In order to test middle and low precision asphere and measurement of asphere during grinding and polishing, a new method by extending the ability of laser tracker is proposed. The testing principle is analyzed, and the testing procedure is devised. The coordinate of several points on the tested asphere can be measured by the laser tracker, and the figure error can be calculated by analyzing the testing data and CAD model of the asphere. An off-axial aspheric surface with the aperture of 420 mm×270 mm is measured by this method, the surface map by this method is consistent to the entire surface map from the null test, and the relative error of the PV and RMS error between null test and this method is 6.22% and 3.37%, respectively. The proposed method provides another quantitive measurement for testing large aperture aspheres without any assistant optics, and the data processing and testing operation are very convenient.

To monitor the velocity of industrial exhaust gas continuously, a parallel double-path flow velocity measurement system was designed, and the related theories on measuring the velocity of stack gas flow was studied based on the light scintillation. A simple phase-screen technique was used to analyze the light scintillation in a turbulent medium, and the expression of optical scintillation cross-correlation was obtained which is used to measure stack gas flow velocity. The path-weighting function of the mean velocity was given. The numerical simulation carried on path-weighting function indicates that it has axially symmetric distribution as Gaussian line shape, and the central velocity of the stack makes greater contribution. The impact of light source spectrum on path-weighting in principle was analyzed, and the preliminary experiments show that, although because the light source spectrum has a certain bandwidth, the path-weighting function has changed, the distribution is still axially symmetric. Based on the path-weighting function, the space distribution of the gas flow velocity in stack can be calculated.

Surface plasmon polaritons (SPPs) propagating along a metal surface corrugated with an array of shallow grooves filled with dielectric are studied analytically. It is shown that the asymptotic frequency of SPPs can be greatly decreased by stuffing the grooves with dielectric, and thus the fields exhibit much better confinement. In the THz frequency range, the influence of the absorption in real metal on the performance of spoof SPPs is also examined. The numerical calculations show that long propagation length and subwavelength field confinement are simultaneously available for spoof SPPs on the real surface corrugated with grooves stuffed by the dielectrics. The good guiding ability of the structured surface at THz frequencies is further verified by numerical simulations of wave transmission. The proposed structure may lead to a new design of devices for routing terahertz radiation in highly integrated circuits.

Silicon-based channel waveguides are poled by thermal poling. A fiber-based (single mode) Mach- Zehnder interferometer is utilized to measure the linear electro-optic effect. Poling conditions (poling temperature, poling time, poling voltage) are optimized in air environment. The results show that, the electro-optic coefficient is rTM=0.059±0.001 pm/V, rTE=0.053±0.001 pm/V at the optimized conditions (-2.4 kV, 406℃, 20 min). At the same time, the waveguide has a lower threshold of poling voltage and poling temperature. An effective electro-optic signal can be observed when poling voltage drops to about 100 V or poling temperature drops to about 80℃. The results also suggest that the electro-optic coefficient increases of 15% at negative poling than positive poling.

In allusion to the current practical problem of small duty ratio, low light energy utilization in infrared focal plane array, the manufacture of square aperture spherical microlens array and integrated application with infrared focal plane array are studied. Starting with the character of microlens arrayinfrared focal plane array, the advantages of square aperture spherical microlens array and round aperture spherical microlens array are compared. The laser direct writing varying dose exposure making technology of square aperture spherical microlens array is proposed, and the mathematical model of photoresist exposure and the square aperture spherical microlens array surface figure functions are established, based on which the direct writing varying dose exposure software is written. Related process experiments are carried out by the model number of laser direct system and plasma etching machine from Changchun University of Science and Technology. The infrared quartz spherical microlens array is made, of which micro-lens element size is 40×40 μm2, spherical radius is 60 μm and element spacing is 1 μm, and then is integrated with the square aperture spherical microlens array with infrared photosensitive array. The results show that the duty ratio achieves 95%, and the utilization ratio of light energy increases from original 60% to 90%. It can be concluded that the way using square aperture spherical microlens array instead of the round aperture spherical microlens array can significantly improve sensitivity, signal-to-noise ratio and resolution ratio of the infrared detector.

Rayleigh backscattering is an important physical process in optical fibers, and the Optical Time Domain Reflectometer (OTDR) based on the rayleigh backscattering, is one of the most important and widely-used optical fiber measuring equipments. Rayleigh backscattering progress with arbitrary input optical pulses in the fiber was analyzed theoretically, the impulse response function was derived on the basis of regarding fiber as a linear system, and backscattered output pulse of square pulse and pulse with vibrating was discussed. For the square pulse, the theory of impulse response was demonstrated by commercial OTDR instrument. For the pulse with vibrating, the experimental results show a good agreement with the simulation.

Because of deficient bandwidth, the space resolution of Distributed Optical Fiber Raman Temperature Sensor (DOFRTS) is low. When the sensing length of fiber is close to space resolution, there is no accurate temperature response. For solving the problems, a new linear algorithm is proposed. Firstly, the relationship between Raman ratio and temperature and the characteristics of frequency response are analyzed, and then a mathematical model is built up for this algorithm. A single-mode temperature sensor system for 10 km long is built up, some related experiments are carried out by using the algorithm. Experiment results are consistent with theoretical analysis, the temperature amplitudes of testing fiber from 3 meters to 6 meters are corrected. The temperature measurement accuracy reaches 1℃ and measuring time is 40 seconds. By applying this algorithm, the limit of bandwidth can be overcome effectively and the system cost is cut down obviously, at the same time, space resolution, temperature resolution and measuring time are optimized.

Based on the mode coupling theory of the titled fiber Bragg grating with the numerical analysis methods, the tilted angle and modulation index on the effection of tilted fiber grating reflectivity spectra of front-back core mode coupling and characteristics of tilted fiber grating reflectivity and transmission spectra for core mode and radiation mode coupling on the condition of different tilted angle, index modulation and grating lengths for different polarization are discussed. The results of the study show that different incident lights with different polarizations are exactly the same for front and back core mode couplings. Incident light of s polarization and p polarization state should be taken into account for the radiation mode coupling, because reflectivity spectra envelope are affected by modulation of extinction coefficient and incident light with different polarizations have different extinction coefficients. Moreover, the greater tilted angle is,the more differences for the extinction coefficient of the incident light with difference ploarization is.

A nonimaging optical design method is proposed based on edge ray principle and ellipse flow-line theory. And a Fresnel reflector for uniform lighting LED tubes is designed through three steps: energy equipartition of LED source, target-source foci map and optimization of optical simulation. The complex relationship among the LED source, reflector and target surface is analyzed, which is helpful to optimization of the design of LED illumination. Results show that the uniform of irradiance on LED tube surface is more than 0.93, and the glare is decreased obviously.

To reveal the error propagation rules of camera geometric specification in stereoscopic mapping more accurately, the relationship between the mapping accuracy and specification difference parameters of dual-linear-array CCD camera is studied. Aiming at the characteristic of dual-linear-array stereoscopic mapping, effects of the geometric specification difference parameters on mapping positioning are analyzed. Based on the space forward intersection formula, the positioning accuracy (PA) model is established, and then the variations of PA with the difference between calibration errors of interior orientation elements are presented. The results show that the effect of the difference between principal point x errors on PA is obvious, and the PA rapidly decreases by 60% when the difference change increases to 2.5 μm from 1 μm. In addition, the effect of the difference between focus length f errors on PA can be almost neglected. The model and relevant conclusions have important guiding meaning for the optimization design and quantification of dual-linear-array CCD camera specification.

The relations of band gap widths of four photonic crystal structures (square lattices of cylinder medium, triangle lattices of square medium, square lattices of square medium and triangle lattices of square medium) and the size of medium are studied by the plane wave expansion method. Then the plane wave expansion method is used to calculate the modes of normal lattices and surface defect lattices, and composite the results. The results show that the band gap width of the same photonic crystal lattice increases at first and then decreases. The maximum of band gap width is obtained. The surface mode curves of the four lattices are all declining as the size of surface medium column increase. The square lattices, comparing with the triangle lattices, could have a larger range to change the size of the surface medium column, but get a smaller surface mode range.

Dispersion relation of 1-D photonic crystal is deduced by the method of transfer matrix, with coordinate transformation of arbitrary Fourier exponent of electromagnetic wave packet which is obliquely incident. By analyzing the dispersion relation, it is easy to find the difference between the first band gap under obliquely incident wave packet and that of plane wave, respectively. Meanwhile, the former gap is located in the latter one, for the former one is narrower than the latter one in width. Characteristic of band gap is obtained under obliquely incident wave packet, by comparing the first band gap structure with that of plane wave considering edge position and width of the gap. The condition of approximately substituting plane wave for wave packet to calculate band gap is analyzed, according to related factors such as different incident angle of central wave vector and angle spectrum of wave packet. The results demonstrate that the first band gap structure is closely related to incident angle of central wave vector and angle spectrum of wave packet. With smaller incident angle, the first band gap structure caused by wave packet would become closer to that of plane wave; and with smaller angle spectrum of wave packet, the width and position of the first band gap is closer to those of plane wave.

An air-slot photonic crystal cavity is studied based on the design of an air-slot in a width-modulated line-defect in a photonic crystal slab. The electric field of the cavity mode is strongly localized in free space. Owing to the discontinuity of the dielectric constant, the electric field of the cavity mode is strongly enhanced inside the slot and the mode volume is strongly compressed. The cavity band structure and cavity modes of this air-slot photonic crystal cavity are numerical simulated and analyzed. According to the resonant frequency and the symmetry of the cavity modes, the first order even mode has both high quality factor and small cavity volumn. Using finite-difference time-domain method, the calculated quality factor is as high as 106 and the mode volume is as small as 0.02 of a cubic wavelength in a vacuum. Additionally, the properties of the first order even cavity mode as a function of the slot width and the radius of the holes are calculated. The resonant frequency of the first order even mode is decreased with the solt width and radius of the holes. But when the radius of the holes are 170 nm, the highest quality factor of the air-slot photonic crystal cavity is obtained.

In order to obtain resonance theory of 1D doping photonic crystal, a resonant cavity model is set up and the analytical formulas of the defect mode frequency of 1D doping photonic crystal is deduced by resonance conditions of the resonant cavity. The physical mechanism of the defect mode of 1D doping photonic crystal is explained. The use of analytical formulas for the variation, which defect mode frequency with the incident angle and thickness of impurities and refractive index of impurities changes, is studied. Resonance theory results and characteristic matrix method results are compared and their results are the same, and the resonance theory is the right way. The resonance theory to analyze variable relationship is convenient, which makes up the deficiency of the numerical calculation method of 1D photonic crystal.

With the development of image fusion technology, various fusion methods are proposed. However, in many cases, the final fused image is observed by human eyes. As a result, fused image quality assessment based on human visual system is particularly important. In order to obtain the objective quality evaluation by simulating human eye perception, a novel method is proposed. First, the source images and the fused image are transformed into CIE L*a*b* color space respectively. Then in the frequency domain these images are filtered by the contrast sensitivity function. The richness of details of the fused image can be predicted by calculating the chromatism of it. With the increasement of the chromatism value, the information details also increase. While the correlation coefficient is evaluated at the same time by calculating the chromatism among the source images and the fused image. The higher the correlation coefficient, the better the fusion algorithm. With these two constrained parameters, a judgement can be given to different evaluation algorithms. Experiments show that the results of the proposed method are consistent with the human eye observation.

A fast Fourier transform method is mainly used in the digital holographic wavefront reconstruction of lensless Fourier transform, but the reconstructed image will not fully lie in the reconstructed area. Based on the recent image plane filtering technique, a method used for enlarge reconstructing object local area wavefield is proposed and the method allows the reconstructed image fully lie in the reconstructed area. Moreover, a digital holographic wavefront reconstruction example of object with fine structure is also given. Additionally, regard the digital holographic wavefield reconstruction as a coherent imaging process of an optical system which has a square exit pupil, we can derive the relationship between the resolution of object enlarged image and the optical system parameters. Finally, experimental results confirm the suitability of the proposed method.

A video target tracking system is designed which is achieved in the embedded platform. The system acquires video signal by using CMOS image sensor, controls video signal in ARM9 processor which is obtained in Z228 multimedia chip, and compresses video signal through MPEG-4 hardware encoder. Meanwhile, the Mean Shift arithmetic is used to track moving target. Considering the convergence limitation, multiple search point is set to improve the tracking results. The operating speed of code is raised through decreasing sampling point and labeling computed points, thus the tracking instantaneity is enhanced. The experiment results indicate that this system can achieve video target tracking continually and steadily at the speed is 27 fps.

The traditional microscope is not suitable to observe the schistosoma cercariae which usually floating on the water surface, because it needs an optical focusing process and the wobble or fluctuation of the water surface is difficult to avoid. The basic concept and procedure of digital in-line holography based on convolution are shown mainly for schistosoma cercariae detection. An auto-focus algorithm based on wavelet transform was improved. The max amplitude of high-frequency coefficients in the focal windows was used to evaluate the definition of the reconstructed image instead of the sum of high-frequency coefficients. The evaluation function was maximal only when the reconstructed distance equal to the recording distance in the simulated experiment, which shows the accuracy of the improved algorithm. The experimental device of digital in-line holography was designed for schistosoma cercariae detection. The experimental results show that the auto-focusing method based on wavelet transform can be used in digital holography, and the digital in-line holography can be used to detect schistosoma cercariae when the water surface is fluctuant. The reconstructed image resolution is equivalent to the resolution of digital microscope with 1X micro lens, and the bifurcated tail of schistosoma cercariae can be observed clearly.

A new non-linear white balance method is proposed. Taking XYZ stimulus and RGB values of each color block in Munsell color chart illuminated by D65 light source as training samples. A BP neural network mapping relation is built between digit-image RGB values of standard Munsell color chart and XYZ stimulus. Then Estevens matrix is introduced, which is used in translating XYZ stimulus to cone stimulus. After non-linear calculation, the results are translated back into digit-image RGB, values and an image after white balance is produced. It is indicated that this method gives a correct result much closer to image of objects illuminated by standard light sources. In the case of high purity light sources, a large volatility exists in adjusting channel-gains, while a stable result using the proposed method. Especially when the purity of the light source is too high to make values of some color channel approach 0, the channels gain method is out of action, while a good correct result still can be achieved. Meanwhile, the mapping relation between RGB values of digit-image and XYZ stimulus is built, which is a still character for different lighting condition.

A scheme is proposed for generating a four-photon polarized Dicke state, Greenberger-Horne-Zeilinger state, and W-type state. The scheme only uses Kerr medium, polarization beam splitters, half wave plates and homodyne measurement on the coherent light field, which can be efficiently achieved in quantum optical laboratories. Strong probe mode interacts successively with multiple signal-mode photons, each causing a conditional phase rotation in the probe mode. Subsequent homodyne measurement of the probe mode will project the signal mode photons into the desired entangled polarization-photon state. In addition, in order to show the power of prepared entanglement as a resource, we further propose an experimental scheme for teleporting an entangled three-photon polarization state, based on cross-phase modulation.

Within the effective-mass approximation, the influences of hydrostatic pressure on the exciton binding energies, emission wavelengths and electron-hole recombination rates for a heavy-hole exciton in strained wurtzite (WZ) GaN/Al0.15Ga0.85N cylindrical quantum dot (QD) with finite potential barriers are investigated via a variational procedure, with considering the strong built-in electric field (BEF) effect and strain dependence of material parameters. Numerical results show that the exciton binding energies and electron-hole recombination rates both increase almost linearly, and the emission wavelengths are monotonically reduced with the increase of the applied hydrostatic pressure. The hydrostatic pressure has a remarkable influence on the exciton binding energy and electron-hole recombination rate for the QD with a small size. Furthermore, the height of GaN QDs must be less than 5.5 nm for an efficient electron-hole recombination process due to strain effects.

By virtue of the thermo field dynamics and the coherent thermo state representation, the Wigner function of mesoscopic RLC circuit at finite temperature was obtained, and the quantum fluctuations of mesoscopic RLC circuit at finite temperature were studied. By means of the Weyl correspondence and Wigner theorem the marginal distribution of Wigner function in mesoscopic RLC circuit was discussed. The physical meaning of marginal distributions′ statistical average of the Wigner function was explained. The results show that the quantum fluctuations of both charge and current of mesoscopic RLC circuit at finite temperature increase with the rising of temperature and resistance value, and the mesoscopic RLC circuit has squeezed effects between charge and current, caused by the quantum mechanical zero-point fluctuations; the marginal distributions′ statistical averages of the Wigner function are the energy stored in capacity and in inductance of the mesoscopic RLC circuit, respectively.

Signaling is an important part to the communication system, as well as quantum mobile communication. However, the handover strategy to quantum mobile communication signaling in adjacent cells has been researched. Quantum entanglement is the basis of the future quantum mobile communication. With the change of the position of mobile users, the entanglement degree between users and base station changes constantly. A handover strategy based on entanglement degree calculation quantum signaling in adjacent cells is proposed. Firstly, the relationship between signaling entanglement degree and distance is defined. Secondly, changes of signaling entanglement degree in adjacent cells is studied due to the change of the position of users, and a handover algorithm based on the threshold value of entanglement degree is proposed. The simulation results show that the proposed signaling handover strategy can obtain high reliability and realize smooth handover between base stations. Therefore this research will play an extremely important technical support role and standards set in constructing the signaling system quantum mobile communication network.

In a sense, quantum teleportation by which information could only be transferred in one-way is not a perfect mode of communication. Thus, a scheme of two-way quantum communication controlled by a third party is proposed. Firstly, both sides of communication need accomplish information encoding through some unitary transformations. Then they should perform Bell-state measurements(BSMs) to their own qubits respectively, and announce the measured results. With the permission of the controller, two sides of communication could realize the quantum dialogue without divulging information to controller. Because of the join of a third party, safety of quantum dialogue is greatly enhanced, which makes this scheme better. According to the realization of secure two-way quantum communication, the scheme may be a good reference in practical application of quantum secure dialogue and quantum private communication.