The systems of optical OFDM high-speed transmission over single-mode fiber and multimode access network by employing the long LDPC coding technique were investigated. The dispersion and frequency selective fading effects of optical fiber link were theoretically analyzed, and the transmission performance of LDPC coded OFDM signals with three different rates in the long-distance transmission and multi-mode fiber access networks through the numerical simulation were compared. Simulation results show that the coded modulation technique of long irregular LDPC coded OFDM with 0.75 coding rate is the most effective for long-distance single mode fiber transmission and multi-mode fiber access networks.

A triplexer was fabricated based on asymmetric Y branch waveguides Cascade Multimode interference(MMI) for fiber to the home(FTTH). The simulation results of spectral response show that output optical fields are clearly. And the demultiplexing function for download 1 490 nm and 1 550 nm and multiplexing function for upload 1 310 nm were achieved. The simulation results of finited different beam propagation method (FD-BPM) show that insertion loss is less than 1.49 dB; the bandwidths of three response wavelengths meet the demand of ITU. 984 completely; the isolation for 1 310 nm is more than 47 dB; the isolation for between 1 490 nm and 1 550 nm is more than 29 dB.

The influence of Bragg fiber design parameters on photonic bandgap was discussed via the finite element method. The theoretical results show that the bandgap move to long wavelength when the thickness or the refractive index of the Ge-doped layers increases. A novel W-shape-core Bragg fiber was firstly proposed by introducing a F-doped low index layer adjacent of fiber core. The calculation demonstrates the W-shape-core Bragg fiber can reduce the confinement loss and improve the bending-resistant ability effectively. A W-shape-core Bragg fiber was designed with a core diameter of 30 μm, which has a loss of 0.1 dB/km at wavelength of 1.06 μm and is proved single mode propagation theoretically.

Characteristics of narrowband and wideband spun fiber circular polarizer were numerically analyzed based on spun fiber coupled-mode theory. Influence on the minimum operation length of the narrowband circular polarizer by such factors as polarization state of the incident light, intrinsic linear birefringence and spin rate of the spun fiber were studied. By use of multi-cladding fiber analysis method, influence on the operation bandwidth of the wideband circular polarizer by the various parameters of the spun fiber was analyzed also. The results show that the minimum operation length of narrowband circular polarizer is dependent on the inherent linear birefringence and the spin rate of the fiber, and is independent on the polarization state of the incident light. Changing the spin rate can adjust the bandwidth of the wideband circular polarizer, and changing the distance between the fiber core and the stress zone can lead the central wavelength of it to change accordingly.

The original materials matching of optical fiber image bundle should be optimized to get better light and imaging propagation. The material of the large radius cation was employed such as PbO as fiber core, the low refractive materials SiO2 and B2O3 as cladding layer and the high acid-leaching rate material such as BaO as the acid-leaching layer. The matching of physico-chemical and optical performance among fiber core, cladding layer and acid-leaching glass materials were analyzed and designed. The optical and calorifics performances of three glass materials were tested and analyzed by the experiments such as differential thermal analyzing and spectrum transmission rate testing, then the original materials formula of the acid-leaching optical fiber image bundle were desined optimally. The result shows that the matching performance is the best when the contents of 45% PbO, 60% SiO2 and 40%(B2O3 +BaO)or over the contents are led in the fiber core, cladding layer and acid-leaching glass individually.

In order to realize preferable white light-emitting diodes with high color rendering index and optimized luminous efficiency, white InGaN/GaN multi-quantum-well dual-wavelength light-emitting diodes (LEDs) were grown on (0001)-oriented sapphire substrates by metal-organic chemical vapor deposition (MOCVD). Photoluminescence and electroluminescence properties of dual-wavelength LEDs with different In content were also studied. The experimental results indicated that In component plays a critical role on stability for electroluminescence spectrum and luminous efficiency of the dual-wavelength LED structures. In addition, YAG∶Ce phosphor-converted white light emission with high color rendering index was achieved using dual-blue emitting active regions.

The carrier density mobility in organic electron transporting semiconductor is very low compared with the inorganic semiconductor, which affects the efficiency and luminance of Organic Light-emitting Devices (OLEDs). To improve the performance of OLED, the electron injecting and transporting ability should be enhanced, and n-type electrically doping can enhance the electron transporting ability of the orangic materials. Li3N was used as n-type dopant and Alq3∶Li3N doped layer was used as the electron injecting layer for OLED. As a result, the performance of OLED were improved. The optimal doping concentration and the thickness were 5% and 10 nm, respectively. Because Li3N is stable in the air and can decomposite to Li atoms and nitrogen at a low temperature and pressure, the disadvantage can be avoided of the effecting of moisture and oxygen to the metal dopant such as Li and Cs. The research result is also helpful to the preserve and doping process.

The fabrication of a kind of inverted bottom organic light-emitting device was reported,using Li3N doping layer Alq3∶Li3N as electron injecting layer. The structure of this device is ITO/Alq3∶Li3N/Alq3/NPB/MoO3/Al. In this device, ITO glass was used as transparent cathode, Al as top anode, the Li3N n-type doping layer Alq3∶Li3N was inserted the ITO cathode and the electron transporting layer, the electron injecting and transporting ability of this device was improved. And 10nm MoO3 was inserted as the buffer layer between Al anode and hole transporting layer NPB, and the hole injecting ability of this device was enhanced. Experiments show that the device with this structure performs as well as the organic light-emitting device with traditional structure such as ITO/NPB/Alq3/LiF/Al. This device can be used in amorphous silicon thin film transistor active matrix organic light-emitting device display.

In order to theoretically improve the conversion efficiency of amorphous silicon solar cells, this article uses AMPS (Analysis of Microelectronic and Photonic Structures) mode was used to module the a-Si solar cells with a structure of TCO/p-a-SiC∶H/i-a-Si∶H/n-a-Si∶H/metal. The intrinsic layer thickness, band gap, doping concentration, defect density of states and other factors were analyzed and compared on the performance of solar cells. The simulation results are as follows: when the work function equals to 5.2 eV, band gap is about 1.8 eV, the intrinsic layer thickness is 265 nm, and amorphous silicon solar cell′s conversion efficiency can be 9.855%, which is almost 2% more than the average conversion efficiency of amorphous silicon solar cells.

Based on the local field enhancement of noble metals, the effect of silver nanoparticles on spectroscopy properties of rhodamine B was investigated by transmission electron microscopy and UV-Visible spectroscopy and spectrofluorophotometer. Furthermore, the interactions among electrolyte ions and silver nano-particles and rhodamine B were studied. The results indicate that the fluorescence of rhodamine B increased first and then decreased when the silver nanoparticles were added into the 0.6 μmol·L－1 rhodamine B. The fluorescence of rhodamine B always decreased when the concentration of rhodamine B is over 0.6 μmol·L－1. The electrolytes, including KNO3, KCl, Ca(NO3)2, MgCl2and CaCl2, led to the formation of large particles and aggregates in the solution. The effect order of electrolytes on the aggregates of silver nanoparticles is CaCl2>MgCl2>KCl>Ca(NO3)2>KNO3. With the increasing of the electrolyte content, the fluorescence intensity decreased first and then increased until to the constant value. The dependence of electrolytes on the fluorescence intensity of the rhodamine B -Ag solution follows the order of Ca(NO3)2>CaCl2>MgCl2>KCl>KNO3.

A series of (100-x)(GeTe4.3)-xAgI(x=5, 10, 20, 30)chalcogenide glasses were prepared by traditional melt-quenching method. The density was obtained by the Archimedes principle. The thermal property was analyzed by XRD diffraction and DTA curves. The optical property was analyzed by UV-VIS-NIR absorption spectrum and Infrared transmission spectrum, respectively. The results show that with the increasing of AgI content, the density of the glasses increases from 5.591 g·cm-3 to 6.314 g·cm-3 and the glass system has high refractive index from 3.73 to 5.70. The glass samples are amorphous, resulting in a wide composition range of glass formation. A maximum glass transition temperatures value of Tg (206 ℃) was obtained for x=5. A red-shifting occurs in the short-wavelength absorption cutting-off edge and the infrared cut-off wavelength is nearly unchanged. The infrared transmission edge is beyond 25 μm, which provides an important candidate for the development of far-infrared Te-based chalcogenide glass materials.

Texturing of multicrystalline silicon were prepared by isotropic acidic etching. The mixtures contained hydrofluoric acid(HF) and nitric acid(HNO3), with NaH2PO4.2H2O solution added as diluents. Texturing of multicrystalline silicon were analyzed by SEM, AFM and ultraviolet spectrophotometer, and the mechanism of silicon etching was preliminary discussed. The results show that the surface of multicrystalline silicon being etched has uniform etched-pits and efficient light trapping with NaH2PO4.2H2O solution added as diluents in HNO3/HF mixture. Optimized the conditions, etching rate can control about 2 μm/min, and it meets requirement for industrial production. In HF-rich HF/HNO3 mixtures the surface of multicrystalline silicon easily form etched-pits with sharp edges, more or less small hole，and the lowest reflectance can reach 16.5%～17.5％. In HNO3-rich HF/HNO3 mixtures the surface of multicrystalline silicon form shallower etch pits, larger size bubble-like texture or polished Si wafers and the higher reflectance.

In order to investigate the mechanism of energy transfer and fluorescence properties of Sm3+/Eu3+ co-doped system,the samples of Sm3+/Eu3+co-doped in LaOF nanocrystals were synthesized by using a hydrothermal-sintering technique.The characterization results of XRD and TEM show that the structure of the nanocrystals is hexagonal,and its size is about 70 nm.Using 442 nm laser to pump the LaOF:Sm3+/Eu3+ nanocrystals,the energy transfer effect from Sm3+ ions to Eu3+ ions was completed,and the fluorescence emissions originating from the 5D0 level of Eu3+ were observed.The luminescence properties of the LaOF:Sm3+/Eu3+ nanocrystals system were analyzed with a spectroscopic method.It was found that the energy transfer results from the relaxation from the 4G5/2 state of Sm3+ ions to the 5D0 state of Eu3+ ions,and the efficiency of the energy transfer increases with the increase of the concentration of Eu3+ ions.

The transition matrix method was adopted, and the transmissivity of TE wave and TM wave were analyzed when incident angle greater than full reflection angle, to study the total reflection through effect of light in one-dimensional(1D) photonic crystal.The total reflection through effect was found in the transmission wave. Response curves of the through effect versus incident angle, response curves of the through effect versus wavelength, and response curves of the through effect versus medium thickness were obtained. Total reflection through effect of light in 1D photonic crystal was also explained by the theories of quantum and evanescent wave.

Novel feature of guided modes in the chiral nihility (the permittivity and permeability are simultaneously zero) cladding fiber were investigated theoretically. The electromagnetic fields in the chiral nihility cladding fiber were presented. Dispersion equations and power of guided modes were derived. Dispersion curves of guided modes were plotted for different chirality parameters. The effect of chirality parameter on power was discussed. Some novel feature are found: surface wave mode and single-mode operation region, double propagation constant, mode intersection and energy store, especially, exotic backward wave mode of which the power is negative both in the core and cladding.

An arrayed X-ray source rather than traditional X-ray tube with absorption mask was proposed to generate structured light, based on the analysis of grating absorption efficiency and the coherence of X-ray source. According to the intensity distribution of interferogram, the influence of absorption efficiency on visibility of interference fringes was presented. With respect to the state of art micro-fabrication, it was impossible to realize the absorption grating required. The optimal structure of arrayed source was given from the analysis of spatial coherence. In order to verify the feasibility of the method, an arrayed X-ray tube was fabricated and relative measurement was performed.

The influence of filtering characteristics of lossy series coupled two-microring resonators was studied.When the coupling coefficients between the two rings were fixed,under the perfect coupling condition,the influence of the loss on transmittance of the main resonance peak,bandwidth,shape factor and peak transmittance of the spurious modes were analyzed.The effects of the loss on these filtering characteristics were demonstrated.Analysis shows that the transmittance of the spurious modes and the main resonance peak decrease with the optical loss,the coupling coefficients between the two rings and the straight waveguides become smaller,and the bandwidth and the shape factor of the main resonance peak change little.The coupling coefficients between the rings and the straight waveguides should not be too big or small.

A novel high sensitivity fiber optic bending sensor based on Michelson interferometry was developed. The sensing probe utilizes a fiber ribbon affixed onto an elastic structure to generate interference signals as a function of curvature. Further a micro-cavity filled with refractive index matching liquid was added to the optical path length and modulated in audio frequency to modify interference signal, which was demodulated using phase generated signal carrier technology to obtain a highly sensitive detection of curvature change. Experimental measurement of prototype shows that the fiber optic bending sensor can achieve a sensitivity of 43.96 rad/m－1 and a high resolution of 0.004 m－1.

To the methane gas with the concentration lower than 0.5%VOL,an optical methane gas sensor was designed based on near infrared tunable diode laser absorption spectroscopy.The methane gas absorption spectroscopy of 1 653.72 nm was scanned by tunable laser,and the gas concentration was measured by using the first harmonic PAPR.The proposed can effectively eliminate the influences caused by light intensity fluctuation of the laser and other kindred light power fluctuations,and the test results show that the precision of this kind of sensor can be 0.02%VOL.

In order to find out different material evidences in criminal spot, multi-band lamp house was adopted to achieve all kinds of field traces. Multi-band lamp house system can utilize interference cut-off filters of different performances to output different wave-band beams. In order to find body fluids on clothes and other traces, the high transmittance rectangular wave between 450~520 nm waveband with low-cost and high-quality was prepared through the interference filter combination method. The electronic beam depositing method with the aid of ion deposition system was also adopted based on the interference filter theory and film design software during the preparation. It is demanded that transmissivity in pass wave is more than 99%, the other wave-band is less than 0.2%, and its slope is less than 3%.

A physical model was proposed to illustrate the influence of metal film thickness on electrical mean free path, and the formula of electrical mean free path was modified based on this model. The results demonstrate that the electrical mean free path decreases with film thickness decreasing, when the film thickness is less than the mean free path. Otherwise it is a constant as bulk material. The film conductivity expression was also modified based on this formula. Combining with the relationship between metal films′ conductivity and reflectivity, the formula of thin film conductivity with different thickness was put forward. Computer simulations show that when the film thickness is less than the electrical mean free path, the changes of metal film reflectivity are nonlinear.

In order to control the propagation of high power laser beam and make the laser beam focus at any position without quality degradation,the change of high-power laser focal positions was investigated.The proposed research was based on the theory of lens-focusing and laser self-focusing in nonlinear media.Influences of different kinds of factors on the focal position were analyzed.Through numerical solution of the nonlinear Schrdinger equation,the relationships of the focal position with input power,initial waist and focal length of lens were obtained,and thus the method to control the beam focal position was found.The numerical simulations coincide with the theoretical analysis.

According to the dynamic model of Vertical Cavity Surface Emitting Laser(VCSEL) with delay optical feedback，its chaotic dynamic behaviors were discussed by numerical simulation.And the influence of the external cavity length and optical feedback strength on the dynamic was analyzed.The results show that laser with short external cavity will come back to frequency-locked state after chaos.Laser with long external cavity will come back to period 1 instead of the locked state after chaos.When the external cavity is 3.0 cm，with optical feedback strength increasing，laser turns into chaos by bifurcation，and it can also get period 12 window in chaos.The research results have some theoretical reference value on practical applications.

In the research of mouse traumatic brain edema, the near infrared spectroscopy effective detection depth is not clear. Aiming at that problem, Monte Carlo method was used to simulate the photon distribution in biological tissue. The photon′s effective detection depth was calculated from the photon distribution. The multi-layer model of mouse brain was obtained by the segmentation of MRI. The advanced value segmentation, narrowband level set were used to segment the scalp, the skull, cerebrospinal fluid, gray and white matter from the whole brain MRI. This segmentation method does not depend on templates. The tMCimg software, which is used to simulate the photons′ optical distribution in complex tissues, was modified to record the photons′ position and the photons′ energy used in the calculation of the effective detection depth. The effective detection depth was discussed with the different center distance of source and detector and radius of source. Effective detection depth in tissue is less than or equal to half of the distance source and detector and it increases with the radius of the source. The mouse brain edema model was built to verify the simulation. The result is important to the design of source and detector probe and the detection of the edema region.

In order to evaluate drought resistance of wheat seed during germination using bio-photonic technology, treatment to germinating wheat seeds with polyethylene glycol,spontaneous luminescence and delayed luminescence of wheat seed in ultra-weak photon emission during germination under osmotic stress were measured. Through establishment of dynamic equation of delayed luminescence and mathematical fitting, the initial intensity I(0), attenuation parameters β, coherence time τ and integral intensity I (T) of delayed luminescence during germination were obtained. And the state parameters and the order parameter of cell system were constructed according to the significance of delayed luminescence integral intensity and spontaneous luminescence. The expermental results shows that the increases of spontaneous luminescence and integrated intensity of delayed luminescence in ultra-weak photon emission of wheat seed are the stage during germination, the increases of the state parameter and order parameter of cell are the stage, and osmotic stress inhibits these increases. It is suggested that the state parameter and order parameter of cell based on ultra-weak photon emission may be used as physical indicators to evaluate drought resistance of wheat seed during germination.

The infrared radiation characteristics of the plume of stealth aircraft are the key radiation resource for stealth aircraft detection. A new model was presented to calculate the infrared radiation of a stealth aircraft. Based on the model of the normal aircraft, the new model introduced the infrared radiation suppression module to describe the effect of infrared suppression technology. In order to test the feasibility of the model, for the lake of data, the new model was applied to calculate the infrared radiation of plume of the normal aircraft and stealth aircraft. The new model considered the impact of the 2D-nozzle plume, ejection, infrared obscure cloud and blocking on plume radiation of stealth aircraft. The calculation results show that plume radiation add stealth measures is the 5.8% of not added. Compared the calculation results with the reference results and tested spectrum data of the combustion of the aviation kerosene, it was found that the magnitude change in radiation energy is the same as the references, so the new model can be used for calculating infrared radiation of the plume of stealth aircraft.

Considering the practical application of target recognition with optoelectronic joint transform correlator, the infrared image detected was processed by multiwavelet transform, and its edge points were extracted by the method of local modulus maximum. Capturing much contour can improve the capacity of target recognition. The multiwavelet functions usually used to infrared target processing are GHM and SA4. Simulation experiments show that the correlation output of edges extracted by GHM is obviously better than that one of edges extracted by SA4, because the former edges carry much contour of image. Compared to the optical correlation detection result of original image with that of edge image extracted by GHM, it is found that the latter effectively enhances the intensity of correlation peaks.

The effect of system parameters on the reconstructed image quality in in-line digital holographic microscopy was studied. Firstly the spatial frequency of object wave was computed. Under the assumption of perfect imaging, the spatial frequency of object wave in the image space was completely determined by the frequency of the surface structure of the measured specimen and the magnification of the imaging system. Then, a suitable magnification must be designed so that the spatial frequency of object wave in the image space could satisfy the sampling capacity, based on the analysis that all the spatial frequency components of object wave should arrive at the recording plane and be effectively recorded in order to acquire the reconstructed image with high quality. And the recording distance affects on the object size which can be effectively recorded. When the magnification was the same, the size became larger with the decrease of the recording distance. Both the simulation and optical experiments validate the correctness of the proposed analysis.

Through introducing the new application of a genuinely entangled six-qubit state, quantum information splitting of an arbitrary two-qubit state was investigated. For the quantum information splitting, a genuinely entangled six-qubit state was shared by a sender (Alice), a controller (Charlie) and a receiver (Bob). The sender firstly performed twice Bell-state measurements, and then the controller made a Bell-state measurement. Finally the receiver can reconstruct the arbitrary two-qubit state by performing some appropriate unitary transformations on his qubits after he knew the measured results of both the sender and the controller. This quantum information splitting scheme is deterministic, i.e. the probability of success is 100%. In comparison with the quantum information splitting scheme using the same quantum channel the sender and the controller only need to perform Bell-state measurements, not joint multi-qubit measurement, which makes this scheme simpler and easier, and can be fulfilled based on present experimental technology.

Aiming to infrared and visible image fusion effect evaluating question, an assessment method bonding structural similarity and region of interest was proposed based on structural similarity assessment method and human visual characteristics. The method divided region of interest and residual region from infrared and visible image respectively based on different image-forming feature,which indicate the different image characteristics. Then the different weight coefficients were endowed to different image regions based on the visual sensitive level. Compared with the prevenient evaluating method, the proposed method needs no standard reference image participation and upgrades the weight value of image important characteristics in assessment result. Experiment results indicate that the proposed methods is more consistent with subjective evaluation results.

A dictionary training algorithm was proposed for spare representation of images and its convergence was proved.The geometrical explanation of the algorithm is to approximate the hyperspherical cap with least hyperplanes.The algorithm clustered the error vectors of each step,and signed the cluster center as new atoms which made the dictionary more suitable for spare representation of samples.Compared with the traditional algorithm,the new one has higher adaptability,lower requirement of sample number and dictionary size,higher convergence rate,and lower complexity.Finally,the experiment of compressive sensing and denoising demonstrates that dictionary training by this algorithm has good effect.

The geometrical structures,relative stabilities,electronic structures and bonding properties of AlB+n(n = 2~10) clusters have been investigated by using the density functional theory at the level B3LYP/6-311G(d).With the most stable structures obtained,it shows that the boron atoms are more likely to get together,remaining the Al atom lying around the boron-atom group.Compared to the neutral clusters,the effect of Al-B bonds becomes weaker,which leading to a relative bigger change of geometry to neutral clusters when n=2~4 and n=7~10.Via calculating the energy gap for both positive charged and neutral clusters,we found that the stability of AlBn+ (n = 2~10) clusters enhances,especially for AlB+3,AlB+5 and AlB+8 clusters.Infrared vibration spectra of the most stable structures are also investigated.The vibration mode with symmetrical or no-symmetrical vibration between B atoms and fixed Al atom are easier to perform a more intense spectral peak.This result indicates that the B atoms should be preferential to bond.