This PDF file contains the front matter associated with SPIE Proceedings Volume 9449, including the Title Page, Copyright information, Table of Contents, Authors, Introduction (if any), and Conference Committee listing.

Focused ring patterns are used for many applications like corneal surgery, micro drilling, optical trapping, etc. The generation of focused ring patterns in the earlier reported cases employed many refractive optical components with different functions. As a result the optics configurations of the ring pattern generation systems are bulkier. In diffractive optics, it is possible to alter a function of an element and also integrate multiple functions in a single element. In this paper, we present the design, fabrication and evaluation of single and composite diffractive optical elements for the generation of focused ring patterns. A diffractive toric Fresnel zone lens was designed for parallel beam illumination. This element is compared with other composite diffractive elements capable of generating focused ring patterns. The toric Fresnel zone lens and composite elements were fabricated using electron beam direct writing. The fabricated elements were found to exhibit interesting properties, with the toric lens out-performing the other elements in several areas such as efficiency, focal depth, and ring thickness.

Multicore structures based on increased index waveguiding traces are fabricated by ultrafast laser photo inscription in bulk optical glass. A parametric study of the geometry of structure, number of traces and index contrast is discussed with respect to guided modes characteristics. Multicore waveguide present optical designs allowing large mode area light guiding by ultrafast laser photo inscription with coherent mode superposition in near infrared and mid-infrared in fused silica and Chalcogenide glass.

In this paper, a high-dimensional statistical signal processing is revisited with the aim of introducing the concept of vector signal representation derived from the Riesz transforms, which are the natural extension and generalization of the one-dimensional Hilbert transform. Under the new concepts of vector correlations proposed recently, the statistical properties of the vector signal representation for random signal are presented and some applications to speckle metrology developed recently are reviewed to demonstrate the unique capability of Riesz transforms.

A phase unwrapping algorithm specially designed for phase-shifting fringe projection profilometry (FPP) is proposed. This algorithm is based on a principle that combines a refined double-frequency fringe projection algorithm and a fringe background based quality guided phase unwrapping algorithm (QGPUA). The phase demodulated from high-frequency fringe images are partially unwrapped by that from the low-frequency ones. This would help to avoid phase order ambiguity in the eventual phase unwrapping while guarantee the phase resolution. The fringe background based QGPUA is adopted to completely unwrap the partially unwrapped phase. The quality map utilized during the phase unwrapping is generated from the fringe background and divided into different subregions. Further unwrapping for the partially unwrapped phase goes on in the order from phase in the highest quality subregion to that in the lowest one gradually. Partially unwrapped phase in each subregion is unwrapped with flood-fill algorithm. Therefore the phase unwrapping speed can be improved. The proposed method can make the phase unwrapping for phase-shifting FPP more robust and faster. Experiment result confirms the effectiveness of the proposed method.

Detecting angle between target and optical axis in Q-APD is an effective way of fast ATP. It is the key point in this method to acquire the ratio of some parameters. In this paper, a novel method of achieving division of analog electric signal using integral chopper is proposed. This can avoid the problem of high speed acquisition faced in the digital processing solution, that is, MHz level sampling frequency should be used in microsecond level signal. After the target is detected by using Q-APD, the four-channel signals generated by target are amplified by the emitter follower. Then using sample hold and sum difference calculation, background signal and offset signals in azimuth and elevation are generated. Because of using the integral chopper, integration time of offset signal to capacitance is controlled by the background signal, and the output value is just the ratio of the background signal and the offset signal. This value which has is independent of intensity of incident light, represents the angle between the target and optical axis. The optical axis can be driven by servo system based on the angle, therefore realizing the fast ATP.

Diamagnetic levitation system is studied in detail in this paper. From top to bottom, the diamagnetic levitation system is composed of a lifting magnet, a top pyrolytic graphite sheet, a floating magnet and a bottom pyrolytic graphite sheet. The gravity of the floating magnet is balanced by the attractive force between the lifting magnet and the floating magnet. And the floating magnet is stably levitated between the top and bottom graphite sheets due to their diamagnetism. The force exerted on the floating magnet is analyzed through theoretical and numerical methods, and at the same time the equilibrium position is obtained. Totally 11 groups of magnets are studied by COMSOL, in which the accumulative error is eliminated to improve the accuracy of finite element analysis(FEA). Corresponding experiments are carried out to verify the numerical results, and the error of equilibrium position is less than 10%, which shows that the FEA is precise enough to simulate the diamagnetic system. Motion characteristic is studied for group 6, in which the lifting magnet is a φ3/16”× 1/8” cylinder. For the floating magnet, the horizontal force versus the eccentric displacement and the vertical force versus the vertical displacement are calculated by COMSOL respectively. In the magnetic potential well of the lifting magnet, the floating magnet returns to the vertical central axis automatically, and the frequencies of the vertical and horizontal movements are between 4 and 5 Hz. The frequencies of the two directional movements can be tuned by the magnetic parameters of the lifting and floating magnets and the structure dimensions of the system. The method used to analyze the diamagnetic system is proved effective to design the diamagnetic levitation structure. Because of the contactless levitation of the floating magnet based on diamagnetism, the system is sensitive to very small input. This diamagnetic levitation structure is potential in micro-actuators and sensors.

Infrared imaging fault detection which is treated as an ideal, non-contact, non-destructive testing method is applied to the circuit board fault detection. Since Infrared images obtained by handheld infrared camera with wide-angle lens have both rigid and non-rigid deformations. To solve this problem, a new demons algorithm based on regional information entropy was proposed. The new method overcame the shortcomings of traditional demons algorithm that was sensitive to the intensity. First, the information entropy image was gotten by computing regional information entropy of the image. Then, the deformation between the two images was calculated that was the same as demons algorithm. Experimental results demonstrated that the proposed algorithm has better robustness in intensity inconsistent images registration compared with the traditional demons algorithm. Achieving accurate registration between intensity inconsistent infrared images provided strong support for the temperature contrast.

We propose a new concept for an unconventional type of two-color method for interferometry-based length measurements based on the adjacent pulse repetition interval length (APRIL), which is the physical length associated with the pulse repetition period. We demonstrate by numerical simulations that if the wavelength-based two-color method can eliminate the inhomogeneous disturbance of effects caused by the phase refractive index, then the APRIL-based two-color method can eliminate the air turbulence of errors induced by the group refractive index. We show that our analysis will benefit the pulse-laser-based two-color method, which secures traceability to the definition of the meter.

CO₂ is the greenhouse gas that influenced by human activities most and has a great impact on the climate change. Monitoring of global CO₂ variations on a basis of, high precision has great significance for the study of global climate change and carbon cycle, as well as the understanding of CO₂ sources and sinks. This study develops the forward model and inversion software system GF_VRTM-V1.0 for space-borne near-infrared hyperspectral measurements of CO₂ into a ground-based observation version. The simulation results are compared with the ground-based data of the column-averaged mole fraction of carbon dioxide measured at Fuling, and showed general agreement.

Observations are presented of the Volume scattering function (VSF) over the angular interval 20 to 160°, to maximum depth of about 90m in the Northern South China Sea in Case I and Case II waters. The observations were collected by using a self-developed in situ scattering instrument, which synchronously measured the attenuation coefficient, the VSFs in seven angles between 20 to 160° at 650nm, and the sea depths. General, the VSFs show a strong scattering in the forward, a broad scattering minimum in the scattering angular interval 90 to 126° and a weak increase in the rest of backward scattering angles. The analysis of the in situ data also indicates that the magnitude and the shape of the VSF change with areas and profile depths. From Case II to Case I, the forward scattering in 20°, which is mainly due to relatively large suspended particles, varied about three orders magnitude with highest values observed in Case II waters. In Case I waters, form the surface layer to the deeper layer, the magnitude of the VSFs firstly decreased with the depth, and then increased with the depth until reached a maximum scattering layer between 30 to 50m, and then decreased with depth until reached the maximum measurement depth. In Case II waters, the vertical profile distributions of VSF are complex, but in almost all profile, the magnitude of the VSFs firstly decreased with the depth, and then increased with the depth until reached the maximum measurement depth.

The result of analysis also showed that in almost all of these stations, in the surface water, based on the light scattering by bubbles at shallow depths, the angle scattering at 60º-80º has a significant “shoulder”, and the wind plays a key role in the bubble scattering.

In order to enhance the capability of space-based surveillance, the detailed non-resolved space object characterization with brightness data is described in this paper. Firstly, according to the optical scattering theory, mathematical model for brightness characteristics of space object is established with the bidirectional reflectance distribution function (BRDF) by region classification and grid division. Then, brightness of typical geosynchronous satellites is simulated. Influences of the shape, size and status on brightness are analyzed. Characterization with brightness data is proposed. It shows the shape, size and status of the object can be deduced with brightness data over a range of time-space periods. Finally, the several special fields of non-resolved space object characterization are discussed

The unresonant procedure of the interaction of atoms with cavity-field by intensity-dependent coupling was analyzed in the union system consisting of multi-atom and multi-cavity using of the complete quantum theory. The results show that through controlling the time of cavity-field interacting with atoms and measuring the atomic states just being out of cavity, the quantum entangled information can be completely exchange between the atomic maximal entangled state and the maximal like-odd-even coherent entangled state. The quantum information can be completely swapping transmit on account of properly confining the detuning value. The process above mentioned display that the evolution is opposite each other in the close system.

The development decoding algorithms of two-dimensional cross strip anodes image readouts for applications in UV astronomy are described. We present results with Monte Carlo simulation by GEANT4 toolkit, the results show that when the cross strip anode period is 0.5mm and the electrode width is 0.4mm, the spatial resolution accuracy is sufficient to reach better than 5 μm, the temporal resolution accuracy of the event detection can be as low as 100 ps. The influences of the cross strip detector parameters, such as the anode period, the width of anode fingers (electrode), the width of the charge footprint at the anode (determined by the distance and the field between the MCP and the anode), the gain of the MCP and equivalent noise charge (ENC) are also discussed. The development decoding algorithms and simulation results can be useful for the designing and performance improvement of future photon counting imaging detectors for UV Astronomy.

An ordinary space optical remote sensing camera is an optical diffraction-limited system and a low-pass filter from the theory of Fourier Optics, and all the digital imaging sensors, whether the CCD or CMOS, are low-pass filters as well. Therefore, when the optical image with abundant high-frequency components passes through an optical imaging system, the profuse middle-frequency information is attenuated and the rich high-frequency information is lost, which will blur the remote sensing image. In order to overcome this shortcoming of the space optical remote sensing camera, an online compensating approach of the Modulation Transfer Function in the space cameras is designed. The designed method was realized by a hardware analog circuit placed before the A/D converter, which was composed of adjustable low-pass filters with a calculated value of quality factor Q. Through the adjustment of the quality factor Q of the filters, the MTF of the processed image is compensated. The experiment results display that the realized compensating circuit in a space optical camera is capable of improving the MTF of an optical remote sensing imaging system 30% higher than that of no compensation. This quantized principle can efficiently instruct the MTF compensating circuit design in practice.

A method is presented for generating multiple-channel color-entangled photon pairs simultaneously based on type I quasi-phase-matched spontaneous parametric downconversion pumped in a single periodically poled lithium niobate (PPLN) crystal. It is predicted that one-, and two-channel color-entangled photon pairs can be simultaneously generated just by suitably choosing the PPLN grating period and the pump frequency. We point out that the full width at half maximum (FWHM) of idler and signal light are broadened dramatically due to spontaneous parametric downconversion in case of a pulsed pump. Then this method is applied for generating multiple-channel polarization-entangled photon pairs simultaneously based on type II quasiphase- matched spontaneous parametric downconversion.

The spectra of O2 A-band (0.76 μm) and CO2 near-infrared emissions (1.6 μm) for Medium-resolution Satellite (SCIAMACHY) are simulated by the SCIATRAN model (V3.1.29), and compared with the ESFT and LBL method, as the inversion accuracy and time consuming. The time consuming of LBL was more than ESFT with the relative error less than 1%, especially for the CO₂ band. But for the CO₂ (2.0 um) of High-resolution Satellite, the opposite result was found. That is to say, the LBL method was more suitable for High-resolution Satellite. Different wavelength intervals and integral wavelength steps are applied to the LBL to select the most appropriate combination for High-resolution SatelliteO₂ A-band (0.76 μm) and CO₂ near-infrared band (1.58 μm).

It is important for particle detection technology to research the polarization properties of particle’s scattered light and explore the relationship between particle size and polarization degree of its scattered light. Particle scattering model was established and polarization properties of spherical particle’s scattered light with different sizes and different scattering angles was simulated using the finite element method. The polarization degree of particle scattered light were explored with different sizes, also were the polarization degree with different scattering angles. Results show that relationship curves between polarization degree and scattering angles can be described as parabolas. Polarization degree increases when scattering angles increase in the range of 0°-90° and reached the maximum value at 90°. Polarization degree decreases when the size of particle increase and this change more obvious gradually. The polarization degree of particle scattered light reached 1 at 90°when the particle size is much smaller than the wavelength and the maximum value of polarization degree decreases gradually when particle size increase further. In order to verify the correctness of the finite element simulation model, the polarization degrees were calculated in different particle sizes and different scattering angles by classical Mie scattering theory. Polarization simulation model of particle scattered light is proved to be correct and effective by making comparisons between simulation results and theoretical calculation results. This model lays a foundation for the further research on polarization characteristics of particle scattered light with different morphology and distribution.

In order to improve high-speed laser space optical communications terminal receive energy and emission energy, meet the demand of mini-type and light-type for space-based bear platform, based on multiple-reflect coaxial optical receiving antenna structure, while considering the installation difficulty, a high-efficient optical system had been designed, which aperture is off-axial, both signal-receiving sub-optical system and emission sub-optical system share a same primary optical path. By the separating light lens behind the primary optical path, the received light with little energy will be filtered and shaped and then transmitted to each detector, at the same time, by the coupling element, the high-power laser will be coupling into optical antenna, and then emitted to outside. Applied the power-detected optical system evaluate principle, the optimized off-axial optical system's efficiency had been compared with the coaxial optical system. While, analyzed the Gauss beam energy distribution by numerical theory, discussed that whether off-axis optical system can be an emission terminal, verify the feasibility of the theory of the design of the system.

We introduced a generalized version of the transport of intensity equation from a partially coherent phase-space perspective that relates axial intensity derivative to the transverse divergence of the conditional frequency moment of the Wigner distribution function. This expression provides a powerful analytical tool for the study of phase retrieval and computational imaging under partially coherent illuminations. The correspondence between the Wigner distribution function and the light field in the geometric optics enables extracting phase information from the light field and vice versa for slowly varying specimen under certain simplified illumination conditions.

It has been a debatable problem that what the essence of light is, and how it is produced. Since the modern times, as James Clerk Maxwell setting the theory of electromagnetic up, the mainstream consciousness was occupied gradually by the wave theory of light. But at the end of 19th century, a series experimental phenomenon weren't precisely explained by the wave theory of light such as photoelectric effect experiment. Then Albert Einstein published his famous paper “On a Heuristic Viewpoint Concerning the Production and Transformation of Light”, which laid the foundation of light quantum hypothesis. While solving these problems perfectly, a new problem was caused that because the wave theory and the quantum theory are both applicable to interpret some of the experiment of light, what is the essence of light. This paper first outlines the history of optical development and current status, and states the difficulties and deficiencies of the study of light. Then we put forward the key concept of the paper called lightstring which consults some points of the theory of modern optics and physics which called the optical frequency comb and the string theory, then presents the essence of light based on the light string concept in order to make the concept of photons specific. And then we put forward the production mechanism of light ---- the String-Light effect based on the concept of light string. In this paper, we attempt to put forward a new idea of the study of the essence of light and the production mechanism of it.

The number of perspective views limits the viewing zone of a passive, untracked autostereoscopic display. To enhance the freedom of movement in front of the 3D display, the number of views has to increase as well. An improvement of the viewing zone caused by the raising view numbers will result in lower resolution of each single perspective. A few companies have showed 3D displays with more than 8 or 9 views (including Sunny Ocean Studios 64 view display).

The number of effective orthoscopic stereo image pairs is a triangular number on the base of the perspective views n. Using a stereoscopic glass (with only 2 views), the triangular number nΔ is also 2. But in a 5 view display (i.e. techXpert 3D display), nΔ=10. In a theoretical case, each vertical line of a display, represented by a sub-pixel, could consist a single view. On a real display with 7.680 sub pixel columns, the resulting triangular number is more than 29 million.

The display system guides more than one view in the pupil of the observer’s eye. This superposition principle of views leads to a reduction of channel separation and an increase of cross talk.

It will be examined if a multitude of very low-resolution images with a high crosstalk could reproduce a satisfying 3D image.

A thermal effect model is presented in this paper, with the background of ground-based laser irradiating moving and rotating target in the air. Firstly, the encounter scene of laser irradiating target is assumed, and the main parameters of laser and target are given. Secondly, the calculation model of irradiating parameters is derived, including irradiating area, power density distribution and convection heat transfer per unit area. Thirdly, the thermal effect model is established to describe heat conduction and thermal ablation during laser irradiating. Finally, the thermal effects are calculated by assuming the parameters in encounter scene of laser irradiating target. As shown in the example, the thermal effect model can minutely describe the temperature field and ablation results of moving and rotating target irradiated by laser.

Digital holography (DH) is a 3D imaging technique with a theoretical axial accuracy of better than 1-2 nanome-ters. However, practically, the axial error has been quoted to be tens of nanometers which is much larger than the theoretical value. Previous studies of the axial error mainly focused on the phase error introduced by lens. However, it is found that CCD aperture size is also an important contributors to axial error by our group. It is necessary to investigate the reduction approach of such axial error. The most possible connection between the limited CCD aperture size and the axial error is the diffraction effect. Window functions once have been applied to digital holograms for diffraction suppression and improve the lateral resolution of the intensity image. How-ever, their impacts on phase image and the associated axial dimension measurement are still unknown. In this paper, window functions are applied to digital holograms for phase/axial error reduction. Both simulation and experiment are performed. Moreover, the relation between axial error and window functions is also illustrated by the mathematical formulas derived in the theory. And all the results validate that the window functions can reduce the axial error of digital holography.

Infrared character of aircraft is one important factor to estimate the ability of breaching the defense of enemy, this paper firstly analyzed the method of infrared calibration with collimator and energy factors composing the sky background, propose one method of deleting energy of background within current image; furthermore, the paper points out that the parameters of calibration with collimator can’t be directly applied to computing Infrared character of flying target, and based on that propose the method of deleting energy of background with another background image measured before mission.

A single-channel color image encryption method is proposed based on iterative phase iterative process in quaternion Fourier transform domain. First, three components of the plain color image is confused respectively by using cat map. Second, the confused components are combined into a pure quaternion image, which is encode to the phase only function by using an iterative phase retrieval process. Finally, the phase only function is encrypted into the gray scale ciphertext with stationary white noise distribution based on the chaotic diffusion, which has camouflage property to some extent. The corresponding plain color image can be recovered from the ciphertext only with correct keys in the decryption process. Simulation results verify the feasibility and effectiveness of the proposed method.

Known disparity search range is a crucial parameter for many stereo matching algorithms. It is necessary to estimate the disparity search range automatically in real time systems. In this work, we present an approach to estimate disparity search range of each pixel to be matched. A dual-mode camera which can be used to take stereo images or coarse depth maps is developed in our work. Under the constraint of the coarse depth map with the same spatial resolution as the stereo pairs, expected disparity of each pixel is limited within a narrow search range. We demonstrate the effectiveness of the proposed approach on benchmark images with ground truth as well as on images captured in our lab.

Two wavelength optical signals in the infrared regime were generated in atomic rubidium (Rb) vapor using a Ti:sapphire laser amplifier and competition between the two signals was observed. The effects of Rb number density, pump laser intensity and the chirp of laser pulses on the characteristics of the two signals were investigated. The results show that the two signals were mainly generated by two coupled difference frequency six wave mixings and, in the meantime, two coupled six wave mixing channels were identified. The competition between the two signals is dominantly governed by phase matching conditions in the two six wave mixing processes. The phase matching conditions in the two channels are primarily determined by the Rb number density and, whereas, the phase matching conditions are scarcely related to pump laser intensity and the chirp of pump laser pulses.

Cabbage growth and health diagnosis are important parts for cabbage fine planting, spectral imaging technology with the advantages of obtaining spectrum and space information of the target at the same time, which has become a research hotspot at home and abroad. The experiment measures the reflection spectrum at different stages using liquid crystal tunable filter (LCTF) and monochromatic CMOS camera composed of spectral imaging system for cabbage leaves damaged by diamondback moth pests, and analyzes its feature bands and the change of spectral parameters. The study shows that the feature bands of cabbage leaves damaged by diamondback moth pests have a tendency to blue light direction, the red edge towards blue shift, and red valley raising in spectral characteristic parameters, which have a good indication in diagnosing the extent of cabbage damaged by pests. Therefore, it has a unique advantage of monitoring the cabbage leaves damaged by diamondback moth pests by combinating feature bands and spectral characteristic parameters in spectral imaging technology.

In this paper, absolute spectral responsivity and relative spectral responsivity of silicon trap detectors are presented. The absolute spectral responsivity calibrated with absolute cryogenic radiometer at seven wavelengths between 488nm and 1064nm. The absolute spectral responsivity scale is obtained in the spectral range from 400nm to 1100nm. The external quantum efficiency of the silicon trap detector is investigated.

The paper presents a hardware in loop dynamic IR scene simulation technology for IR hyperspectral imaging system. Along with fleetly development of new type EO detecting, remote sensing and hyperspectral imaging technique, not only static parameters’ calibration of hyperspectral IR imaging system but also dynamic parameters’ testing and evaluation are required, thus hyperspectral dynamic IR simulation and evaluation become more and more important. Hyperspectral dynamic IR scene projector utilizes hyperspectral space and time domain features controlling spectrum and time synchronously to realize hardware in loop simulation. Hyperspectral IR target and background simulating image can be gained by the accomplishment of 3D model and IR characteristic romancing, hyperspectral dynamic IR scene is produced by image converting device. The main parameters of a developed hyperspectral dynamic IR scene projector: wave band range is 3~5μm, 8~12μm; Field of View (FOV) is 8°; spatial resolution is 1024×768; spectrum resolution is 1%~2%. IR source and simulating scene features should be consistent with spectrum characters of target, and different spectrum channel’s images can be gotten from calibration. A hyperspectral imaging system splits light with dispersing type grating, pushbrooms and collects the output signal of dynamic IR scene projector. With hyperspectral scene spectrum modeling, IR features romancing, atmosphere transmission feature modeling and IR scene projecting, target and scene in outfield can be simulated ideally, simulation and evaluation of IR hyperspectral imaging system’s dynamic features are accomplished in laboratory.

Raman spectrometry was employed to study the characteristics of Raman spectra of aliphatic polyamide fiber and polyethylene terephthalate (PET), which were treated with sodium hydroxide, sulfuric acid and copper sulfate, respectively. Raman spectra under different conditions were obtained and the characteristics of the Raman spectra were analyzed. The results show that Raman peaks beyond 1200 cm^-1 appear for aliphatic polyamide fiber processed by sodium hydroxide, while the Raman peaks beyond 1000 cm^-1 disappear for aliphatic polyamide fiber processed by sulfuric acid. Raman peaks beyond 1750 cm^-1 decrease for polyethylene terephthalate processed by sodium hydroxide, while Raman peaks beyond 1000 cm^-1 disappear, except weak peaks around 3000 cm^-1 , for polyethylene terephthalate processed by sulfuric acid. The variations of the Raman spectra are primarily related to the changes of chemical bonds and molecular structures.

Temporally and Spatially Modulated Fourier Transform Imaging Spectrometer (TSMFTIS) is a new imaging spectrometer without moving mirrors and slits. The interferogram of the target point can be consisted by sequentially arranging the interference information extracted from the same target point of the sequential images, and the spectrum can be recovered by using fast Fourier transform. In the practical application, there is nonuniform sampling in the interference data, and many researchers have carried out researches on nonuniform sampling with the fast Fourier transform algorithm. As to the issue of interference data in the nonuniform sampling, the nonuniform sampling degree’s impact on the recovered spectrum precision is currently and mainly analyzed. This paper has adapted several typical nonuniform fast Fourier transform (NUFFT) methods, carried out spectrum recovery precision comparison on the interferogram of the nonuniform sampling point with the above methods, and further analyzed the impact of kernel function type, oversampling ratio and kernel function width’s on spectrum recovery precision in the above mentioned methods. The experiment result indicates that, when the oversampling ratio is 4 and the kernel function width is 4, the spectrum recovery precision with NUFFT based on Blackman type kernel function is optimal, however, the Gaussian kernel function is stable.

Traditional spectral based color reproduction technologies cannot achieve the faithful reproduction of the object color. There are errors between reconstructed images and original ones. To solve this problem, an error compensation method is researched in this paper after spectral reflectance reconstruction and dimension reduction of spectral data. Experimental data show that the proposed method can significantly improve spectral accuracy, decrease system disturbance and achieve device independent and scene unrelated features.

In this paper, light-emitting diode (LED) based two-dimensional fluorescence correlation spectroscopy was used to discriminate tea leaves with different grades. The distance between LED and tea samples was changed as an external variable. As the fluorescence spectral data collected through the experiment was large, principal component regression (PCR) was used to extract the important information and analyze the spectral data. The final two-dimensional fluorescence correlation spectra contour maps showed obvious difference between different tea leaves and the predictive results based on the leave-one-out method. It showed the strong ability of this spectral method for tea classification.

In this paper, HMME-TiO₂ nanocomposites was synthesized and characterized through TEM， Uv-vis spectra, Zeta potential, FTIR spectra. The characterization results show that HMME was successfully conjugated onto the surface of TiO₂. It can be seen from the TEM images the average size of HMME-TiO₂ conjugation is nearly spherical and the particle size range from 20 to 28 nm. Compared with HMME, the B bands of HMME-TiO₂ were much broader and lower while in the region of Q bands the absorption peaks of HMME-TiO₂ are higher than that of HMME. Encapsulation efficiency of HMME-loaded TiO₂ was assessed and calculated as 45.46%. FTIR spectra show the bonding between TiO₂ and HMME was through the hydrogen-bonding between COOH and OH bonds. Fluorescence microscope results demonstrated HMME-TiO₂ mainly distributed in the membrane and cytoplasm of SCC cells and its best incubation time is six hours. After treated with HMME-TiO₂ plus light irradiation (1.8J/cm² , 632nm), the viability of SCC cells turned to 32.96% is much lower than that treated with HMME plus light irradiation. It can be concluded that the combination of HMME and TiO₂ will enhance the PDT efficiency of HMME. In the process of HMME-TiO₂ mediated PDT, as a kind of photosensitizer HMME can induce the death of SCC cells, meanwhile it can transform electron to the conductive band of TiO₂ stimulating the photocatalytic activity of TiO₂ under visible light. The photocatalytic of TiO₂ can also induce the death of SCC cells. The combination of these two effects lead to more SCC cells died.

Abstract: An instrument was built to measure the output fluorescence response characteristics of a 248nm KrF laser using 4mm-thick fluorescent glass as a screen. Experiments show when irradiated laser intensity is no more than 0.7J/cm^2, the fluorescent response is linear. And the fluorescent spot intensity distribution was spatial coherent with the output beam profile distribution of the LPX-150. So we can use high-homogeneity optical glasses as fluorescence wavelength conversion material in beam profile measurements.

Future space missions may use laser power beaming systems with a high power laser to transmit light to a photovoltaic array receiver. The photovoltaic array receiver can be mounted to a satellite or a spacecraft. To investigate the V-I and P-V characteristics of photovoltaic cells (PV cells) under laser illumination, a mathematical model and simulation model related to the voltage and current of PV cells is studied. Based on the MATLAB simulation tool, the simulated V-I and P-V characteristics of PV cells for various irradiances are presented. To validate the simulated results, three experiments are designed. The results obtained by experimenting are compared with the simulated results, and the difference between them is not apparent.

Infrared-to-visible upconversion emission intensities are investigated in Li⁺/Er³⁺, Li⁺/Ho³⁺/Yb³⁺ and Li⁺/Tm³⁺/Yb³⁺ codoped oxide nanocrystals. By introducing Li⁺ ion, the upconversion emission intensity of rare-earth ions are significantly enhanced comparing with that without the Li⁺ ion. The local structure around Er³⁺ and Ho³⁺ ions are studied by the extended X-ray absorption fine structure spectroscopy. After doping Li⁺ ion, both the average bond lengths of Er-O and Ho-O are decreased.

Total internal reflection diffraction gratings in conical mounting, where the plane of incidence does not contain the grating vector, are investigated in this paper and the relevant conditions and parameters for such gratings are presented. These are then used to design total internal reflection diffraction gratings in conical mounting that the diffraction angle into the first order is equal to the incidence angle. The applications of such gratings in conical mounting to planar optics configurations, which have at least three gratings and one of them is total internal reflection diffraction grating in conical mounting, are discussed in detail. Also, the diffraction properties of all three gratings in this configuration, especially the grating period which is the most important parameter of gratings, are analyzed. The main condition, on which all the gratings in planar display configuration have the same grating periods, is presented based on theoretical analysis: the turning grating should be in 60 deg conical mounting. The configuration can be used to virtual display or wearable display.

The digital calendar circuits controlled by 80C52 have been designed based on Proteus simulation software. The whole design process is made of three parts: hardware circuits, software programming and software simulation. Finally, it shows that the circuit design of hardware and software is correct through Proteus software simulation. The method of circuit design is systematic and practical, which will provide certain design ideas and reference value for display circuit in the future.

A humidity sensor based on microfiber Bragg grating is proposed and demonstrated. The microfiber Bragg grating is obtained through chemical etching commercial fiber Bragg grating. The experimental results show that the central wavelength of the microfiber Bragg grating has red shift with humidity increasing, while the power decreases. The relative humidity sensitivity of the microfiber Bragg grating with diameter of 8.9um is 3pm/%RH in the range of 55%-80%RH. Furthermore, the sensor has a linear response to humidity with linear fitting of 0.991. The sensor possesses advantages of easy fabrication and low cost.

The negative refractive index characteristics of one-dimensional photonic crystal consisted by Fibonacci multi-layer films has been studied by numerical method. The refractive indices for two materials, which are used to construct the Fibonacci multi-layer films, are 0.920 and 0.999, respectively. The calculation result shows that, on one hand, there are several negative refractive index zones for this kind of photonic crystal even if the refractive indices are very small; on the other hand, the difference is very large for the frequency between the zones. As an example, a kind of transmission-type plano-concave lens is designed. The simulation of the electromagnetic field distribution for the lens demonstrates that the lens can focus the incoming X-ray radiation. At the same time, the calculation of the absorption strength and refractive indices for real materials shows that not only there are large differences for the absorption strength with different materials, but also the refractive indices for real materials are different in X-ray band. Obviously, the characteristics above support a kind of transmission-type lens using in X-ray.

We theoretically investigated the ultrafast thermal excitation behaviors on Au films surface irradiated by polarization-shaped femtosecond laser. The spatio-temporal dynamics of temperature evolution in Au film with polarization-shaped femtosecond laser excitation are obtained based on Finite Element Method (FEM). It is revealed that the phonon temperature fields can be flexibly adjusted by optimizing the polarization state combinations of polarization-shaped double femtosecond laser pulses. The results are attributed to pulse synthetic effect, which closely depends on the polarization state combinations of double femtosecond laser pulses. The study provides the basic for understanding of the thermal excitation dynamics for optimizing laser micro and nano-fabrications via tailoring the polarization state of temporally shaped femtosecond laser.

The monolayer SiN_x optical thin films were prepared by Plasma Enhanced Chemical Vapor Deposition (PECVD) technology on the BK7 glass substrate, the laser-induced damage threshold was measured by laser damage testing equipment, and we also investigated the relations between processing techniques and laser-induced damage properties. The study and analysis to orthogonal experiment results show that PECVD processing techniques have an effect on the laser-induced damage properties. Among them,radio frequency has the biggest effection, temperature is the main factor, working pressure is the unimportant factor, and we also achieve the optimal processing parameters (Temperature is 350℃; RF power is 250W; Working pressure is 60Pa).

Ordinary inter-satellite optical includes at least three optical paths for acquisition, tracking and communication, the three optical paths work simultaneously and share the received power. An optimal structure of inter-satellite optical communication terminal with single working optical path at each of working stages of acquisition and communication is introduced. A space optical switch based on frustrated total internal reflection effect is applied to switch the received laser power between the acquisition sensor and the communication sensor between the stages of acquisition and communication, this is named as power fusion which means power is transferred for shutting down unused optical path. For the stages of tracking and communication, a multiple cells sensor is used to accomplish the operation of tracking while communication, this is named as function fusion which means accomplishing multiple functions by one device to reduce the redundant optical paths. For optical communication terminal with single working path structure, the total received laser power would be detected by one sensor for each different stages of acquisition, tracking and communication, the link budget would be maximized, and this design would help to enlarge the system tolerance and reduce the acquisition time.

Surface conduction electron emission device (SED) was fabricated with a back gate electrode. And then the device was electroformed in using continuous triangle wave at vacuum environment. After that we prepare an aluminum back electrode on the back of device. With the back electrode voltage changing, we could observe the change of the emission current. When device voltage and anode are fixed, the device’s emission current and efficiency decrease under positive back voltage of 5V. On the contrary, the device’s emission current and efficiency increase with negative back voltage of -5V. Our results directly proved that the emission electrons were from the field include cool electron emission, but not from the power induced thermal electron emission due to size-effect.

The bit error rate is raised by the presence of the noise when the quantum key transmits in practice. So both sides of communication can not judge the presence of eavesdropping. For this issue, an improved scheme based on BB84 protocol is proposed by a paper of Luanxin that a matrix transformation is carried out for every quantum of both sides. The advantage of the transformation is that the eavesdropper can be found easily. But the disadvantage is that it leads to a low key generation rate. In this paper, an improvement that a matrix transformation is carried out randomly for the quantum of both sides based on the scheme of Luanxin is proposed. The result shows that not only the presence of eavesdropping can be judged easily, but also the key generation rate is increased significantly.

Readout circuit is designed for a special retina-like CMOS image sensor. To realize the pixels timing drive and readout of the sensor, the Altera's Cyclone II FPGA is used as a control chip. The voltage of the sensor is supported by a voltage chip initialized by SPI with AVR MCU system. The analog image signal outputted by the sensor is converted to digital image data by 12-bits A/D converter ADS807 and the digital data is memorized in the SRAM. Using the Camera-link image grabber, the data stored in SRAM is transformed to image shown on PC. Experimental results show the circuit works well on retina-like CMOS timing drive and image readout and images can be displayed properly on the PC.

The complex index of refraction was the fixed characteristic of the target material. In the remote sense field, the complex index of the refraction is a useful parameter for classify and recognize the material. To detect the complex index of the refraction of the opaque material was difficult. A new method of estimating the complex refraction index based on the measured polarization degree of the material according to the different incident angle of reflectance angle was provided. The result showed that the stability and reliability of the acquired complex refraction index was fine.

Imaging laser radar is a new type radar with vast potentials, that it can provide echo intensity image, range gating image, velocity image and three-dimensional image of the target at the same time. In order to improve its performance, to combine the polarization spectral detection technique with the imaging laser radar technique is worth studying. In this paper, the author studies the characteristics of laser echo using the method of modeling, as well as the theories of Stokes parameters and Mueller matrices. In the first place the author derives a polarized bidirectional reflectance distribution function (polarized BRDF) model that simulates the polarimetric of the laser echo from the basic theory with established scalar BRDF models. Then it makes a simulation of all the process of the model construction and compares the results to the experiment data. With the results of comparison it makes corrections of some parameters in the polarized model and obtains a relatively correct polarized model in the end. At last, the author induces the characteristics of laser echo with some main influence factors.

A high average power and high beam quality nanosecond laser is presented that is based on CW diode side-pumped Nd:YVO₄ grazing-incidence slab amplifier. A TEM₀₀, passively Q-switched diode-pumped Nd:YAG laser as the seed laser, generating a M² ≈1.3 beam train of 0.25W, 2.3ns pulses with adjustable repetition rate in the range 5-20kHz. After double-pass amplification, more than 20W of output power with a beam quality of M² ≈1.4 is obtained at an optical-optical efficiency of 35%. The high brightness of this laser system seems ideal for nonlinear optics and laser processing applications.

The color based on prism dispersion was analyzed and the mathematical model was established in this paper. Firstly, based on Dan Bruton's research, the mapping relationship between visible wavelength and data in color map matrix was created, the geometric data of color after dispersion of the prism was processed with least squares curve fitting, then the mapping relationship between wavelength and the refractive index was built. Secondly, on the basis of the work before, the mapping relationship between wavelength and projection geometry was built. Finally, through the building of color management system, the characterization of spectral lines and colors in LAB color space would be got.

Framing camera based on gated Micro-channel plate (MCP) was widely used in inertial confinement fusion (ICF) and Z-pinch because of its ultrafast time-resolve. Electrons with imaging information are multiplied when the HV pulse propagating through the MCP strip line. Obviously, the HV pulse was used as a shutter here, then the exposure time of the imagine will be determined by the width of the pulse. Theoretical analysis indicates that thegating pulse(200ps) has a bandwidth of 5GHz, thus, impedance match in the propagating path of the pulse will be very important. Impedance mismatch will cause reflecting of the pulse and decrease the transmission efficiency. This will cause un-uniformity of the dynamic gain of the MCP, and finally resulting in imagedistortion. A new designed impedance matching circuit is developed in this paper. Simulated results showedthatthe newdesignedimpedance matching circuit couldreduce the reflection of thegating pulse significantly, and dynamicgain uniformity of the MCP was increased simultaneously

Diamond-like carbon (DLC) filmare widely used in the infrared protection window, but their ability of anti-laser damage is insufficient. The common methods to improve the anti-laser ability of DLC films were summarized at first, then a new method which use the external electric field was proposed. Based on the standards ISO11254 of laser damage threshold, the damage morphology of DLC films with and without the bias field were compared. The results show that with the bias field, damage morphologies changes obviously under the same laser energy. According to the physical mechanism analysis, the photogenerated electrons of the films under the action of electric field drift speedy, the drift reduce the heat generated from the laser radiation area, then relayed the graphitization of the DLC films. This after-treated method will be a new method to improve DLC films’ anti-laser damage ability.