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We discussed the influence of weak turbulent seawater on the capacity of underwater optical communication channel. A channel capacity model of shifted and deflected Bessel Gaussian beam links is derived. The results show that the channel capacity decreases as the rate of dissipation of kinetic energy per unit mass of fluid and the inner scale decrease, and it increases as the increase of the dissipation rate of the mean-squared temperature as well as the outer scale. And the channel capacity increases with the increase of the number of channels and the decrease of the angular half-aperture of the cone and shift.

A novel hybrid BOTDR and Φ-OTDR system for simultaneous static and dynamic measurements is proposed. Employing the division of both backscattering light and local light, a double coherent detection configuration is achieved to extend the sensing range and demodulate the phase quantitively. With the independent detection of Brillouin scattering light and Rayleigh scattering light, the demodulation error in BOTDR is avoided while the signal-to-noise ratio of Φ-OTDR is enhanced. Experiment for simultaneously measuring temperature and vibration is carried out, which proves the sensing range of the hybrid system is 49.5km with 20m spatial resolution. The measurement uncertainty of BOTDR is verified to be 2.821MHz, and the maximum frequency response range of Φ-OTDR is 900Hz. Experimental results indicate the proposed system is specialized in dealing with both static and dynamic situations simultaneously.

We develop the channel capacity of atmosphere turbulence links with carrier Bessel-Gaussian vortex localized wave. By this capacity model, we investigate the influences of atmosphere turbulence and carrier parameters on the channel capacity. The results show that as the increase of the refractive index structure constant, channel capacity of links decreases, with the increase of Quantum number M, the channel capacity increase. This work provides a theoretical basis for realizing high capacity atmosphere optical communication with carrier Bessel-Gaussian vortex localized wave.

Consider the evolution of the wander and M2-factor of Mathieu Gaussian-Schell beam in turbulent ocean. We develop models for wander and M2-factor of this beam based the theory of wigner distribution function. The influences of the oceanic parameters on the wander and M2-factor are discussed in detail. It is found that as the propagation distance, the dissipation rate of temperature variance, the eddy diffusivity ratio and ratio of temperature and salinity contributions to the refractive-index spectrum increases, both M2-factor and beam wander increase; but M2-factor and beam wander increase with the decreasing of initial beam width, the kinetic energy per unit mass of fluid. However, as the variation of ellipticity factor and OAM quantum number increase, the evolution of M2-factor and beam wander are some complexes. The influences of coherent width of light source and wavelength on the M2-factor and beam wander are negligible. Our results are helpful in the design of an optical communication system in an oceanic environment.

Based on the power spectrum of the index fluctuation with the outer scale of seawater turbulence, we develop the channel capacity of oceanic turbulence links with carrier Bessel-Gaussian vortex localized wave. By this capacity model, we investigate the influences of seawater turbulence and carrier parameters on the channel capacity. The results show that higher rate of dissipation of kinetic energy per unit mass of fluid, larger inner scale, or lower dissipation rate of the meansquared temperature causes the higher channel capacity; the Bessel-Gaussian localized vortex wave with broader initial half-pulse width has stronger resistance to oceanic turbulent perturbation. This work provides a theoretical basis for realizing high capacity oceanic optical communication with carrier Bessel-Gaussian vortex localized wave.

A simple and effective interference fading suppression method for Φ-OTDR using optimal peak-seeking is proposed. This method can reconstruct the vibration signal with high fidelity under the premise of using only ordinary single-mode sensing fiber without changing the structure of the traditional Φ-OTDR system. Based on the data after interference suppression, we applied different machine learning models to recognize the invasive events category. The promising results show potential applications of Φ-OTDR equipment and future implementation with machine learning algorithms.

Phase-sensitive optical time-domain reflectometry (Ф-OTDR) has been widely used to interrogate multi-point vibration events in the health monitoring and damage detection of civil infrastructures, mechanical processes and aerospace transportation. Due to the different lengths of the events, the spatial resolution (SR) requirements would also be different. This paper presents and demonstrates two kinds of Φ-OTDR sensing systems with multi-spatial resolution (MSR) analysis characteristics. Frequency division multiplexing (FDM) and multi-scale matching filtering schemes were introduced to provide MSR ability for the phase-discrimination and amplitude-discrimination Φ-OTDR systems respectively. The proposed methods could restore vibration events of different scales with optimum signal-to-noise ratio (SNR) in merely a single measurement while maintaining the detectable frequency range, which offered promising solutions for the performance optimization of Φ-OTDR sensing systems.

The long-term beamwidth and quivering of modified Bessel Gaussian Schell vortex beam in oceanic turbulence are derived based on the extended Huygens-Fresnel principle. With the help of these models, we analyze the effect of vortex beam and turbulence parameters on long-term beamwidth and beam quivering. We find that modified Bessel Gaussian Schell vortex beam has smaller beam quivering when beam has higher orbital angular momentum quantum number, larger beam waist, larger width parameter, longer wavelength and lower coherent length. We also find that turbulence of large temperature-salinity contribution ratio, large inner scale of turbulence, large outer scale of turbulence and small rate of dissipation of the kinetic energy per unit mass of fluid is more likely to cause beam quivering. The variation trends of long-term beamwidth with beam parameters are opposite to that of beam quivering.

Utilizing the quantized Huygens-Fresnel principle, we study the effects of anisotropic non-Kolmogorov turbulence on the average polarizability of quantization Bessel-Gaussian Schell-model (BGSM) photon beams. We find that the average polarizability has a weak dependence on the outer scale. By decreasing the source transverse coherent width, transmission distance and receiver aperture diameter, or increasing wavelength and photon number, we can improve the average polarizability. In addition, the average polarizability increases with increasing inner scale and anisotropic factor, or decreasing refractive-index structure parameter. This work reveals that we can utilize higher number of photons, lower source transverse coherent width and longer “window” wavelength to improve the performance of a polarizationencoded free-space quantum communication system.

An improved data processing and analysis method is proposed to realize simultaneous monitor of multiple vibrations using polarization optical time domain reflectometry system. In our method, a differential trace of the frequency component along the fiber is got by doing subtraction of the distance traces with different number of vibrations at a certain frequency, and the vibrations vibrating at different time can be located by analyzing the response power variation of the differential trace. For multiple vibration points vibrating with the same frequency and at the same time, multiple vibration events can also be distinguished by extracting the modulated frequency component, and the frequency component is obtained at the starting or ceasing state of the vibrations because the initial phases of vibration sources are unsteady and different. With our method, a POTDR sensing system which can simultaneously monitor multiple vibration points over 3km with 10m spatial resolution is demonstrated.

The fast development of DNA-encoded chemical libraries (DECL) in the past 10 years has received great attention from pharmaceutical industries. It applies the selection approach for small molecular drug discovery. Because of the limited choices of DNA-compatible chemical reactions, most DNA-encoded chemical libraries have a narrow structural diversity and low synthetic yield. There is also a poor correlation between the ranking of compounds resulted from analyzing the sequencing data and the affinity measured through biochemical assays. By combining DECL with dynamical chemical library, the resulting DNA-encoded dynamic library (EDCCL) explores the thermodynamic equilibrium of reversible reactions as well as the advantages of DNA encoded compounds for manipulation/detection, thus leads to enhanced signal-to-noise ratio of the selection process and higher library quality. However, the library dynamics are caused by the weak interactions between the DNA strands, which also result in relatively low affinity of the bidentate interaction, as compared to a stable DNA duplex. To take advantage of both stably assembled dual-pharmacophore libraries and EDCCLs, we extended the concept of EDCCLs to heat-induced EDCCLs (hi-EDCCLs), in which the heat-induced recombination process of stable DNA duplexes and affinity capture are carried out separately. To replace the extremely laborious and repetitive manual process, a fully automated device will facilitate the use of DECL in drug discovery. Herein we describe a novel lab-on-a-chip platform for high throughput drug discovery with hi-EDCCL. A microfluidic system with integrated actuation was designed which is able to provide a continuous sample circulation by reducing the volume to a minimum. It consists of a cooled and a heated chamber for constant circulation. The system is capable to generate stable temperatures above 75 °C in the heated chamber to melt the double strands of the DNA and less than 15 °C in the cooled chamber, to reanneal the reshuffled library. In the binding chamber (the cooled chamber) specific retaining structures are integrated. These hold back beads functionalized with the target protein, while the chamber is continuously flushed with library molecules. Afterwards the whole system can be flushed with buffer to wash out unspecific bound molecules. Finally the protein-loaded beads with attached molecules can be eluted for further investigation.

Phase sensitive optical time domain reflectometry (Φ-OTDR) has been widely used in various applications for its distributed measurement capability of dynamic disturbance along the entire length of sensing fiber. In our previous research, the capacity of Φ-OTDR sensing system has been enhanced with ultra-weak fiber Bragg grating (UWFBG) array for high-precision quantitative measurement on the external disturbance. Multipoint ne level dynamic strain variation has been fully captured with 2m spatial resolution. However, only 5 identical UWFBGs were used in the demonstration. For large-scale sensing network, the detectable fiber length would be limited by the signal-to-noise ratio (SNR) and the dynamic range of the reflection signal. In this paper, the performance limit of the UWFGB array enhanced Φ-OTDR sensing system has been investigated. A numerical simulation was performed to illustrate the relationships between the SNR, sensing length, spatial resolution and the UWFBG reflectivity. The simulation results have shown that when the reflectivity is relatively low, the noise is mainly contributed from Rayleigh scattering. On the other hand, the multiple reflections will dominate the overall noise characteristic with the growing of UWFBG reflectivity. The requirement of detection dynamic range was also analyzed. Simulation has shown that lower UWFBG reflectivity will lead to smaller signal dynamic range, making the selection of detector more practicable. The analysis result is quite useful for designing large-scale sensing network based on UWFGB array enhanced Φ-OTDR sensing system in practical situation.

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.

The leakage light of an electro-optic modulator (EOM) induced by its finite extinction ratio (ER) may degrade the performance of Brillouin optical time domain reflectometer sensing system, especially for long distance measurement. In this letter, the configuration of a high ER probe pulse generator assisted by synchronous optical switch has been presented. A dual pulses interferometric method was also proposed to determine the dynamic ER value (DER) of the generated probe pulse. Contrast experiments have been performed to verify the effect of the proposed method in a BOTDR system and the results have shown that the performance of a long distance BOTDR sensing system can be improved observably with the proposed high ER probe pulse generator. At the end of a 48.5km sensing fiber, the maximum uncertainty of temperature measurement has been reduced from 5.2℃ to 0.8℃ with 25m spatial resolution after we improved the extinction ratio of probe pulse from 35dB to 65dB.

Stereo vision based 3D metrology technique is an effective approach for relatively large scale object’s 3D geometric detection. In this paper, we present a specified image capture system, which implements LVDS interface embedded CMOS sensor and CAN bus to ensure synchronous trigger and exposure. We made an error analysis for structured light vision measurement in large scale condition, based on which we built and tested the system prototype both indoor and outfield. The result shows that the system is very suitable for large scale metrology applications.

By researching the principle of colorimetric characterization method and Support Vector Regression (SVR), we analyze the feasibility of nonlinear transformation from scanner RGB color space to CIELAB color space based on SVR and built a new characterization model. Then we use the MATLABR2009a software to make a data simulation experiment to verify the accuracy of this model and figure out the color differences by CIEDE2000 color difference formula. Based on CIEDE2000 color difference formula, the average, the maximum and the minimum color differences of the training set are 1.2376, 2.5593 and 0.2182, the average, the maximum and the minimum color differences of the text set are 1.9318, 4.1421 and 0.4228. From the experimental results, we can make a conclusion that SVR can realize the nonlinear transformation from scanner RGB color space to CIELAB color space and the model satisfies the accuracy of scanner characterization. Therefore, SVR can be used into the color scanner characterization management.

In the color reproduction process, accurately predicting the color of recto-verso images and establishing a spectral reflectance model for halftones images are the great concern project of imaging quality control field. The scattering of light within paper and the ink penetration in the substrate are the key factors, which affect the color reproduction. A reflectance model for recto-verso color halftone prints is introduced in this paper which considers these factors. The paper based on the assumption that the colorant is non-scattering and the assumption that the paper is strong scattering substrate. By the multiple internal reflection between the paper substrate and the print-air interface of light, and the light along oblique path of the Williams-Clapper model, we proposed the color spectral reflectance precise prediction model of recto-verso halftone images. In the study, we propose this model for taking into account ink spreading, a phenomenon that occurs when printing an ink halftone in superposition with one or several solid inks. The ink-spreading model includes nominal-to-effective dot area coverage functions for each of the different ink overprint conditions by the least square curve fitting method, so the functions for physical dot gain of various overprint halftones are given. This model provided a theoretical foundation for color prediction analysis of recto-verso halftone images and the development of image quality detection system.

Based on the feature of the second-order FM halftone dots and the interaction feature among ink, paper and air, a spectral prediction model for the second-order FM halftone prints for the spectral Neugebauer random mixing model and dot-on-dot mixing model is developed by using a weighting factor to signify the correlation proportion of two models. The new spectral prediction model also includes the Yule-Nielsen effect by taking into account ink spreading in all ink superposition conditions. We create an ink spreading function for each superposition condition to indicate the difference of ink spreading for ink dots printing on different superposition, which maps nominal to effective dot surface coverage. Our results shown that in the ink jet printing, the mean and max ΔE difference between measured and predicted values are 2.90 and 7.26, smaller than the difference predicted by the model that is not taken into account ink spreading, which are 5.52 and 12.81. The prediction accuracy is considerably improved by the new model.

In the color printing process, the thickness and uniformity of ink have a great affect on the color reproduction. The ink thickness uniformity is an important parameters of measuring the quality of printing. Based on the fluorescent additives may absorb ultraviolet light and exit blue light or visible light and by considering the expansion of the ink, optical properties of paper with fluorescent additives , the internal lateral spread of light in paper with fluorescent additives and the fluorescent Clapper-Yule spectral reflectance prediction model, we introduce two factor parameters which are the initial thickness of the inks and the factor of ink thickness variation. A model for deducing ink thickness variations of printing on the fluorescent substrate is developed by the least square method and the spectrum reflectance of prints which measures the ink thickness variations. The correctness of the conclusions are verified by experiment.

When ink jet printers' drop size change, based on Clapper-Yule model, study reflectance prediction model for variable dot-size ink jet presswoke. At first, this article introduce variable drop size and the FM screening form of Clapper-Yule model; then, using the change of ink film thickness and FM screening dot, which are caused by drop change, extended Clapper-Yule model; at last, established the Clapper-Yule model which is extended by drop size, in addition, validated the advantage of the model by simulation.

The research of color prediction model is one of the most important tasks in print reproduction. By the conception of regular quadriface composed of two bifaces we obtain the global transfer matrix of the quadriface from the single-step transition probability matrix of the Markov chain. According to the optics character of transparent plastic substrate, using the Markov chain of stochastic process theory, considering the fact of total reflectance when light propagate to optically thinner medium (air) from denser medium(ink and plastic substrate),we modify the mathematic model of reflectivity and obtain the mathematic reflectivity model of plastic substrate homochromous presswork.

By analyzing the different paths that the incident light traverses in the printing, the paper aims to study the effect the transmission of light produces on the color reproduction of the plastic printing. The article also analyzes object characteristics about the three color properties and the color density, so as to make an accurate prediction on the color reproduction of the printing where ink is printed on the end of the plastic base directly. In the research, the incident light on the plastic print are divided into two parts: the reflection of diffuse light in the ink and the optical multi-layer internal reflection of the light through ink layer onto the plastic substrate. In this paper, we use kubelka-munk theory to analyze the transmission of the incident light on the surface of the printing product and Clapper-Yule theory to analyze the incident light which through the ink to the plastic film surface. When the incident light through the ink to the film surface, we have a series of mutually parallel reflected beam and refracted beam, and then obtain the synthesis of the reflected light complex amplitude, using the similar methods to obtain the total reflected and refraction light intensity. Combining the total reflection light intensity through the plastic substrate and the overall reflectivity through a plastic print surface by the kubelka-munk theory, color density and light transmission factor of the plastic substrate can be drawn in the formula: D ∞ f (δ, d , i 1 ). From the above equation, we can find that optical phase retardation δ, the thickness of plastic d and the angle of incidence on the plastic surface i 1 affect the color reproduction of plastic print.

Fluorescent brighteners in paper can emit visible blue lights or fluorescence after absorbing invisible UV (ultraviolet) lights and the visible blue lights can increase the whiteness of the paper in the visual effects. In this paper, we use the enhanced Clapper-Yule model to establish a new predicted reflectance model for halftone image. The reflective law of halftone image on fluorescent supports is generalized by utilizing the idea that the reflected light by fluorescent supports is divided into two parts: the primary streams which consist of originally incident light and the fluorescent streams which are created by absorption of the UV lights. Firstly, the spectral reflectance of the vacant fluorescent supports and ink layer on fluorescent supports are analyzed. Secondly, the reflectance and transmittance of ink layer on fluorescent supports are studied. Then the physical dot gain that results from the real extension of an ink dot (i.e., ink spreading) is studied. Finally, we establish a reflection and transmission model for a halftone image on paper with fluorescent additives. To prove the accuracy of the model, we make data simulation with Matlab software and two reflectance curves (the reflectance of halftone image on paper with and without fluorescent additives) were generated. From the results, we can make a conclusion that the new model has a good accuracy to predict the reflectance of halftone image on fluorescent supports.

Chip packaging is an important process during IC manufacturing. Wire bonders are key equipments of chip packaging. The manually type of wire bonders can be updated to automatic with a pattern recognition system (PRS). However, the resolution of PRS is quite sensitive to the mechanism's trembling. Additional waiting time has to be taken before the image sensor can take a shoot, which limits the wire bonder's productivity. In this paper, method for motion blurred image restoration is presented. The method uses point spread function (PSF) learning to estimate the degradation function and power spectrum analyze to estimate the image's signal to noise rate (SNR). Experimental results are given to illustrate the proposed image restoration algorithm.

A photon communication system based on orbital angular momentum (OAM)-carrying beams is studied. We compartmentalize the atmospheric aberration into tilt,coma, astigmatism as well as defous. We numerically analyze the effects of tilt on the orbital angular momentum of communication beams and find that the tilt aberration can induce the noisy OAM. With the increasing of parameters P, L, the probability of initial OAM goes down while the effective number of noise OAM increases. At the same time, the peaks of the induced OAM probability (max-probability) are different as the P, L, changes. The increase of zenith angle damages the probability and leads to noisy OAM. This can also be applied to the impact of refractive index structure parameter. We also numerically analyze the effects which receiving-radius puts on the receiving probability of initial OAM through tilt aberration. Under the influence of tilt, the receiving probability of previous orbital angular momentum slashs with the receiving-radius becoming large.

It developped the Kubelka-Munk model and established a prediction model of fluorescence prints.Based on this,it was developped to the halftone prints and we introduced the scattering probability function which was calculated by the experience probability model. So we can establish an complete prediction model of halftone fluorescence prints.

The color prediction of fluorescent ink security printing is a very concerned issus in the field of security printing quality control. This paper first analyzed the light transmission of solid fluorescent ink prints.We make the assumption that the absorption of ink layer and the the radiation of fluorescence are all occur on a very thin layer in the middle of ink layer.And the produced fluorescence are only in upward and downward direction. Under such assumption we analyze the light spreading in fluorescent ink layer of the absorption, scattering and fluorescence of radiation, respectively. So we divide the incidence into three parts. The first is the light reflecting by the air-ink interface.The second part is the upward and downward fluorescence which radiating by the thin fluorescence layer. The third part is the remanent incidence after the absorption of thin fluorescence layer.Through researching the three transmission beams in the dissemination of the dynamics of the ink layer we can calculate the light the reflectance and transmission of fluorescent ink layer using the iterative algorithm.Then using the Murray-Davies model which reflecting the light propagating in halftone ink layer we establish the new reflection Murray-Davies model of halftone fluorescent ink prints.

Through the analysis of the light scattering within the ink and paper. we provide the fact of the total incident flux that contains both the collimated flux and the diffuse flux which were caused by the specular reflection and diffuse reflection on the air-ink interface in the process of color reproduction. Considering the phenomenon of the energy of these two parts of the flux are changing constantly, the four-flux kubelka-munk model based on the radiative transfer equation is given. Also, a new four-flux model for calculation of the reflectance of print with rough substrate is established with the Beckmann-Spizzichino model which describe the reflectance of the incident flux with arbitrary rough substrate.

In 1931, Kubelka and Munk introduced two-flux Kubelka-Munk model based on radiative transfer theory[1]. But the model has lots of strict conditions. In 1942, Saunderson introduced revised method, for there would occur multiple inside reflection in the interface of print, and it would induce density increase in the ink layer, and influenced prediction precision. Dot gain is always the difficult problem in print, it includes physics gain and optical gain. Kubelka-Munk model didn't consider dot gain's effect, especially optical gain. There are many methods to calculate dot gain. Many of them are based on point spread function principle[5]. Recently, Yang Li corrects the scattering coefficient S and absorption coefficient K in the Kubelka-Munk model based on statistical physics theory[2][3][4]. This makes the model has more widely applications. This article, taking into account of oil layer, oil penetration layer and paper layer respectively, thinking over multiple reflection and optical dot gain, builds a new halftone color prediction model.

The scattering of light within paper and the ink penetration in the substrate are the key factors which affect the color reproduction. A reflectance model for color halftone prints is introduced in this paper which considers these factors. The model is obtained by the extended Murray-Davies model and iterative algorithm. The model described in this paper contains two parameters, n and v . The n factor equals to the sum of w and v . The w factor relates to the optical spread function of paper relative to the spatial frequency of the halftone dots. The v factor relates to the distribution of colorant within the dots. The value of n and v are obtained by simulation according to the experimental data. For offset lithographic halftone data at 150lpi, the value of n and v are 1.578 and 0.02, thermal wax transfer halftone ( n =2.292, v =0.0209) and stochastic halftone ( n =1.1853, v =-0.006).© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Here we focus our discussion on symmetry analysis of image. A new method, Symmetric Point Pairs Sequence (SPPS), is proposed for skeletonization and applied to process complex intersections in biomedical images. Among many thinning algorithms, methods based on contour information have been explored popular recently. In many methods based on polygonal approximation of contour, Voronoi Diagram is applied to compute the Voronoi skeleton. But for each thinning algorithm, crossing region is a rather difficult problem, in which skeleton always deforms. In this paper the SPPS is described firstly. It is obtained through the Delaunay Triangulation for sampling points of the contour. In the crossing region whose structure is represented by the triangulation dual graph model, the SPPSs are merged and reconstructed. So the skeleton that isn’t deformed is obtained. We apply this method to process complex intersections in biomedical images. In the neuroscience field, a number of pathologies seem to be connected to morphological alterations of neural cells. In our experiment a lot of symmetric point pairs are displayed. The result shows this method preserve the precise the topological relation among the crossing regions, so our purpose to individualize all the real cells by different shape is reached.

We study the effects of finite outer scale and inner scale of atmospheric turbulence on aperture averaging of optical scintillations. Analytical developments of the aperture- averaging factor have been limited somewhat because of mathematical complexities associated with the integral G equals $CINTb 1 (Dx)K(x)xdx. In part, this is due to the MTF model K(x) that characterizes circular aperture and the power spectrum of refractive index fluctuations. So, we derive a modified spectrum of refractive index fluctuations that features inner scale, outer scale and a high wave number bump. And we approximate the circular aperture with a Gaussian aperture model. The analytic expressions are obtained for the aperture-averaging factor associated with optical scintillations of unbounded plane waves in weak fluctuation regime based on a modified spectrum of refractive-index fluctuations and the Gaussian aperture model. This analysis is inclusion of the finite outer-scale and inner-scale are shown to be necessary for quantitative estimates. Our results obtained for the modified model turbulence spectrum significantly differ from those obtained for a Kolmogorov turbulence spectrum. In addition, interpolation expressions are obtained for the aperture- averaging factor associated with optical scintillations of a spherical wave in weak fluctuation regime.

This paper restricts to the study of the effect of vignetting of dual beam scanning of polygonal scanners. The scanning of dual beam scanning field of a polygon scanner is not symmetric around any points or axes in the scanning system when the incident ray has an incident angle (theta) z. Therefore, in general, a symmetrical scan field distribution cannot be expected. In this paper, some fundamental aspects of the structure of the scan field, such as the effective scanning height of polygon, effect of vignetting and the scan duty cycle in y' direction are considered. The vignetting effect in z' directions are also analyzed and the condition of the vignetting free is given. From discussion, we can conclude that to educe the processing area of polygon facet, the condition of (theta) y < arcsin(RF/(chi) 0) is needed.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this paper, a rigorous vector analysis is performed to investigate the asymmetry of dual beam scanning field produced by a rotating polygon. Some basic equations of dual beam scan are derived, such as, the position vector for the incident point, the scalar expression for reflected ray, scan pattern on observation plane etc. Based on these equations, the asymmetry of scan angle and velocity are discussed, and it is shown that the reduction of the incident angle (theta) y, (theta) y and the x0/RF, the increase of the number of polygon facets will decrease the asymmetry of scan angle. The small values of (theta) y, x0/RF, P/RF in a range of 1.3 approximately 1.6, and small scanning angle in near-field help to reduce the asymmetry of scan velocity.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

From the view of the optical information theory, we study the transfer of the image's information content by imaging integral equation. We, in terms of a set of complete orthogonal eigen functions, expand the images of the manuscript in Karhunen-loe've series, the Karhunen-loe've basis is prolate spheroidal functions. The resolution of images is represented by the number of significant eigenvalues (also called modes of degree of freedom) of expansion. We analyze the influence of the shape of the scanning sampling objective aperture of scanning device on the definition (or resolution) and quality of the color- separation image. By analyzing the definition and signal to noise ratio of the color-separation images, we obtain the conclusion that, under the condition that the sampling way and the number of scanning lines are same, the quality of the color-separation images sampled by the square objective aperture is better than that sampled by the round one.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We study the detectional theory of polydispersities for dilute suspension of optical and size polydisperse spherical particles for which the Rayleigh-Gans-Debye approximation is valid. Tho develop the theory a concentric core-shell hard sphere model is adopted, in which particles possess a continuous variation in the core size and shell thickness. The thickness of shell is directly proportional to the radius of core, thus giving rise to a distribution in the particle refractive indices. We assume the shell thickness L equals (alpha) R, where (alpha) < 1 and is a constant. We extend the 'measured' dynamic structure factor to the general case where optical and size poly-dispersed are combination and a new 'measured' dynamic structure factor to the general case where optical and size poly-dispersed are combination and a new 'measured' static structure factor Sm (K) is derived. We analyze the dependence of the average scattered intensity I(q) and the effective diffusion coefficient De(q) which is obtained from the first cumulant measured by dynamic light scattering in the case of the refractive index of the solvent and the refractive index of the shell are matched, i.e., nm$ equals n(subscript s, on scattering vector q. Under favorable conditions it should be possible to measure small polydispersities.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

There are two sections in this paper. First, by using physical model of -4- bound, the statistics propertiesof scattering particles are studied ; the velocity autocorrelations function and the mean-square displacement ofscattered particle under our physical model are got ; we discuss the different a values for different bound model. Second, the scatteded electrical field autocorrelation function of dynamic light scattering through bound scattering particles is calculated. The resules of this paper, we think can been compared with resules experimentand a value for different solution may been obtained. Keywords : 4 bound, Brownain particles, DLS. 1. INTRODUCTION In the theoretical and experimental study of dynamic light scattering. interparticle interactions are generally interested recently. A lot of physical models of interparticle interactions were studied'5. Tung Tsang andH. T. Tang3 have reported studies of the light scattering and dynamics of interacting Brownian particles byusing a harmonic approximations for the effective potential; P. N. Pusey and W. Van Megen4 researcheddynamic light scattering by non-ergodic media, in which the scattering element's are only able to make limited

The double-passage effects of atmospheric turbulence on the imaging quality and resolution of an optical system , illuminated by the incoherent light ,are discussed in terms of the information content and the nUmber Nd of degrees of freedom of an imaging system. The Van Cittent-Zernike theorem and the Karhunen-Loe've expasion of generalized prolate -spheroidal function for the mutual intensity of stochastic waves is used to calaulate the turbulent average mutual intensity f12 for light from an extended incoherent quasi -monochromatic source and double-passage propagation in weak atmospheric turbulence. It is shown that , for incoherent illumination system and the receiving aperture is larger than the radius A of backscattered beam ,the turbulent spread of the beam may lead a positive effect , and there is a potential supperresolution , the resolution beyond the classical diffraction limit.

The effect of the quality of printing paper, which is a main factor of the reproduction of picture and char-acter, on the reproduction quality of picture and character by the optical information theory is studied. Theoptical transfer function that is applied to evaluate the imaging character of printing paper is obtained.Keywords: optical transfer function, printing paper, printing quality

This paper presents a unsymmetrical wavelength multiplexing system on the basis of concrete conditions to improve the image quality and resolution of fiber optics telescope. Different combinations of prisms and lens are chosen as long as wavelength multiplexing systems have identical line dispersion. Accordingly, if the magnification of the original fiber optics telescope is (Gamma) , only two prisms with 1 : (Gamma) angle dispersion ratio placed before objective and after eyepiece respectively can meet the above demands. In the fiber optics telescope we designed, the system's magnification is 2.8X. The two prisms' angle dispersion are 18'30' and 52'18' respectively. The angle resolution of the telescope is 23', and it is improved by 70 percent compared with that of the original fiber optics telescope.

We consider dilute suspensions of optical and size polydisperse spherical particles for which the Rayleigh-Gans-Debye (RGD) approximation is valid. To develop the theory a concentric core-shell hard sphere model is adopted, in which particles possess a continuous variation in the core sizes but have constant shell thickness, thus giving rise to a distribution in the particle refractive indices. For two-component system, we theoretical analyze the dependence on scattering vector q of the average scattered intensity I(q) and the effective diffusion coefficient De(q) obtained from the first cumulant measured by dynamic light scattering in the case of the refractive index of the solvent and the refractive index of the shell are matched, i.e., nm equals ns. Under favorable conditions it should be possible to measure small polydispersities.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The effects of the wavelength multiplexing on the quality of an image transferred through a fiber bundle system is discussed by using the information capacity of an imaging system. The image transfer through a conventional fiber bundle can be thought of as a discrete sampling of the illuminance of the image at the entrance and of the bundle by each fiber element. This discrete sampling limits the band width of signals which can be transmitted. Also, the ends of the component fibers form an obtrusive pattern in the received image. Because, in the dispersion fiber bundle system, each fiber integrates the flux falling upon its entrance aperture, the entire picture format dispersion scan is reproduced at the frequency response characteristic of a uniform disk whose diameter is equal to that of the component fibers. Also, the individual fiber ends are thus blurred out and the obtrusive pattern formed by them is destroyed. It is shown, in theory, that the use of a dispersion method makes it possible to reduce the value of the light transmission nonuniformity contrast and to improve the resolution of fiber bundle image system, respectively.

The effects of atmospheric turbulence on the imaging quality and resolution of an optical system, illuminated by the coherent and noncoherent light, are discussed in terms of the information content and the number Nd of degrees of freedom of an imaging system. lt is shown that, for coherent illumination system and the receiving radius R2 is langer than the radius a of propagated beam ,the turbulent spread of the beam may lead a positive effect , and there is a potential superresolution, the resolution beyond the classical diffraction limit and for R2 < at ,the Nd is independent on the atmospheric turbulence. For the particuar cases of incoherent illumination, Nd is found to be reduced from its turbulence--free value , the Shannon number , by the factor ((alpha)r0/D0 ) 2, r0 is the Fried's parmenter , D0 is the receiving diameter and (alpha) is the function of the variable r0/D0. The information content of coherent incoherent illumination systems is decrease with the atmosphere--turbulence fluctuations increase.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In the study of dynamic light scattering (DLS), the autocorrelation function of the scattered light is one of the most important problems. Through the relationship between autocorrelation function and autocorrelation function of scattered light intensity, using the technology of photon correlation spectroscopy (PCS), we can measure the physical and the chemical properties of the illuminating system. In the illuminated system, the Brownian movement of the scattering particle is a result of dynamic light scattering. In this paper, calculations are presented of the autocorrelation of scattered field by a monodispersion system of spherical particle in colloid following statistical properties of Brownian movement and theory of classical electromagnetic field. The approximation of results which we get was the same single exponential functions in general use, and the results applied to the situation for the Brownian particles in an electric field. The spectral density difference between the two situations is discussed and it is suggested that this result may be employed in the experiments of the quantitative analysis of mixtures of charged macromolecules in colloid.