Compared with conventional stack actuator deformable mirrors, the bimorph deformable mirrors have more simple structures, larger stroke, lower cost and less time consumption. Therefore, they are potential substitutes of stack actuator deformable mirrors in adaptive optics systems. A prototype of 20-element bimorph deformable mirror is designed and fabricated in order to verify the process and investigate its basic characters. This prototype has two PZT layers, the outer one is divided into 19 electrodes, and the inner one has a whole defocus electrode. The influence functions of the fabricated prototype are measured by using a Veeco interferometer and the correction ability for the first 36 Zernike aberrations is simulated. The results show that it has a good fitting ability for low order Zernike aberrations, especially for defocus, and it achieves an amplitude more than 8 μm. And this ability decreases as the increase of space frequency, which indicates that this bimorph deformable mirror is very suitable for correcting low order aberrations. In addition, fitting abilities of the fabricated prototype for correcting Zernike aberrations with different clear apertures are discussed.

In order to obtain the near-field phase distribution by using the far field intensity information, a multi-frame algorithm is proposed. It is a phase-retrieval algorithm which carries out the original Gerchberg-Saxton (G-S) algorithm by using more than one far field, and the new far fields are generated by adding prescient aberrations to the unknown phase. A novel method to achieve the multi-frame G-S algorithm by using the deformable mirror (DM) is proposed, and its feasibility is certified by numerical simulations and experiments. The simulated results further imply that the multi-frame G-S algorithm is capable of recovering the atomspheric aberrations within 50 iteration loops, on condition that 4 DM surfaces are utilized to build the new far fields, and the root mean square average of residual errors between recovered phases and true phases is less than 0.005 λ, with λ as the light wavelength.

CS2 has a great effect on human health and atmospheric circulation. The new research recently indicates that CS2 in the urban air may primarily come from combustion of coal. A new method for remote sensing of emission from point source was proposed, based on passive differential optical absorption spectroscopy (DOAS), by taking the sun's radiation as light source. The principle and system of passive DOAS were introduced, and the method of spectrum analysis for CS2, including choosing “zero” reference spectrum and reducing the Ring effect for the spectra evaluation was discussed. CS2 in power plants’ emission plume is measured and the column density of CS2 is successfully retrieved. It indicates that burning of coal produces certain CS2 and provides useful evidence for research of main source of CS2.

A long open-path tunable diode laser absorption spectroscopy (TDLAS) system based on wavelength modulation and second harmonic detection is developed. The method of normalized light intensity is adopted to eliminate the influences on the measurement by light intensity, and the measurement error is less than 2%. Then by using this system ambient methane is monitored at Dongpu island of Hefei with 750 m-optical-path. The measurement result is analyzed and the diurnal variation of atmospheric CH4 concentration has a very clear cycle in the Dongpu island. The general characteristics of diurnal variation are the lowest value in the daytime and the highest value at night, with the average concentration range of (1.8～3.4)×10-6, the highest concentration of (3.0～3.4)×10-6, and the lowest concentration of (1.8～2.2)×10-6. Experimental analysis shows that the system can achieve large region on-line monitoring of methane concentration with the distance of about 1～2 km and supply effective method to the monitoring of area emission flux of ecosystem and feasible ground calibration means to the satellite remote sensing.

Approximate nonlinear equation about modes is derived by W. K. B. method for waveguide with perfectly matched layer (PML). Asymptotic solutions for the leaky modes and Berenger modes are derived and the effect of PML is analyzed. Theoretical analysis shows that for leaky modes of transverse electric (TE) case, asymptotic solutions of waveguide are the same as that of open waveguide, but for transverse magnetic (TM) case, asymptotic solutions of waveguide are different from that of open waveguide. For both TE and TM cases of three-layer slab waveguide, if refractive index of top cladding is different form that of bottom cladding, there will be two traces of Berenger modes, otherwise there is only one trace of Berenger modes. Numerical simulations show that these asymptotic solutions of leaky modes and Berenger modes are very close to exact solutions and as the norms of modes become larger, the error will become smaller.

The transmission window of reflection spectrum for phase-shift grating products is not tunable. To solve this problem, a device with Bragg grating-assisted single-mode fiber resonator is proposed. Using the signal flow graph method, the mechanism of the device is analyzed in detail. Meanwhile, analytical expressions of reflectivity and its finesse, full width at half maximum (FWHM) are derived. Matlab computation results show that reflection spectrum of the proposed device is similar to that of phase-shift grating. Location and depth of transmission window are tunable in its reflection spectrum. Influences on its finesse and FWHM by the parameters of the fiber resonator are also discussed, which provides the theoretical basis for improving its performance as frequency selection element for a narrow line width of single-frequency fiber laser.

G.657 fibers are regarded as the first choice for local net and access net such as Fiber to the home (FTTH) systems for their excellent property of bend-insensitive loss. Therefore, this kind of fiber is highly discussed in recent years. A method of fully synthetic process was introduced to fabricate G.657 fibers, and the relation between attributes of fiber and the size of core a and cladding b difference of refractive index of core (Δ1) and cladding (Δ2) were discussed in detail. As a result, when a is between 3.5～4.0 μm, b is between 0.5～1.9 μm, Δ1 between 0.0034～0.0045 and Δ2 between -0.0006～0 fibers complying with the standard of ITU.T G.657.A are obtained, while a is between 2.8～3.2.0 μm, b is between 0.8～2.1 μm, Δ1 between 0.0058～0.0072 and Δ2 between -0.0016～-0.0008 fibers complying with the standard of ITU.T G.657.B are obtained. Structures of the fibers are simple without special dips, grooves or holes, and therefore easy to fabricate, spread and use.

Based on the nonlinear Schrdinger equation, the variational method is used to derive the evolution equations for the parameters of the super-Gaussian pulse in fibers with slowly decreasing dispersion. The effect of initial chirp on the super-Gaussian pulse is discussed. Then three restricted relations between amplitude and width, frequency and chirp, width and chirp are derived. Analytical solution about the evolution of pulse width versus propagation distance is obtained. By using Runge-Kutta algorithm, the influence of the initial chirps and the degree of the pulse’s edge sharpness on the pulse width is described. The results show that initial chirps, dispersion decreasing and the degree of the pulse’s edge sharpness have direct influence on amplitude, width, chirp and phase. The degree of the pulse’s edge sharpness has no effect on pulse central position, and the super-Gaussian pulse in the process of transmission can cause chirps, but the equivalent frequency keeps constant.

The refractive coefficient and extinction coefficient of ferrofluids, and the reflectivity on the fiber-optic end face in ferrofluids versus external magnetic field intensity at different volume concentrations and temperatures were theoretically analyzed and numerically simulated. The results show that volume concentration and magnetic field intensity have a great impact on refractive coefficients and extinction coefficionts of ferrofluids. The sensing heads based on the reflection on the fiber-optic end face in ferrofluids were fabricated, and the optical measurement system was designed, so the relationship between reflectivity and magnetic field intensity was obtained. The experimental results agree with the theoretical analysis. By theory and experiment, the effect of extinction coefficient of ferrofluids on the reflectivity on the fiber-optic end face can not be neglected.

Based on the time-harmonic electromagnetic field and waveguide theory, the analytical expressions for the field components of the spherical transverse-magnetic (TM) and transverse-electric (TE) modes inside a metallic hollow conical waveguide with a sub-wavelength-sized exit hole have been derived. The time-averaged electromagnetic field energy density distribution associated with light transmission and the transmission properties of the spherical TM and TE modal fields inside a sub-wavelength hollow conical waveguide have been studied in detail. Moreover, by using the accurate eigenvalues obtained numerically, the influence of the light wavelength, the taper angle, the aperture diameter as well as the length of the conical waveguide on the time-averaged energy density distribution inside the sub-wavelength metallic hollow conical waveguide has been discussed. The results show that the time-averaged energy density distribution inside the conical waveguide varies quasi-periodically. The quasi-period has relation with the mode, the light wavelength as well as the taper angle. Furthermore, there is a clearly pronounced maximum in the radial dependence. The position of an appreciable maximum for the time-averaged energy density varies rapidly with the light wavelength and the taper angle.

Contourlet transform in image restoration is apt to bring pseudo-Gibbs phenomenon. Nonsubsampled Contourlet (NSCT) has better frequency selectivity and regularity compared with the contourlet transform, and it can overcome pseudo-Gibbs phenomenon. However, learning-based super-resolution need establish the relation of different resolutions. Different from Laplacian pyramid, result of NSCT at each layer is with the same size, but cannot establish multi-resolution pyramid, and it needs large amount of computation. According to the problem of NSCT in learning-based super-resolution, a face image super-resolution restoration algorithm based on INSCT is proposed. In order to represent face images features, the INSCT pyramid is established. For particularity of the face images, corresponding points in matching process are used. Experimental results show that this method has good performance, and achieves better results on subjective visual effects and on objective peak signal-to-noise ratio. And the results are closer to the real images.

Using wavelet fusion and C-means clustering of false color fusion image, a color night-vision method for color transfer algorithm of image is presented. Firstly, before transferring color to the night vision image, the fusion of visible image and infrared image based on wavelet transformation leads to the gray fused image as target image, which keeps texture information and target information well. Secondly, the source color image using color threshold segmentation based on joint relative entropy is segmented. Finally, a C-means clustering algorithm based on the false color fused image is proposed , according to the characteristics of the gray fused image. In this algorithm, the color information of the false color fused image is used for the night vision image clustering as feature data vectors, and the segmentation result is good. Then, transferring color to the night vision image based on the clustering results is carried out and natural colour night vision image is obtained. The automatic color transfer of the night vision images is realized. The color appearance of the obtained image is natural and its texture is also clear. These results indicate that the proposed method will benefit the target identification for human eyes.

A three-dimensional volumetric display system was built based on two-dimensional LED array. Scan mapping method was used for data voxelizaion. Gray scale deviation was caused due to voxelization. Geometric approximation method for calculating gray scale deviation was introduced. Two groups of cube models were built and their mean gray scale deviations and root-mean-square deviations were calculated. The calculated results show that gray scale deviation affects display results more in those images that have more gray details. Display distortions may be caused in images that have plenty of gray details. Gray scale deviation could be corrected partly by improving the hardware of the system and by optimizing the voxelization algorithm. Simulating figures before and after gray scale deviation correction show that there are fewer stray points after deviation correction.

The computation of the basic multigrid method is started with an arbitrary approximation on the finest grid. When the basic multigrid method is used to solve the transport of intensity equation(TIE) for phase retrieval, the retrieved phase distribution is sensitive to the initial values on the finest grid. To mitigate the above-mentioned problem, a full multigrid method (FMG) solving the TIE for phase retrieval is presented. Instead of starting with an arbitrary approximation on the finest grid, the first approximation is obtained by interpolating from a coarse grid solution. The coarsest grid is created based on the finest grid using the restrain operators, and the solution on the coarsest grid is gotten. Then the initial value of the fine grid can be obtained through prolongation operator, and the Ⅴ-cycle is adopted to solve the equation on this fine grid. Based on this nested iteration technique, the exact solution to the TIE is obtained. The simulation experiments show that this method can retrieve the complicated phase distributions with high accuracy, and has fast convergence speed.

In order to realize the automatic measurement of the invar rod scale errors, an automatic measurement system of invar rods based on image processing is proposed. The scale line under test is imaged by a microscope. The scale line image is acquired and transmitted to the computer by a digital CCD video camera. Digital image processing technology is used to extract the scale line edges. Then the scale midline position coordinate originated from the first-measured scale line can be estimated automatically. The scale error is calculated out. The uncertainty from measurement repeatability is about 0.79 μm and the extended uncertainty in the measurement is about 3.9 μm which excels the 6 μm prescribed in the national standard. The whole system integrates optics, mechanics, electrics and computer together and can be operated conveniently with high accuracy.

A novel adaptive quantization index modulation digital image watermarking algorithm in contourlet transform domain is proposed. The original binary watermark image is preprocessed through extended scrambling, dimension reduction and pseudorandom sequence encryption. The secret watermark information bits are embedded into low-pass subband coefficients in contourlet transform domain. According to energy distribution in lowpass subband, the largest singular value of the selected lowpass subband coefficients blocks is adaptively operated by quantization index modulation for embedding watermark information. Experimental results show that the algorithm has good imperceptibility and robustness against the attacks of JPEG compression, low-pass filtering, additive noise, resampling and image cropping. Because of quantization embedding strategies, no host image is needed in watermarking extraction, which is a blind watermarking algorithm.

Based on the anisotropic diffusion equation, the disadvantages of high computational complexity and unstability in speckle noise elimination with the existing diffusion algorithms are analyzed. A new algorithm of diffusion direction estimation is proposed. The variances of stripe regions in four directions are adopted as the direction measure of local area in the image. The general and diagonal integral images are adopted for fast computation of the variances. The diffusion quantity of each pixel is determined by the differences between the current point and the eight adjacent pixels together with the weight coefficients in corresponding directions. Meanwhile, the diffusion equation and realization process are presented. Experimental results demonstrate that this method has strong adaptability. It can protect the texture details well during noise elimination, and reduce the consumption of time due to few iteration number.

A multi-target tracking framework is designed to detect small infrared targets under complex backgrounds when the signal-to-noise-ratio (SNR) is low. The infrared image’s optical flow field is calculated, based on which the mathematic methods inclnding segmentation of threshold and mathematical morphological filter are employed to detect the infrared target from the backgrounds. Based on the results, with the target moving continuously, the neighborhood predict arithmetic is used to we eliminate the noise generated in the process of detection. The track prediction method based on Kalman filter is given to solve the problems of target missing and track crossover. This framework avoids the interference of the noise and the confusion of multi-track through the moving characteristic of targets. The infrared sequence images got from long-wavelength infrared camera verify that this framework is effective to track the small infrared targets under complex backgrounds.

The 4f coherent imaging system with phase object (PO) is a new method to measure the third-order optical nonlinearity. Only the PO with uniform phase retardation is used in nonlinear-imaging technique with a PO (NIT-PO) until now. A uniform PO can only produce a single phase contrast signal. Using positive-negative PO, the sensitivity of NIT-PO can be increased. In order to increase the sensitivity of NIT-PO further with positive-negative PO, theoretical investigation about the effects of radius and phase shift of positive-negative PO on the sensitivity of the 4f coherent imaging system is made. The results show that the sensitivity of the system increases with the ratio of PO radius and the aperture radius decreasing. When the size of the PO radius unchanges, the highest sensitivity for nonlinear refraction measurement can be gotton at the position with the phase change of 0.43π.

To carry out the precise measurement of large-scale complex workpieces, accurate calibration of the stereo vision measurement system has been becoming more and more important. This paper proposes a flexible and reliable camera calibration of stereo vision measurement system based on unit quaternions with optical reference bar, which has three small collinear infrared LED feature points and the lengths between these feature points have been precisely calibrated. By imaging the optical reference bar at different locations and orientations over the measurement volume, we can calibrate the stereo vision measurement systems. During the calibration process, we can automatically control the light intensity and optimize the exposure time to get uniform intensity profile of the image points at different distance and obtain higher signal-to-noise ratio. The experiment alresult proves that the proposed calibration method can obtain good results in the application, the maximum measurement error is 0.15 mm and the maximum standard deviation is 0.11 mm.

Prediction of operating range is an important part in designing the visible and near-infrared imaging system. To insure the reliability of the prediction and evaluation, the range prediction method of the optoelectronic imaging system adapted for extended target is studied in this paper. The definition and measurement of minimum resolvable contrast (MRC) is introduced. A mathematical model for range prediction based on MRC is established. The calculation procedure and characteristics of the model are discussed combining an actual system. Compared with the traditional way based on the smallest resolution angle of instantaneous field of view (IFOV), the range prediction model is more reasonable and scientific, because that factors such as characteristics of object and background, atmospheric and transmission path condition, performance of imaging system, human visual system are taken into account. It is an effective approach to evaluate the visible and near-infrared imaging system for onshore, offshore and remote sensing detection.

A new method is presented for detection of chirp direction in ultrashort laser pulses. Based on interference autocorrelation (IAC) of the fundamental frequency signal for a first derivative, the derivative interference autocorrelation (D-IAC) is obtained. This method is highly sensitive to chirp direction. The linear chirp, square and cubic chirp pulses with Gaussian intensity are numerically calculated and simulated, and the derivative interference autocorrelation peak and the valley correspond negative and positive chirp separately. It is found the sine function factor can determine the direction of chirp. Experiments prove the chirp direction in ultrashort laser pulses can be determined by the derivative interference autocorrelation.

Two approaches, single decomposition approach and multi-decomposition approach,using discrete wavelet transform for extracting phase in phase profilometry are proposed. In the former approach, wavelet multi-resolution analysis is chosen to perform discrete wavelet transform of the pattern after converting original signal into the analytic form. The phase distribution is recovered from every coefficient whose modulus reaches maximum in the scale direction at the position. In the latter one, an interpolation to original signal is used to vary the sampling rate and multi-resolution analysis is reused to acquire redundant detail coefficients. The first approach is suitable for sinusoidal fringe pattern. In contrast, the second one is more robust to noise and capable of handling quasi-sinusoidal fringe pattern. Compared with the method employing continuous wavelet transform, these two approaches have 90% and 50% increases in computing speed respectively for a 512 pixel×512 pixel image, and are more appropriate to discrete signal processing. The numerical simulation and experiment have proved the validity of the approaches.

A new method based on phase tracking algorithm and ray tracing algorithm is proposed for measuring the three-dimensional (3-D) shape of object in water. It uses digital sinusoidal fringe to record the information of object's 3-D shape. The phase tracking is taken to define the according points in the deformed pattern captured by the camera and the fringe pattern projected by the projector. Then the object's 3-D shape is calculated with ray tracing algorithm. This method uses 2-D patterned fringe to obtain the 3-D shape of object and the scanister is not needed, so the speed of reconstruction can be greatly increased and the cost of instruments will descend. An actual measurement is done, the perfect results of the reconstructed shapes prove its correctness and feasibility.

A 6-period InGaAsP quantum-wells film has been grown on InP substrate at a low temperature by metal organic chemical vapor deposition (MOCVD). The small signal transmission of the sample at 1.064 μm is 23%. By using it as a saturable absorber and an output coupler concurrently, passive mode-locking operation in a Nd∶YAG laser at 1.064 μm can be realized, and a single pulse train with average pulse duration of 23 ps and energy of 15 mJ was obtained. A Si/SiNx film wich consisted of 4-period quantum-wells structure has been prepared on quartz substrates by RF magnetron reaction sputtering technique and annealed at 1000 ℃ for 30 min in N2 environment. Inserting the sample into the Nd∶YAG laser resonator, passive mode-locking operation at 1.064 μm and a single pulse train with 30 ps average pulse duration can be obtained. Passive mode-locking of using semiconductor multiple quantum-wells film as saturable absorber has advantages of low cost, design and manufacture simplicity, stability and convenience.

Two laser beams with different divergences are obtained using 300 mm and 1500 mm lens. The ionic fragments distributions of the two laser beams are measured by a time-of-flight mass spectrometer. The results show that with the increasing divergence of laser beam, the fragmentation degree of C60, the yield of delayed ionization of C60 and the total yield of the ionic fragment C+n(n＜25) have steeper change depending on fluences. In addition, the yield of delayed ionization has a larger proportion than direct ionization. The experimental results are in reasonable agreement with the latest prediction by multiple photon absorption theory.

In order to obtain a higher power laser pulse in the terminal, it is necessary to conduct spectrum shaping before the seed pulse being injected into the main amplifier chain to compensate the effect of gain narrowing. Based on the spatial distribution of the chirped pulse spectrum in the stretcher, a scheme to shape the spectrum of a narrow-band laser pulse by using a quartz crystal plano-convex lens spatial light modulator is proposed. The flat-topped spectrum is obtained at the output of the stretcher. The spectrum profile can be easily switched from one profile to another by regulating the polarizing direction of the polarizer.

The first-order correction to the field of ultra-short circularly polarized laser was studied. This theory was used to study the dynamics characteristics of incident electron in the circularly polarized intense laser pulse field, and the acceleration phenomenon was found. For the pulse duration τ0≤30, where τ0 is normalized by 1/ω and ω is the laser frequency, the paraxial approximation is basically consistent with the first-order correction. But when τ0>30, the paraxial approximation deviates from the first-order correction. The electron bunch acceleration effect was also confirmed by using the first-order correction when τ0=100 and τ0=300. At last, the energy distribution spatial distribution and as to the pulse duration was obtained. It is also found that the amount of acceleration electrons increases and these electrons can gather under τ0=300.

Experiments on photoionization process of Gd by the atomic vapor laser isotope separation (AVLIS) method were carried out. The theoretic principle of selective photoionization of odd Gd isotope based on the polarization selection rules was also presented. Experiments validate the isotope selectivity with J=2→2→1→0 multistep photoionization of Gd. The effect of the magnetic field and the laser polarization state on the isotope selectivity was studied by the experiment and numerical analysis. When the angle of axes between laser polarization and magnetic field is 90°, the selectivity may be lost easily by an external magnetic field. The selectivity decreases obviously as the magnetic field exceeds 2×10-4 T. On the other hand, the selectivity changes much more slowly when the angle of axes between laser polarization and magnetic field is 0°.

Polycrystalline dysprosium (Dy) doped lanthanum zirconate-titanate (PLZT) ceramics with compositional formula [Pb0.88 (La1-xDyx)0.12][(Zr0.40 Ti0.60)0.96O3] (PLDZT) were prepared by hot-pressed solid-state ceramic method. The influence of Dy3+substitution on phase structure, microstructure, optical property and electro-optical property of the materials was investigated and analyzed. When the doping amount x was 0.1, the optical transmittance of the PLDZT sample reached the maximum value, and the electro-optical effect of the sample transformed from linear effect to quadratic effect. A high quadratic electro-optical coefficient of 5.59×10-16 m2/V2 was examined. To obtain a same variation of di-refractive index Δn, the applied voltage of the PLDZT (x=0.1) sample was decreased obviously.

A modified photonic quasicrystal fiber is designed which has an octagon-fold symmetric quasicrystal array of air holes in the cladding. Small air-holes of the inner two rings and large air-holes of the outer rings in the cladding are adopted. The dispersion properties are analyzed by using the full vector finite-difference frequency-domain (FDFD) method with anisotropic perfect match layer (APML) absorbing boundaries. Its dispersion curve is calculated, when the distance between adjacent air holes is from 1.40 μm to 2.50 μm, the small air-hole diameter is from 0.10 μm to 0.50 μm and the large air-hole diameter is from 0.20 μm to 1.00 μm.The results show that the flattened dispersion at different levels can be obtained by adjusting the diameters of two kinds of air holes and the distance between adjacent holes in the cladding.

By utilizing the self-collimation and co-directional coupling mechanism, an arbitrarily bent beam splitter is designed and analyzed theoretically,which is composed of a self-collimation zone,a coupled zone and two periodic dielectric waveguides. Dispersion relation in the coupled zone is analyzed theoretically using plane-wave expansion method, and the coupled length is calculated. The transmission character of electromagnetic wave in splitter is simulated by finite-difference time-domain simulations, and the steady electric field distribution is obtained. Effective coupling technique of coupling lightwave from self-collimation zone to coupled zone is discussed.The result shows that if the phase matching conditions are satisfied the light can be injected into the coupling section and transferred into the two output branches efficiently, the angle can be bent to arbitrary value, and the transmittance is above 90%. A new method which enlarges the distance of point source and image point based on the designed splitter is proposed.

Two-photon excited fluorescence based on confocal laser scanning system was used to study the cellular localization of 5-ALA induced PpⅨ in DHL cells. Fluorescence probes of rhodamine123, DioC6(3) and LysoTracker Green were used to indicate the cellular localization of 5-ALA induced PpⅨ with a double-labeling method, and real-time image processing was carried out to detect the image edges, extract and segment the information of fluorescence images. By using the simulation of Matlab software, we calculated the correlation coefficient between fluorescence probe image and 5-ALA induced PpⅨ image after a 3-hour incubation time, and the results show r=0.564 for mitochondria, r=0.465 for endoplasmic reticulum and r=0.366 for lysosome. It can be seen that 5-ALA induced PpⅨ mainly distributes in mitochondira, but also in endoplasmic reticulum and lysosome, at least in the lysosome. Two-photon excited fluorescence can be a useful method for quantitative or qualitative cellular localization analysis of 5-ALA induced PpⅨ.

In medicine and biology when the laser is used, the parameters, such as pulse duration, irradiation energy,pulse number and irradiation manner are very important. Light-absorbing nanoparticles that are heated by short laser pulses can transiently increase the membrane permeability. Different laser sources and irradiation manner were used to investigate the transfection efficiency accociated with the laser parameters. After irradiation, the memebrane permeability was evaluated by flow cytometry assaying of propidium iodide (PI) and fluorescein isothiocyanate (FITC) dextran. The mechanism of light-induced damage was studied by thermal modeling. The preliminary results suggest that this laser-induced permeability strategy provides a promising new means of delivering larger exogenous materials such as plasmid DNA into living cells by adjusting the laser parameter.

In order to rapidly and accurately acquire cucumber growing information, such as the nitrogen content and leaf area index (LAI), a multi-spectral imaging technique was investigated. The linear relation between reflectance and image gray value was developed using the calibration board. The gray value of leaf sample was achieved by image processing of green, red and near infrared channels obtained by a three-channel CCD camera. Then the gray value of the leaf sample was transferred into reflectance value by aforementioned experiential linear function. The reflectance value was used for the calculation of vegetation index. Least squares-support vector machines (LS-SVM) model was developed for the relation between vegetation index and nitrogen content, vegetation index and leaf area index. The results indicate that the correlation coefficients of vegetation index and nitrogen content, vegetation index and LAI are 0.8665 and 0.8553, respectively. The overall results demonstrate that there is a close relation between the vegetation index and growing information of cucumber, and the multi-spectral imaging technique is a new powerful method for the acquisition of cucumber growing information.

The effect of time-dependent ionization on two-photon absorption (TPA) cross section of 4,4′-bis (dimethylamino) stilbene molecules is studied, through solving, the Maxwell-Bloch equations using an iterative predictor-corrector and finite-difference time-domain technique. The numerical results show that for a few-cycle femtosecond pulse, the one-step resonant TPA is dominating. The two-photon saturation absorption can be observed. The dynamical TPA cross section is a linearly decreasing function of the input pulse intensity when the input intensity is lower than TPA saturation intensity. TPA cross-section of the medium reduces as the value of photoionization cross section increases at the same propagation distance. The propagation distance has an obvious influence on the TPA cross section. The thickness of the molecular samples thus should be taken into account as measuring the TPA cross section. When the femtosecond pulse is applied to measuring the TPA cross section, conditions for the available analytic expressions are discussed.

Quartz crystal has a biggish temperature expansion coefficient, therefore temperature variation will cause use errors for quartz crystal devices. In order to reduce this error, we study the relation between composite compensator’s phase retardation and temperature variation. The results show that the bigger the temperature change is and the order of wave plate, the bigger the influence on the phase retardation is. The phase retardation and the rotation angle of the polarizer exhibit a linear relation in definite temperature range. The calculated result is well in agreement with experiments. Our results provide a useful referrece for the proper employment of composite compensator under different situations.

In terms of the coupled-mode theory, electro-optic modulation theory, conformal transforming method and imaging method, a transfer matrix technique is proposed for analyzing the high-frequency response characteristics of the polymer directional coupler electro-optic switches. Expressions of output power, rise time, fall time, switching time and cutoff switching frequency are deduced. The structures of waveguide and electrode are optimized for getting the minimum propagation loss, good matching impedance, low switching voltage and high cutoff switching frequency. Simulation results show that the switching voltage is about 1.457 V, coupling length is about 4.374 mm, switching time is about 32.8 ps, and cutoff switching frequency is about 114.7 GHz. Comparisons are performed among the results of this technique, those of the point-matching method, and the experimental results, which show that the proposed technique has high accuracy.

The enhanced transmission phenomenon of 980 nm wavelength light through sub-wavelength periodic hole arrays on Au film was analyzed. A triangular lattice hole arrays model with centric defect mode hole was established. By using three-dimensional finite difference time domain(3D-FDTD)method, the property of transmission has been numerically analyzed. The results show that the transmission with given wavelength can be enhanced by optimizing the periodic parameters of hole arrays. When the period of hole arrays, diameter of centric hole and diameter of air holes are 450 nm, 400 nm, 150 nm respectively, the transmission field can be confined to a spot with sub-wavelength width (880 nm) in 3 μm far-field from hole array surface. The fabrication technology of hole array on Au film by using focused ion beam (FIB) was studied, and the expected hole array was developed. This hole arrays can be integrated onto a 980 nm wavelength VCSEL lasers to optimize the far-field characteristic of the device.

The propagation of two-dimensional (2D) spatial soliton waves in highly nonlocal media is investigated analytically by using self-similar mothod. A broad class of exact self-similar solutions to the highly nonlocal Schrdinger equation is obtained, and it can be described by Whittaker function in highly nonlocal media. The results demonstrate that there exist soliton waves, propagating in a self-similar manner. The higher-order spatial soliton waves can exist in various forms, such as 2D Gaussian soliton family, vortex-ring soliton family, multipole soliton family and defects soliton family by choosing optical soliton parameters. The stability of these soliton clusters in propagation is confirmed by direct numerical simulation.

Optical transport characteristics with different axicon models were studied systematically based on the diffractive and interferential theory and geometry optics. The characteristics of traditional axicon, kinoform-axicon, elliptical axicon and gradient-axicon were simulated and analyzed respectively. Based on the simulation analysis results, propagation-invariant beams with long non-diffracting distance was generated by kinoform-axicon; beams oblique incidence were also converted to non-diffracting beams by elliptical axicon; and bottle beams with much more extensive application can be obtained directly by gradient-axicon.

The focusing properties of partially coherent and circularly polarized Bessel-Gaussian beams through a high numerical-aperture objective are studied. Based on vectorial Debye theory, expressions of intensity distribution and degree of polarization in the focal field are derived. Numerical calculations are performed to compare the different focusing properties of right-circular and left-circular polarized partially coherent Bessel-Gaussian beams. Furthermore, the influence of correlated parameters of the incident beam and the maximal angle of the high numerical-aperture objective are studied in great detail. It is found that the spin angular momentum of the beam will transfer into orbital angular momentum when the circularly polarized beam is focused by a high numerical-aperture objective. It is also found that the focusing properties will be influenced by the correlated parameters studied. The research of this paper is of great importance in the optical micromanipulation field.

This paper theoretically analyzes the electrooptic modulation characteristics of a Kerr medium under two transversely applied electric fields, and hence optical materials exhibiting dual transverse electrooptic Kerr effect are decided. The refractive index ellipsoid analyses demonstrate that the electrooptic phase retardation in some Kerr media is proportional to the square of the amplitude of applied electric field but independent of its direction; and the azimuth angles of the field-induced birefringent axes are only decided by the direction of the applied electric field and independent of its amplitude. This electrooptic modulation characteristic can be named as dual transverse electrooptic Kerr effect. Excluding optical materials exhibiting Pockels effect and electrogyratory effect, the crystals of cubic 432, m3m point groups and hexangular 6/mmm point group, and all the isotropic optical media exhibit dual transverse electrooptic Kerr effect. Transparent ceramic-glass with large Kerr constant has been reported in recent years, and it will accelerate the applications of dual transverse electrooptic Kerr effect in many fields of optical science and technology.

The concept of vectorial controllable dark-hollow (CDH) beams is proposed. The CDH beams can be used to describe circular hollow beam whose axial intensity is not entirely equal to zero. This model has many interesting characteristics that the central dark size of beam can be controlled easily by various parameters, the form simple and easy analysis, propagation properties approach actual case and so on. On the basis of vectorial Rayleigh-Sommerfeld formulas, the nonparaxial propagation analytical formulas of vectorial CDH beams are derived. The paraxial approximation is dealt with as special cases of our general results. By using the derived formulae, the propagation properties of vectorial CDH beams in free space are illustrated and analyzed comparatively with numerical examples. The results show that the vectorial CDH beams keep the hollow intensity distribtuon in the near field and the f parameter and propagation distance play the important role in determining their nonparaxiality.

Some quantum identity authentication(QIA) protocols enable both communication parties to authenticate each other by sharing entanglement or identity keys beforehand and they always go without a certificated authority(CA). Such kind of authentication structure is simple but not easy to extend into integrated network. An authority-based secure QIA protocol is proposed using the robust entanglement of W state. With the help of CA, two legitimated communication parties can identify each other faithfully and simultaneously share the entangled particles for later controlled communication. Security analysis shows that QIA remains secure even confront with several typical individual attacks. The authority-based model ensures the security complete with expandability, practicality and controllability.

Based on geometrical-optics approximation (GOA) of forward scattering by a gradient refractive index (GRIN) sphere, a further extension of the method to the on-axis Gaussian beam scattering of a transparent gradient refractive index spherical particle is developed. The scattering angle of Gaussian beam through the GRIN sphere and the phase shift are deduced and the calculation procedure of the method is given. On the basis of the above work, the scattering intensity distribution is calculated by the extension of the GOA and the result is compared with those calculated by the generalized Lorenz-Mie theory (GLMT). When the beam waist is larger than the particle radius, the discrepancy exists because of the surface wave influence. Compared with our results, the extension of GOA is valid on condition that the beam-waist radius is smaller than the radius of the particle. The comparison between calculation speed of GOA method and the one of the (GLMT) is given. The result indicates that the calculation speed of GOA method is faster.

Axial force exerted on an eccentric sphere by a focused Gaussian beam is studied within the framework of the generalized Lorenz-Mie theory (GLMT). The beam shape coefficients are calculated by integral localized approximation. The translational addition theorems for spherical vector wave functions and the boundary conditions are used in solving the scattering coefficients. Expression and numerical results of the radiation force for an eccentric sphere are given. By reducing the eccentric sphere to a concentric sphere system, the expression of axial force exerted on an eccentric sphere by a focused Gaussian beam is validated. The effects of distance between centers, beam waist, refractive-index and wavelength on axial radiation force are discussed.

There are two types of sampling to obtain fiber Fourier transform spectrometer (FFTS) interferogram, single-sided sampling and double-sided. The techniques for obtaining recovered spectrum from the two types of interferogram sampling are discussed in detail. The mathematical expressions and calculation procedures are proposed. The advantages and shortcomings of each technique are compared. The single-sided recovery algorithm is ameliorated and the phase correction efficiency is improved. The research results are proved through the experiment. The recovered spectra by two algorithms agree well with the standard spectrum, which proves the methods are effective.

Spatial heterodyne spectroscopy (SHS) is an imageable spectroscopic technique with high sensitivity, and it can obtain high spectral resolution. According to these features, a line-by-line calculation method is presented for SHS observations, which is fit for the horizontal sounding of water vapor without other gas absorptions. Absorption coefficients of all lines are computed with Voigt line function, and the halfwidths are also modified to the actual pressure. Average transmittance calculation is done by taking account of line continua, and the density of water vapor can be calculated. The real-test data obtained by FTIR spectrometer covering a range from 1590 to 1610 cm-1 is used to calculate the transmittance. It is compared with the result obtained from Modtran computation, and the method is proved feasible.

In order to identify and distinguish golden saltwater pearls and color-treated golden pearls, Raman spectrum and UV-visible absorption spectrum were used for testing and analyzing. The results show that in Raman spectrum, compared with color-treated one which has more miscellaneous peaks and higher fluorescence background, peaks are found more stable and less miscellaneous in golden saltwater pearls with a much lower fluorescence background. Between 0～1000 cm-1, the base lines of golden saltwater pearls are below 1000, but for color-treated golden pearls, they are higher than 2000. The intensity of 275 cm-1 Raman band in golden saltwater pearls is more stronger than that of the color-treated one, where it has been covered by the fluorescence background; In the near ultraviolet region (200 nm～400 nm) of UV-visible absorption spectrum, characteristic absorption peaks of 284 nm and 357 nm were found in golden saltwater pearls. But those characteristic absorption peaks in spectrums of color-treated golden pearls are missing, wihich are either red shifted (408 nm) or disappeared. According to the differences of Raman and UV-visible spectrums between golden saltwater pearls and color-treated golden pearls, they can be quickly and effectively set apart without any damage.

According to the diagnosis of X-ray polarization spectrum in laser-produced plasmas with wavelength of 0.5～0.8 nm, a new pratical polarized spectrometer is designed and manufactured based on spatial resolution. Two pentaerythritol (PET) flat crystals are taken as dispersive elements, one is set in the parallel channel and another is installed in the perpendicular channel. The imaging plate with effective area of 30 mm×80 mm, is employed to receive the signal, and the optical path is about 240 mm from the source to the detector via the crystals. The X-ray spectrum emitted from the aluminum plasmas was recorded with imaging plates. The helium-like spectral line and lithium-like satellite line and their polarizations were calculated. The reason causing negative polarization is analyzed. These experimental results show that the measured value of the X-ray polarization spectrum matches the theoretical value well, and the polarization spectrometer is good for X-ray diagnoise of polarization spectrum in laser-produced plasma.

The arranging state and second-order nonlinear optical properties of sandwich terbium bisphthalocyanine (TbPcPc*) molecule in Langmuir films and Langmuir-Blodgett (LB) films were investigated by using the surface pressure-area (π～A) isotherm and second harmonic generation method. The mechanisms of nonlinearity were discussed. The experimental results indicate that the TbPcPc* molecules form well-ordered stable monolayer films on interface of water/air, and the TbPcPc* molecules take the face to face orientation for the macrocycles and edge-on configuration in Langmuir films. The dependence of second harmonic generation intensity on the incident angle of fundamental beam was measured. The second harmonic generation signal intensity is very strong and its maximum is obtained at the incident angle of 55°. The second order nonlinear optical susceptibility χ(2) is about 1.64×10-8(esu) and the hyperpolarizability β is about 6.21×10-30(esu). The origin of second harmonic generation is attributed to the electric quadrupole mechanism and the electric dipole mechanism for TbPcPc* molecule.

Antireflective (AR) coatings prepared from colloidal suspensions of silica are porous and quite polar due to residual Si-OH. So the silica coatings readily absorb water or organic vapor which is detrimental to the optical performance. In order to improve the stability of AR coating, two series of antireflective coatings are prepared by sol-gel process with tetraethoxysilane as a precursor. All of them are modified with trimethoxy (3,3,3-trifluoropropyl)-silane and diethoxymethyl (3,3,3-trifluoropropyl)-silane. Experimental results show that hydrophobic performance of the coatings is enhanced significantly. The anti-reflectivity of the coating is high when the mass fraction of CF3-CH2-CH2-Si or CF3-CH2-CH2-Si-CH3 is between 0.40%～1.5%. At a certain mass fraction of fluorine-containing siloxane, the performance of high laser damage threshold is not affected obviously. A series of tests are carried out by exposuring the coatings to vapor contamination in 10-3 Pa vacuum chamber. The test results indicate that the stability and life of AR coatings are improved greatly.

Erbium oxide thin films were prepared at different Ar/O2 flow ratios by reactive radio frequency magnetron sputtering. The optical constant and band gap of the Er2O3 thin films were studied by using spectra ellipsometry and ultraviolet-visible spectra. The dielectric properties and current-voltage (I-V) measurements were carried out on various films. The results reveal that the refractive index, band gap and dielectric constants of the Er2O3 films increase with increasing Ar:O2 flow ratios, but the extinction coefficient does not change with that new ratio. The Er2O3 films deposited at flow ratios of Ar/O2 7∶1 present the best physical properties. The refractive index of the films is 1.81 in the wavelength range of 500～1000 nm. The band gap is 5.73 eV. The dielectric constants is 10.5.

Sc2O3 single layer and Sc2O3/SiO2 coatings were prepared by electron beam evaporation. The surface and the microstructure of the film were characterized by AFM and X-ray diffraction, respectively. The laser-induced damage threshold and laser conditioning effect at 355 nm were investigated. The results show that the Sc2O3 film has wide optical band-gap and cubic phase structure. The laser-induced damage resistance of Sc2O3/SiO2 coatings is limited by the impurity of the source materials.

Stress is a property of thin film material. It's important to develop in-process observation and control it accurately. An instrument for real-time stress measurement based on optical deflection of two parallel light beams was presented. Combined with the crystal monitor, we can observe the evolution of thin film stress in process. This instrument was applied to observe the process of deposition of HfO2 film. The results show that HfO2 films have a stable tensile stress of 360～660 MPa for the given deposition conditions. The tensile stress becomes larger when the vacuum or the temperature of substrate is higher. The stress was affected intensively by the substrate surface, and was stable with the increment of thin film thickness in high vacuum conditions.

The visual data, obtained from the just-noticeable color difference discrimination threshold experiment carried out in CIELAB color space, were used to test the four classical color-difference formulae, CIELAB, CMC,CIE94 and CIEDE2000. The just-noticeable color difference discrimination thresholds of the printed samples’ different color regions calculated by different formulae are different. Except for the grey color region,the CIELAB color-difference is higher than others. For the original forms (kL=kC=kH=1), CIEDE2000 ouerforms others with the best matching with visual evaluation. For the color-difference formulae with optimized kC and kH, the optimized form of CIEDE2000 performs the best especially in the color region of grey and high chroma orange.

Setting or calibrating gamma value is a simple and practical method for controlling color on computer displays. The accuracy of visual estimating gamma value of CRT displays is investigated by using the stripe photometry method. The investigated factors include stability for one subject, consistency for different subjects, influence of stripe with different luminance levels. The estimated results were compared with ones measured by instruments. The experiments were conducted on hp 21″ CRT display. The results show that the same operator’s matching result is very stable and matching values vary little for different subjects, gamma mean values by visual estimation for R, G, B and luminance channels are 2.18, 2.17, 2.40, 2.20, and the measured values are 2.13, 2.05, 2.37, 2.09 respectively. The difference between estimated and measured gamma values is about 0.08. Appropriate choice of stripe with different luminance levels will make visual matching more easily, and the estimated gamma value is more adjacent to the measured value.