The dependence of a fiber Bragg grating strain sensor on the improved structure parameters was investigated both numerically and experimentally. The stress distribution and the strain of the grating region was obtained. In the case of the overall width and thickness are equal, the sensitivity of this structure is about 600 times higher than the traditional I-shaped structure. The influence of the 6 key structure parameters on the strain sensitivity and the measurement range was analyzed in detail. Experimental results were also given compared with the numerical simulated results. The gratings were packaged respectively with UV glue and glass solder to get the sensitivities were: 249 pm/N, 330 pm/N and 1.1 pm/N. The analysis method and data provided a basis for structural optimum design of fiber Bragg grating strain sensors in different applications.

The open-loop all-optical chaotic communication system based on a fiber channel is established according to the equations of semiconductor laser with external feedback and fiber transmission. Two encryption methods for message, i.e. chaotic modulation and chaotic shift keying are considered. The advanced adjusted subtraction demodulation method is used to recover the encrypted message. Meanwhile, the performance of the system is measured by the decoding Q factor. Four kinds of fiber channel are constructed by setting single mode fiber and dispersion compensation fiber in different orders. The influence of the structures on the communication performance of the system is analyzed by numerical simulation. The result indicates that reserving a small negative accumulated dispersion in the fiber channel helps to improve the performance of remote transmission. The two symmetrical structures, i.e. middle and two-side compensations, have similar performances. The Symmetrical structures are superior to the asymmetrical structures, i.e., anterior and posterior compensations, and therefore suitable for the application of remote and high-speed open-loop all-optical chaotic communications. In addition, the chaotic modulation method is always superior to the chaotic shift keying method for the remote and high-speed chaos laser communication whatever the structures of the fiber channel are.

Three peak-detection algorithms (cubic spline interpolation differential method, Gauss polynomial, Gaussian fitting algorithm) for fiber Bragg grating reflection spectrum were analyzed and compared. It is demonstrated that Gaussian fitting algorithm produces the lowest error under the same sampling conditions; when the uniform sampling number is 250, the errors of three peak-detection algorithms are respectively 3.4 pm, 13.0 pm and 2.6 pm. The idea of non-uniform data sampling method to search peak was proposed. Sample the actual FBG reflection spectrum with uniform and non-uniform sampling method, and search peak using the three peak-detection algorithms respectively. It can be concluded that the error of a certain algorithm by non-uniform sampling is lower than by uniform sampling method; when the sampling number is 250, FBG peak error of Gaussian fitting algorithm under non-uniform sampling method is reduced by 38.46% than uniform sampling method.

The main characteristic of WDM-PON is the node-tree structure. In order to preciously locate faults in each branch, a method based on tunable chaotic Fabry-Perot laser is proposed. Chaotic light emitted from a optical feedback multiple-longitudinal mode Fabry-Perot semiconductor laser diode is utilized as the probe beam. By selecting the feedback mode, a tunable chaotic laser is obtained. The branches of the optical networks are distinguished by the laser′s wavelength, and fault location is realized by calculating the cross-correlation of transmitted and back-reflected signals. In the experiment, we analyse the chaotic property and take a 1×4 ITU WDM-PON to be detected, the measurement results show that the breakpoints and connectors could be preciously located, an rang-independent spatial resolution within 4 cm are achieved with this method.

Rayleigh Brillouin optical time domain analysis system can be operated with single laser and single end of sensing fiber in a non-destructive way, and the modulation of pulse base and pulse with an intensity-type electro-optic modulator is the key technique for obtaining continuous light and pulse light required by the system. A new modulation method with a pulse applied to the bias port of electro-optic modulator and a microwave applied to the RF port of the electro-optic modulator to modulate the pulse base and pulse is analyzed theoretically, simulated with computer and studied experimentally in this paper, and the optimal operating point of electro-optic modulator in Rayleigh Brillouin optical time domain analysis system is discussed. The results show that if the operating point of electro-optic modulator is set at the valley and peak of its transmission curve respectively and the amplitude of microwave modulation signal is chosen appropriately according to the configuration and performance of the actual system, then the continuous light and pulse light meeting the requirements of Rayleigh Brillouin optical time domain analysis system can be obtained when the pulse base and pulse are to be modulated. The results of this study can provide a theoretical basis for the optimal design of Rayleigh Brillouin optical time domain analysis system.

The buried parallelogramic grating is to embed tilt dielectric film in the waveguide with sub-wavelength cycles. Based on rigorous coupled-wave analysis, the grating is modeled and numerically analyzed. The diffraction efficiency under different polarization states and incident angels is calculated. The result shows that with the TE-mode incidence, the 1st order diffraction efficiency varies between ［0, 37%］ with the film thickness and stays almost the same with the change of incident angles. The other non-zero orders′ efficiencies are below 2%. This feature could satisfy the increasing efficiency required in the head-up display. It could also reduce the energy loss and unwanted image rays. When the incident angle changes between ［45 °, 70 °］ in vertical and ［－15 °, 15 °］ in horizontal, the 1st order diffraction efficiency stays almost the same to maintain the uniform display in different view fields. The effect on the diffraction efficiency is also discussed with the change of polarization, inclination, cycle and materials. This article can provide theoretical guidance in the manufacture of the grating.

A grating is a key component of the monochromators, and its aberration correcting ability is a decisive factor for the properties of the monochromators. In this paper, a spot diagram method with the genetic algorithm is studied. The genetic algorithm is applied to optimize the merit function for its strong ability to search the extremum of nonlinear functions. A comparison between this method and the damped least squares method is given, and the result shows that the proposed method is much superior to the damped least squares method.

A fore hyperspectral imaging zoom system is designed. The working spectrum is from 400 nm to 1 000 nm, the F number is from 3.5 to 5.6, and the full field of view at 28 mm focal length and 80 mm focal length is 7.88°and 2.76°respectively. There are two differences between the fore system and the traditional zoom system. First of all, because AOTF is applied for beam splitter in this hyperspectral system, the MTF after beam splitting will be highly focused on. Consequently, the MTF should be evaluated discretly. And, the fore system and the back imaging module will be applied together to reach the total zoom purpose. The two systems will both have certain constructions on the MTF of the total system.So the evaluation of fore hyperspectral imaging zoom system should consider the reseanable requirements of back imaging module and the total MTF,which will be constrained by the detector and thershold of visibility. After considering the above factors, the iamge quality evaluation indicators of the fore hyperspectral zoom system are analyzed in detail. The initial structure of system is calculated from principle of exchange object and image. And it is optimized with software of ZEMAX. The design result shows that the image quality of system can meet the design indicator requirements under every focal length position and every hyperspectrum.

To satisfy the projection demand of cinemas with different size, based on mechanical compensation theory, a digital cinema projection lens is designed, and the cam curve is provided. The lens consists of four groups of nine glass lenses, and all the lens surface is spherical. Through comparing with the classical projection zoom lens, the character of the lens designed in the article is introduced clearly. Focal length is 26~28.3 mm, the relative aperture is 1/1.7, the total length is 158 mm, and the caliber is 71 mm. Distortion is less than 2%, at the frequency of 44.6 lp/mm, the axile MTF is higher than 0.68, the meridian MTF of the largest field is higher than 0.38, and the saggital MTF of the largest field is high than 0.58. The design results show that this lens has the merits of high brightness, steady image surface, compact structure and easy to process.

The optical design of fish-eye lens used for monitoring is discussed. First, based on the system requirment, the equidistance mapping mode in which the directional information of object can be deduced directly from image is selected, then the full frames imaging form is chose for it′s relative longer focal length, which can satisfy the resolution demands of system. Through arranging the configuration and choosing materials rationally, the abberations of system are corrected efficiently. And the drop-off of illumination at the full field of view is alleviated by increasing the pupil coma intentiaonally. Finally a wide spectral fish-eye lens is presented, whose operating wavelength range is from 486 nm to 900 nm, field of view is 180°, and F number is 2.8. The design results demonstrate that the MTF at Nyquist frequency 63 lp/mm is higher than 0.3, the illuminance at the edge field of view is higher than 50% of central field of view, and the f-theta distortion is less than 3%. All indexes satisfy the commands of system.

The Q-type novel aspherical polynomials and its advantages are introduced in the aspect of algorithm, fabrication and manufacturing relative to the traditional aspherical polynomial-based aspheres. The Q-type formulation is applied to design a panoramic lens based on the relationship of super short-focus panoramic lens′ focus and resolution. The designed panoramic lens′ focus is 0.657 mm and ratio of focus and image height is less than 0.184, which includes 4 aspheric surface. This result shows that the spatial pixel of scenic circle area with half vertical field 45°~90° is up to 1.163 7 mm/(°), and the modulation transformation function is greater than 0.3 at the spatial frequency of 227 lp/mm. The result demonstrates the Q-type formulations is certain advantages in super short-focus panoramic lens.

In order to get fine stability of the optical reflector of space remote sensor under the lunar-based environment of force and thermal constraints, base on the inclement environment of force and thermal constraints where lunar-based extreme ultraviolet camera is under, a reflector subassembly meeting lunar-based environment is designed. The finite element analysis of the reflector subassembly show that the first resonant frequency of the reflector subassembly is 354 Hz, the RMS value is 3.62 nm and 2.46 nm under 1 g gravity and ΔT=50℃ temperature change, the result shows the surface accuracy of reflector meets the needs of imaging quality. At last, through the statics surface accuracy detection, mechanical testing temperature tolerance test and imaging resolution test, the result shows RMS value is less than 14nm and meets the design require. It demonstrates that the reflector subassembly structure is reasonable.

To get a new type of automotive light source with high efficiency, better heat dissipation and small volume, LED source filled with cooling, low-viscosity, non-corrosive, electrical insulating and transparent liquid was studied especially on its optical properties. According to GB25991-2010 regulation, high-power white LED of 1300 lumens was chosen as the light source, and ellipsoidal glass shell was chosen as its basic lamp shell. By adjusting position of light source and modifying the shape of glass shell, optical designing program Tracepro was used in designing one projection-type LED automotive source. The results shows that, at the present stage when 40~50 mm diameter glass shells are introduced, illumination distribution of this liquid lens can meet the requirement of GB25991-2010 regulation for high-beam. Energy collection efficiency can reach 86.5%. The illumination intensity of experimental testing is matched with this simulation results.

Based on the finite-difference time-domain method, the optical forces between two ellipsoidal silver nanowires and the physical mechanism were investigated. The effect of the relative position and the dimention of two ellipsoidal silver nanowires on the optical forces were analyzed. A slight change of them would result in an obvious change of the optical force. The silver internal electrons were oscillated due to local coupling resonance. The plasma resonance would convert the photon energy in cavity into the kinetic energy of electronic collective oscillation. The electromagnetic field energy was reduced to negative state, which caused the contractive and negative optical force. Therefore, ellipsoidal silver nanowires attracted each other.

Based on the finite difference time domain method, factors and physical mechanism of different kinds of common metal nanoparticles are studied that influence the absorption efficiency of organic solar cells. With the analysis of field distribution of localized surface plasmon resonance stimulated by metal nanoparticles, effects of metal nanoparticles in different functional layers on the absorption efficiency of organic solar cell are compared. According to Mie theory and electrical resonance effect, the relationship between the structural parameters of metal nanoparticles and the influences they have on the position and intensity of localized surface plasmon resonance is found, and an optimized design of organic solar cells is proposed. The result shows that when small and highly symmetrical metal nanoparticles are closely packed into the active layer of a solar cell, more than three times light absorption enhancement can be achieved.

Entanglment properties of photon-added two-mode entangled coherent states are analyzed and analytical expression of the concurrence entanglement is obtained. The results show that the concurrence of the photon-added entangled coherent states is very sensitive to the superposition phase. Schemes for preparation of photon-added coherent states and photon-added two-mode entangled coherent states are also proposed. The preparation procession of the photon-added coherent states is that the photon-added coherent states are firstly tansformed into a superposition state of coherent state and vacuum state (the superposition coefficient is associated with amplitude of the coherent state ), then by applying the interaction of atom inside high-Q cavity with a classical light, finally added coherent states of cavity field is prepared. Preparation of photon-added two-mode entangled coherent states of cavity fields is based on interaction of the flying atom with two cavity fields.

In this paper, the Tavis-Cummings(TC) model is generalized to simultaneously consider atomic motions and fields via intensity dependent coupling. Evolution of the fidelity of quantum states of entangled two-atom with motion interacting with light field via intensity-dependence coupling is investigated by means of the full quantum theory. The effects on the evolution of the fidelity of quantum states from the initial entanglement factor  of the two-atom and the average photon number n－ and field- mode structure parameter p of the field are researched by numerical calculations. The formation rule of quantum echoes of two-atoms is analyzed, and its physical essence is revealed. The results show that period quantum echo of the two-atom is always produced in the case of field-mode structure parameter p=1, independent of light intensity n－ and the initial entanglement factor  of the two-atom. Bell-state atoms can produce quantum echo with 2π/p cycle on the conditions of strongly coherent field, via changing the p of from 1 to any value less than 800. When p≥800, no matter what value of  takes，the light field is a vacuum field, weakly coherent field or strong coherent field, the fidelity of quantum states of the two- atom is always 1, that is the first class Bell state-atoms is in the fidelity state continuously. But when the initial entanglement factor  of two-atom is 3π/4, no matter how both values of n－, p are, the fidelity of quantum states of the two-atom maintains 1, namely the two-atom is in the fidelity state of the second class Bell-state continuously. The conclusions show that the extension model has good properties of periodic quantum echoes of two-atom, and provides the theoretical parameters and physical carrier for high fidelity output of entangled two-atoms information and experimental implementation of quantum information processing in the noise environment.

A novel infrared image edge detection algorithm based on cellular neural networks on FPGA is proposed. First, the infrared image input module is to build with simulink. The relevant information of infrared image head is acquired, and the infrared image pixel value range is adjusted. Then CNN IP core is designed by lookup table which is created by the template of cellular neural networks. With the regularity and interconnection locality of cellular neural network array, the CNN IP core will be expanded into the cellular neural network array. Then the cellular neural network array is related with the infrared image input and output module by modelsim, so that the infrared image will be processed in real time. The experimental results showed: In the field programmable gate array hardware processor platforms such as the Virtex-6 FPGA of the Xilinx, the infrared image edge detection algorithm will be implementationed with cellular neural networks. The highest frequency of 142.693MHz is got, and the system processing speed of 2.378Mpixels/sec is reached.

Comparing to the linear scanning space camera in low satellite orbit，images captured by the area array staring imaging system in geostationary orbit usually emerges more blur because of the satellite vibration in the relative longer exposure time. To eliminate the motion blur degradation, the paper proposed to capture multiple short-exposure images and fused them on sub-pixel scale instead. The imaging system in geostationary orbit includes the feature of staring at the same area for a long time. Therefore the task mode of time-sharing short-exposure could get multiple less blurred images of the same area. Next, the sub-pixel displacements between the different frames are estimated by image registration algorithm with 0.1 pixel accuracy. And then, the images are fused to improve the low signal-to-noise ratio because of the short-exposure. Excellent results have been obtained by the sub-pixel image registration and image fusion in the paper.

A novel image transforming method called Reconstruction Transform is proposed, which can make the double random phase encryption image become non-negative integer value. Reconstruction transform includes two stages, pre-processing and spectral shifting. It′s major characteristic is that, compress the interger image to become complex image of half-sized before applying spectral transform to the original image, thus reducing the calculation space in the following steps. The proposed method has the advantage of joint image compression and encryption. Compared with the chaotic image encryption scheme, the cipher-text image of the proposed scheme has lower information entropy. Experimental results show that this method has high security, the decrypted image of this method has little distortion and the cipher-text image has a certain degree of robustness to additive noise attack.

Electronic image stabilization still exists some problems, such as high time-consuming，low accuracy, high eror matching probability and so on. The paper takes appropriate measures to solove these problems from two aspects: feature points extraction and matching. Firstly, the FAST algorithm is adpoted to extracte the feature points, and positional precision of the feature points is improved to the level of sub-pixel. Then the RANSAC algorithm is used to eliminate the error matched points, avoid the interference of relative movement, and the global motion parameters calculated is more accurate. Experimental results show that a more higher precision and faster speed is obtained, which can also be applied for the complex shaking video containing translation, rotation shake and relative movement.

In this paper the optical properties and spectral reflectance characteristics of multi alkali photocathode were illustrated and spectral reflectance curve of multi alkali photocathode were measured. The shape of spectral reflectance curve is irregular compared with ordinary optical film. The reason is that the cathode layer absorbs light. Interference peak of spectral reflectance curve is the results that the reflection light on the interface between the glass and the cathode layer and the reflection light on the interface between the cathode layer and vacuum interference together. According to interference theory, if two beam light reflected by the cathode film have the optical path difference of even times the λ/2, interference enhancement peak on spectral reflection cure will appear. Similarly, if two beam light reflected by the cathode film have the optical path difference of odd times the λ/2, interference decreased peak on spectral reflection cure will appear. According to the interference theory and peak wavelength on spectral reflection interference curve the cathode film thickness of the super second generation image intensifier can be calculated out. The thickness is about 191nm, and increased by 38% compared with the second generation image intensifier. Determination of thickness simply by observing cathode film color was not an accurate method. Practice has proved that, the method to calculate the cathode film thickness by using spectral reflectance method is simple and effective. If the spectral reflectance were monitored during the process of cathode production, then the thickness of cathode layer would be able to control precisely, and the cathode study would be more in-depth, cathode sensitivity would be further improved.

To explore how the degree of cathode oxidation influences the ignites characteristics of ring He-Ne laser, photoelectric retarding potential method is used to investigate the variation of the work function with the cathode oxidation. As the cold cathode of discharge device, aluminum′s work function and the work function variation before and after oxidation are measured under the high vacuum conditions by Лукирский spherical photo electronic measure equipment and parallel electrodes optic-electronic & discharge device. The experimental results show that work function of aluminum cathode in the natural oxidation is 2.60±0.2 eV.The mass percent of oxygen on aluminum cathode surface is 3.2%.At different times of oxidation process, the work function of aluminum cathode decreases with the growth of the oxidation time. The reasons that work function measurements of aluminum cathode may be in 2.5～4.3 eV are explained. The conclusion from the experimental results is the oxidation time is longer, the smaller the work function of the material, the more conducive to the ignition of the ring He-Ne laser within a certain range. Cathode oxidation also affect the ignition voltage and the cathode potential drop of gas discharge process .So the choice of the optimal oxidation time ought to consider these two factors.