity is achieved. The simulated performance is realized by the incidence of single frequency light. The proposed photonic crystal sensor is defect-free configuration and thus reduces the fabrication difficulty. For 1.55 μm central operating wavelength, the dimensions of such sensors are only tens of microns. It is desirable to perform ultra-parallel sensor by cascading beam splitters.

A novel wavelength-division demultiplexer which is based on photonic crystal fibers (PCFs) with hybrid light-guiding mechanism has been proposed. Different from the traditional PCFs, hybrid light-guiding PCFs share the properties of both the index-guiding PCFs and the bandgap-guiding PCFs. The proposed wavelength-division demultiplexer can be used in the coarse wavelength-division multiplexing system. The proposed wavelength-division demultiplexer consists of three cores. High-index materials are filled into the circle of air holes around the three cores. Because the material’s indices are different, the PCF operates by a hybrid light-guiding mechanism. According to the coupled-mode theory, the coupling happens when the propagation constants of two adjacent cores are equal at a particular wavelength λ0. There are two corresponding wavelengths, so two beams of light with different wavelengths can put out in different cores if choosing the appropriate parameters of PCFs. By full-vectorial finite element method (FEM), the properties of PCF are be analyzed and the coupling lengths for different-wavelength lights were calculated. Numerical simulations by beam propagation method demonstrate that it is possible to obtain a 4.3 mm-long wavelength-division demultiplexer which can separate two lights with wavelength 1.31 μm and 1.55 μm, respectively.

Photonic crystals are man-made crystals consisting of two or more kinds of different dielectric materials arrayed periodically. Because of the collective modulation of the periodic dielectric distribution to the incident electromagnetic waves, the directions of the group velocity and the phase velocity can be opposite, a photonic crystal slab can work as a negative refractive-index material. In the letter we study the influence of the dielectric shape on the negative refraction and near-field imaging of the photonic crystal slab. By the analysis of near-field imaging properties of the two-dimensional square-lattice photonic crystals consisting of circular, square, triangular, elliptical and rectangular rods, respectively, we find that the image spot moves laterally with respective to the rectangular slab when the symmetry of the rods reduces for a certain degree. With the systemic analysis of the equifrequency-surface contours, we find that an excellent-quality near-field image of the photonic crystal slab can be formed mainly by the self-collimation and the negative-refraction effects.

The single-cell-molecular technique based on optical tweezers and Raman spectroscopy is employed to study single reticulocytes and small lymphocytes of Sprague Dawley (S.D.) rat in nearly physiological solution. The spectra of single reticulocytes and small lymphocytes are obviously different due to their components. The main differences show that characteristic Raman bands of the protein are 1212, 1548, 1607 and 1616 cm-1 for reticulocytes, 1001 and 1661 cm-1 for small lymphocytes, and that of nucleic acid is 1584 cm-1 for both of them. The content of nucleic acid of small lymphocytes is more than that of reticulocytes, but for protein it is reverse by the histogram analysis of part characteristic Raman bands. Furthermore, the reticulocytes and small lymphocytes can be distinguished completely by principal component analysis and discriminant function analysis. The way of distinguishing quickly and accurately of single reticulocytes and small lymphocytes by the Raman spectra cannot be realized by optical microscope. It also provides a new method to distinguish two kinds of cells in blood for modern biomedicine study.

Dynamic structural changes of bio-macromolecules undergoing biochemical reactions can be studied using the single-pair fluorescence resonance energy transfer (sp-FRET) experiments, which can be used as a nanoscale ruler. The ability to use the optical microcavity to amplify the sp-FRET fluorescence signal has been investigated. When the single FRET-coupled pair and the attached bio-macromolecule are placed in an optical cavity with the emission mode of the acceptor dye in resonance with the cavity mode, the results of a fully quantum-mechanical treatment show that, the photon emission intensity from acceptor amplified by the cavity coupling field mode would reach a significant value, leading to a much brighter photon signal. It is concluded that the microcavity can serve as a sharper structural-sensitivity observable tool to the distance of single pair. The work establishes experimental methods and useful guidelines for the single-molecule studies of biomacromolecules in real time at molecule scale.

Spontaneous photon emission was produced by the transition of the living biological system from upper-state to low-lying state. According to Frhlich’s theory, living biosystem is an extreme coherence’s open system. The motion state possesses a collective vibration effect and the biosystem can be regarded as a set of vibrators with same character. The transmit equation of biophoton in biosystem was deduced. This is a typical Sine-Gordon equation. It showed biophoton has soliton character in the living biological system. In conclusion, biophoton can be an ideal carrier of biosystem information. Furthermore, the interaction of weak laser photon with biomolecule system is discussed in this work. It shows that weak laser irradiation can excite the biologic vibrator from excited state to lower energy state with relaxation phenomenon and photon emission.

The infection of the room temperature to the differential laser gyro’s null shift is very complex. In order to finding out the infection mechanism, surface temperature, gyro’s null shift, laser intensity difference and sum between the two signals, current difference between the two arms discharge and the sum frequency are tested at the same time. Through analyzing and calculating the correlation coefficient between temperature and other, parameters, it is found that the correlation between the gyro’s parameters and surface temperature is different along with testing time. It’s also different between different experiments, so the effect of temperature compensation is limited. The sum frequency is proportional linearly to the temperature, but the linearly proportional coefficient is different along with testing time and different experiments.

A micro-lens optical fiber Fabry-Pérot interferometer is demonstrated by manufacturing micro-lenses on the mirrored endfaces of two single-mode optical fibers. The mode field of the Fabry-Pérot cavity is theoretically calculated by using ABCD matrix method. The mode field of the Fabry-Pérot cavity matches that of a single-mode optical fiber very well due to the focusing of micro-lenses, thus resulting in high finesse and low insertion loss. A micro-lens optical fiber Fabry-Pérot interferometer with free spectral range of 32.28 nm, finesse of 78 and peak transmittance of 73% is experimentally demonstrated. It can maintain a peak transmittance better than 50%, even if the optical cavity length of the Fabry-Pérot cavity is increased to 100 μm. This kind of micro-lens optical fiber Fabry-Pérot interferometer is easy to build, and can be used as optical fiber Fabry-Pérot filters and high-finesse optical fiber Fabry-Pérot sensors.

Optical and electrical characterization of high-power green LED on Si (111) substrate fabricated by MOCVD with chip dimension of 400 μm×600 μm is studued. The forward bias of the LED with Ag reflector is about 3.59 V under 20 mA, and the light output power is about 7.3 mW with dominant wavelength of 518 nm. The light output power achieves 28.2 mW under 90 mA, the light output efficiency is 7.5%, and the saturated output current is 600 mA. The light degradation of LED with Ag reflector is smaller than that without Ag reflector after 216 h accelerated aging test under 200 mA. This phenomenon is induced by Ag reflector, which can raise the light extraction efficiency and lower the temperature of the chip itself. This characterization of great light efficiency, light degradation and saturated output current suggests that GaN-based green LED on Si substrate has a promising prospect.

The squeezing properties of the single-mode squeezing coherent light interacting with a three-level Ξ-scheme atomic Bose-Einstein condensate (BEC) are studied by means of quantum theory. The results show that the fluctuation of the light field can be squeezed periodically. The initial occupancy of the BEC atomic levels has great influence on the squeezing properties of light and the period of oscillation of the squeezing is relating to the circle frequency of the light. If all the BEC atoms are in the ground state at the initial moment, the squeezing of light appears regular periodicity. However, if some of the atoms are in the excited states at the initial moment, the distortion of the squeezing periodicity of light will emerges obviously, and this distortion is growing with the increase of the excited state’s occupancy. The occupancy of the excited states also influences the squeezing depth of light. The greater the occupancy of the excited states is, the deeper the squeezing.

Using the Wigner operator in coherent state representation and the technique of integration within an ordered product of operators (IWOP), the Wigner function of the thermal coherent state was obtained. By adopting the coherent state representation and normal product form of operators, the Wigner function of the corresponding mixed states was obtained too. It is found that the Wigner function of the thermal coherent state agrees with that of the corresponding mixed states, which support the thermofield dynamics laws. And it is convenient to study the Wigner functions of quantum states by the coherent state representation, IWOP technique and normal product form of operators. The results provide further new insights into the phase space technology of quantum statistics and thermo field dynamics, and have certain theoretical guidance meaning for studying other quantum phase-space distribution functions.

The influences of the temperature on the effective mass of the exciton, for which the electron (hole) is strongly coupled with interface-optical phonons but weakly coupled with bulk-longitudinal-optical phonons in a quantum well, are studied by means of Tokuda’s improved linear combination operator and a modified Lee-Low-Pines transformation method. The resuls indicate that the effective mass (M*ex－LO) of the exciton, which is induced by the electron (hole) weakly coupled with bulk-longitudinal-optical phonons, will increase with the well width (N) increasing and first increase and then decrease, finally tends to a stable value with the distance between the electron and the hole (ρ) increasing. The influence of temperature on M*ex－LO and its changing with N and ρ is obvious. The change of M*ex－LO with T is strongly related to the quantum-size effect. The effective mass M*ex－IO of the exciton, which is induced by the electron (hole) strongly coupled with interface-optical phonons, will decrease with increasing N, increase with increasing T and first increase and then decrease, finally tends to a stable value with increasing ρ.But the influence of temperature on M*ex－IO and its changing with N and ρ is not obvious.

Focusing on the research of the UV coverage situation on the OAS telescope, this paper introduces the concept of UV coverage technology in the OAS imaging technology and the two statements of real-time UV coverage and none real-time UV coverage. It also researches the UV coverage approach with four small telescopes to compose an OAS telescope. It takes an actual observed object as an example to increase the optimization to the UV coverage method. Meanwhile, it also raises the method of revolving aperture to increase and optimize the UV coverage and proposes the project of the optimization for sub-aperture arrangement of the OAS telescope. The result of the UV coverage optimization is also acquired, and a living example is given, which is the simulation of an OAS telescope with UV coverage technology and sub-aperture arrangement optimization.

A new method for recognition of raw material cultivar of manufactured tea with Fisher discriminant classification using near infrared spectra. In this study, spectra of samples with different raw material cultivar(Longjing43# and other cultivar) were collected. 20 principal components were obtained by PCA. 8 Principal components by step wise was used to establish the Fisher function for discriminant classification to recognize the raw material cultivar of manufactured tea. The result showed that the function performed well in recognition of raw material cultivar of manufactured tea. The accuracy for recognition was 96.8% in calibration set. 93.5% was obtained for unknown samples in test set. The result proved that it was feasible to recognize the raw material cultivar with combined analysis of PCA and Fisher discriminant classification using near infrared spectra.

In order to study the biochemical abnormality of metabolites from tissues or cells at the molecular level, the surface enhanced Raman scattering technique was used to detect the serums from diabetes mellitus and complication (coronary disease, glaucoma and cerebral infarction). It is found that the characteristics surface-enhanced raman spectra (SERS) of serums are very similar to that from diabetes mellitus, which indicates that the changes of molecular structure or content from the metabolites of tissues or cells in these diseases are similar. The significant differences of SERS are found between normal and diseased serums. Especially, the relative intensity of the band from patients increases obviously at 725 cm-1.The partial reinforcement comes form the adenines’ contribution and is independent of the blood sugar level, which indicates that there exist many adenines in these serums. The results will offer the experimental basis for the biochemical study and clinical diagnosis of diabetes mellitus and complication.

Laser-induced breakdown spectroscopy was used to analyze coal samples, and the influence of sample morphology on laser ablation properties of coal was analyzed. Coal samples with different morphologies were ablated by 532 nm pulse laser, and plasma was formed at atmospheric pressure. The multi-channel fiber spectroscopy and CCD detector were used to collect and detect of plasma emission signal. The change laws of plasma temperature, electron density and spectral-line intensity with laser energy for different coal samples were analyzed. The analysis results show that sample morphology is a significant influencing factor for laser ablation properties of coal samples. The change laws of plasma temperature, electron density and spectral-line intensity of different samples are obviously different. In the same experimental conditions, the plasma temperature and electron density of pulverized coal are higher than those of lump coal, but the spectral-lines intensity of lump coal is higher than that of pulverized coal.

The propagation properties of ultrashort laser pulses in water is investigated with the extended nonlinear Schrdinger equation and the electron density equation. With the theoretical model that incorporates the diffraction, normal group-velocity dispersion, multiphoton absorption, self-focusing and self-defocusing effects generated by the laser-induced eletron plasma, the spatio-temporal distribution of the on-axis laser power density and plasma density during the propagation are obtained by fininte difference method. Simulation of the underlying propagation dynamics of the ultrashort laser in water reveals that the competitive relationship between nonlinear self-focusing and self-defocusing during the pulse propagation. Moreover, the influence of laser energy, pulse duration and focusing geometry on the structure of plasma filament and the reshaping of energy fluence are discussed. The results may be benefical to understand and push forward the application of the ultrashort laser pulses in medicine, laser safety and processing in water.