An algorithm for retrieving polluted coastal aerosol optical properties based on moderate resolution imaging spectrometer (MODIS) data is proposed. New aerosol modes are created based on the characteristics of coastal aerosols; the limitation of computing apparent reflectance in MODIS algorithm is removed; and by selecting infrared spectroscopy bands, water leaving radiance from case II water is reduced. Aerosol robotic network (AERONET) sites data are used to test the proposed algorithm, and the results show that more than two-thirds retrievals lie within the expected error bars. The retrieval meets the requirements of the ocean retrieval accuracy.

A 1.55 μm all-fiber coherent laser demo system for high accuracy velocity measurement is presented. A 1.55 μm fiber laser is used as the transmitter. A fiber optical circulator and a telescope are used as the optical antenna. All optical devices are connected by single mode fiber. The signal and local oscillator (LO) filed are well matched with this system. Fast Fourier transform (FFT) is used to derive the signal Doppler shift. The experimental results indicate that the demo system can measure the target velocity accurately, the relative error of velocity is less than 0.2%. Besides, the problem from LO power intensity noise is discussed. The low-speed Doppler signal detection ability is improved by two orders of magnitude as a result of LO power intensity noise suppressed by pumping current modulation.

Very-narrow-gap bulk-grown HgCdTe single crystals are multicarrier semiconductor system material, since the multiple electrons and holes species frequently contribute to the conduction. Especially for the slight p-type HgCdTe single crystals, the conventional measurements of a single magnetic field can lead to erroneous conclusions because of the large ratio of the electron mobility to hole mobility. The n-type crystals with poor mobility and slight p-type crystals with excellent electrical properties cannot be distinguished by the conventional single-field data. Variable-magnetic-field Hall measurements are performed on bulk-grown HgCdTe single crystals at various temperatures. From the results, the variable-magnetic-field Hall measurements are found to be a suitable tool for differentiation electrical characterization of the two type HgCdTe single crystals. The operating principle of the trapping-mode photoconductive HgCdTe detectors is investigated.

A metal-dielectric-metal grating infrared emission/absorption structure is designed for narrow-band infrared emitters or detectors in application of spectral imaging sensors and biomaterial absorption spectroscopy. By using finite difference time domain (FDTD) method, reflection spectrum of the one dimensional Ag/Si3N4/Ag grating structure is simulated. The results show that very narrow mid-infrared emission/absorption peak is generated in this structure for both TE and TM polarizations and emittance above 98% at the central frequencies can be achieved for both polarizations over a broad emission direction. The origin of this performance is believed to come from the excitation of waveguide mode and surface plasmon mode in this structure.

For detecting laser attacking direction from enemy, we develop a warning system which can detect the direction of coming laser pulse. This system is composed of optical module, signal processing module, and display module. Its detection range is 0° to 360° on the horizontal direction and 0° to 90° on the vertical direction, and angle identification is 30°. Laser pulse wave length of 0.85, 1.06 and 1.54 μm, pulse width no less than 10 ns, can be distinguished. The floor of detection power is 1 mW/cm2, the detection probability is more than 98 percent, and it realizes real-time warning. Compared with former devices, its angle identification is developed, and the floor of detection power is 5～10 km and meets the need of detected distance.

With the help of the unified theory and polarization of partially coherent beams, and the propagation law of the 2×2 cross\|spectral density matrix, the general formula was derived to calculate the degree of polarization for a class of stochastic electromagnetic vortex beam transmitted through a circular ring. Based on these theories, the changes of degree of polarization of the Laguerre\|Gaussian beam and its propagation characterization have been investigated. It is shown that the degree of polarization will change after the beam transmitted through the circular ring, and the degree of polarization of the diffractive beam is related with the coherence, the topological charges of the source, and the size of the circular ring.

The corresponding relation between spatial spectrum and the diamond geometric structure feature is derived by using the optical Fourier transform. An experimental platform for diamond reflected light spatial spectrum detecting analysis system is set up, and the spatial spectrum of a real diamond sample is detected by using this platform. The spatial spectrum of the diamond geometric feature is analyzed, and the characteristics of rotation invariance and translation invariance are discussed.

In the objective quantitative evaluation without ideal image for different image fusion schemes, the vision model of structure similarity index measure metric oversimplifies the characteristic of vision perception and does not consist with monitor properties. We employ new luminance and contrast model and design a new image fusion performance evaluation metric. The experiments prove that the new metric takes more environment influence and monitor properties into account and better compliant with subjective evaluation.

Influenced by gun bore structure and illumination, the gun bore panoramic image has the problem of uneven illumination which will influence the quality of image segment. The de-background is adopted to eliminate the uneven illumination in gun bore images, and the homomorphic filtering based on wavelet is ameliorated through the bayesian shrinkage method. The high-frequency subband images of gun bore panoramic image are revised by weighting, and the low-frequency subband images are modulated linearly. The evaluation criterion for corrections of nonstandard images by different algorithms is proposed. Experimental result of the gun bore panoramic image shows that the modified algorithm can decrease the expense of marginal information, on the basis of improving the image quality primely.

Using white diffuser to calibrate the imaging spectrometer has the advantages of easy realization and high calibration accuracy. For calibrating the imaging spectrometer with a white diffuser, the expression of the collected signal electron number of the imaging spectrometer detector elements is deduced to investigate the effects of the distance H of the standard lamp illuminating the white diffuser and the observation angle β of the imaging spectrometer on the accuracy of the imaging spectrometer calibration. The results indicate that bidirection reflectance distribution function (BRDF) has more influence on the observation angle than illuminating distance, whether considering BRDF or not. When H is in the range of 0.5~1.25 m, β is in the range of 0°~30°, and the relative electron number error is almost less than 1% whether considering BRDF or not.

When the light source is with Gaussian shape spectrum, a dispersion media is inserted in the optical path to deduce the light intensity of double-beam interferences, and the analytic expression of the light intensity is obtained. The dependence of interference fringe visibility and visible range on media thickness, media dispersion and spectral line width are analysed. Meanwhile, the relations between phase and light intensity are also investigated. It′s concluded that the white light interference can also be used to measure both the media dispersion and the group refraction index; the formulation of spectral line width with high measurement accuracy can be deduced; the maximal interference fringe visibility does not appear exactly at the maximal light intensity point; an error of a quater of center wavelength is introduced when one objects the 3rd conclusion above. Some of this conclusions are certified with light sources of different spectral line width experimentally.

The speed of rotating mirror must be measured in shooting period precisely in order to obtain the shooting frequency of framing cameras or scanning speed of steak cameras. A high precision digital measurement method based on digital signal processing (DSP) and field programmable gate array (FPGA) is put forward. DSP and FPGA are communicated by high-speed serial peripheral interface (SPI). Time gate for FPGA is preset by DSP according to the change of rotating mirror′s speed. The measured data is transmitted to DSP for disposing after FPGA′s counting and buffering and to computer for showing in real time. It prevents the overflow of the data and improves the range of rotating speed by adopting 32 bit logic unit for FPGA. High-speed DSP improves the process speed of the data and ensures the real time. The design is feasible by the simulated result of the system and the engineering practice. The precision of speed measurement is up to 0.0001%, and the range is from 3 to 3×108 r/min.

The X-ray diffractomer, ultravidet-visible spectrophotometer and fluorescence spectrometer are used to analyze the structure, optical properties and surface defects of the α-quartz crystal before and after 10.6 μm continuous wave CO2 laser irradiation. The results show that the phase structure of the α-quartz crystal sample surface changes. The absorptivity decreases and transmissivity increases. The point defects are removed by 10.6 μm laser irradiation. During the CO2 laser irradiation, α-quartz crystal experiences a process of rapid heating and cooling. High temperature and thermal stress are the main reasons which lead to the changes of crystal structure and optical property.

The overall steering efficiency (OSE) of the liquid crystal optical phased array (LCOPA) is defined as the ratio of the first order diffraction’s intensity and the incident intensity. It is affected by many factors. A numerical analysis model is established to analyze the OSE. The model regards a LCOPA as the combination of a phase grating and an amplitude grating, and thus, model parameters include not only the geometric structural parameters but also the parameters of the phase profile. The general relations between the OSE and three kinds of factors, i.e. steering angles, the parameters of the LCOPA and errors between ideal and practical phase profiles, are studied. Ways to improve the OSE are proposed as well. Results show that increase of steering angles reduces the OSE while raising fill factors and reducing the pixel size can improve the OSE. Proportional spacing pixels are not the optimal distribution for improving the OSE, for which the method of finite-difference time-domain (FDTD) should be used to design the optimal pixel distribution. Reducing the space of two adjacent phase shifters and raising the phase reset value can improve the OSE obviously.

Dissimilar metal joining of steel/aluminum alloy by slab CO2 laser beam welding with filling wire is investigated and the influence of different heat input on the weld formation quality is introduced. The influence of different heat input on microstructure, phase and mechanical properties of joints are analyzed. The experimental results show that microstructure in the joints with higher heat input parameters compared with lower heat input parameters is no longer homogenous, Fe-Al intermetallic phase with the shape of strip and lump can be found in the joints, the thickness of the intermetallics layer increases in the interface of aluminum/steel joints, and the main phase in the melts of joints transforms from FeAl and solid solution of Al in α-Fe to Fe3Al and solid solution of Al in α-Fe. Mechanical properties deteriorate with the increase of the intermetallics layer. Tensile test shows that tensile (or shear) strength with high heat input parameters is 72.9% of that with low heat input parameters.

The more wavelengths can be generated, the more retinopathy can be cured. An equipment which can generate laser in three colours, red, yellow and green is introduced. It can be appled in diverse retinopathyes. There are two all-soild-state lasers in this equipment. It can work with only one wavelength mode. It also can work with three wavelengths mode by means of fibre coupling and optical mixing. The power of the fundamental frequency light is respectively 26 W and 47 W at the wavelengths 1320 nm and 1064 nm. The power of the 660 nm and the 532 nm is respectively 1 W and 1.9 W; and the output power of the fiber is respectively 0.8 W and 1.5 W. The output power of "Y fiber" is 1.6 W after mixing. In distinct situation, this equipment can take the advantage of the red, yellow and green laser.

An omnidirectional staring multi-target tracking and processing system based on infrared fish-eye lens is proposed to satisfy urgent requirements of large-viewing-field infrared multi-target real-time reconnaissance and tracking. Utilizing infrared fisheye lens and 512 pixel×512 pixel PtSi thermal detector modules, the system can detect threat targets with the whole space-domain capacity and the whole time-domain real-time capability. The hardware of the infrared multi-target processing system based on dual-digital signal processor system is designed to implement data processing for multi-target recognition and tracking algorithms. The read-out circuit and the logical block diagram are presented. The multi-target tracking experiment for some motor targets is carried out, and infrared image sequences including targets 1 and 2 are acquired. Theoretical and experimental tracks of the targets are compared, and availability of the system and real-time capability of multi-target tracking are validated.

In order to guarantee quality of service (QoS) of different priority bursts and effectively reduce the burst loss probability (BLP), an optical buffer mechanism based on priority and burst segmentation in optical burst switching (OBS) networks is proposed. It intercalates the fiber delay units to buffer the segmentation part of bursts in the output data channels. When competition occurs, the header of competition burst data packet or the tail of original burst data packet is segmented according to the priority of bursts. The collision-free parts are exchanged or directly processed in reserved output data channel. Segmentation bursts are buffered in the optical buffer. Simulations show that the mechanism can reduce the burst loss probability of entire networks, and the burst loss probability of the high-priority bursts is much less than those of the low-priority bursts. It also can efficiently reduce the delay and the offset time deficit on QoS guarantee. So the scheme can improve the performance of OBS networks.

The temporal coherence and spatial coherence of laser are the bottleneck of the laser display technology. To solve the speckle suppression problem, a speckle suppression method based on micro-opto-electro-mechanical system (MOEMS) scanning mirror technology is proposed. Meanwhile a simple structure of the two-dimensional micro-mirror, which will provide some references for the research of static, small size, low power consumption, high speed and low cost laser speckle suppression methods is proposed.

Quantum dot-cavity coupling systems is investigated by using quantum master equation. In order to illustrate theory mode, we analyze a strong coupling (SC) experiment in quantum dot-microcavity system. After studying, we find that the pump in the coupling system yieds new criteria to achieve SC with a steady state, where the incoherent pump hinders or favors SC. Double-peak structure of cavity-emitted spectrum is not an unequivocal signature of strong coupling, which dependes on the incoherent pump. Research shows that SC often appears in disguise of a single peak and double peak in the weak coupling (WC) emission spectrum which closely relates to the parameter values controlled in the system. The spectral shape of the cavity emission changes from double peak to single broad peak then to narrow single peak again with increasing exciton pumping. The cavity-emitted spectra characterized in double-peak experience transition from the SC to WC when the cavity decay rate is increasing. The effective coupling strength of the quantum dot-cavity detuning system relates with incoherent pump closely.

Influences of solvents on the three-dimensional excitation-emission matrix (3DEEM) fluorescence spectra of phenol in homogeneous and binary solvents have been investigated. The results show that the 3DEEM fluorescence spectra of phenol in aqueous solution mainly have one peak, locating at λex/λem=245~285 nm/270~350 nm. The center of the fluorescence peak is identified at the excitation/emission wavelengths of λex/λem=272 nm/298 nm. The 3DEEM fluorescence spectral characteristics of norma1-hydrogen-bonded phenol-solvent complexes are compared with those of solvated anion. The results also show that the fluorescence of the phenol is quenched in the binary solvent compared with the homogeneous solvents.