A simple method based on CFD code and Matlab for aero-optic effects is presented. Density fluctuation from CFD code due to the changes of such factors as altitude, speed, equipment location, and wavelength is introduced as an input to Matlab. The overall calculations are in Matlab. The results show that the performance of electro-optical (EO) system can be improved when the altitude increasing, the speed is as slowly as possible, and the equipment location moves to the leading edge of the airborne platform as far as possible, for the wavelength there is an optimum one when the indexes of contrast and resolution of the system are both considered. All of these methods can minimize the optical aberrations. Several numerical simulations demonstrate the method.

The multi-photon ionization spectrum of NO in the wavelength region of 575-680 nm is obtained with an optical parameter generator and amplifier (OPG/OPA) pumped by a picosecond Nd:YAG laser as radiation source. The banded structure of the spectrum indicates that NO molecule is ionized in resonant manner and the peaks of the spectrum are assigned to the transition of NO molecule from the ground electronic state to A2'Sigma' (v'=0,1,2,3), E2'Sigma' (v'=0,1,2), F2'Delta' (v'=0,1,2,3) and H2'Sigma' (v'=0,1,2) intermediate resonant ones. The molecule constants about NO (A2'Sigma', E2'Sigma', F2'Delta', H2'Sigma') states are calculated from the center wavelength of the spectrum. It is also found that owing to the special electron configuration of NO, this molecule does not follow the normal transition selection rule of the diatomic molecule during the multi-photon process.

Photonic crystal fibers (PCFs) with a stepped raised-core profile and one layer equally spaced holes in the cladding are analyzed. Using effective index method and considering a raised step refractive index difference between the index of the core and the effective index of the cladding, we improve the characteristic parameters such as numerical aperture and V-parameter, and reduce its bending loss to about one tenth of a conventional PCF. Implementing such a structure in PCFs may be one step forward to achieve low loss PCFs for communication applications.

A numerical design on the triangular photonic crystal fiber (PCF) based backward multi-pump Raman amplifier is presented. It is demonstrated that high flat Raman gain can be reached based on PCF. Influences of different geometric parameters and germanium doping concentrations on the Raman net gain, amplified spontaneous emission (ASE) noise and double Rayleigh backscattering (DRBS) of the signal have been analyzed. For optimizing crystal fiber Raman amplifier (FRA), there is tradeoff between the geometric parameter and germanium doping concentration of triangular PCF. The results show that PCF is an appropriate candidate for high gain Raman amplifiers.

A novel nonlinear optical loop mirror (NOLM) with a nonreciprocal phase shift bias (NPSB), called power equalization NOLM (PE-NOLM), is proposed for reducing the power fluctuation of pulse trains. NPSB provides part of the nonreciprocal phase difference so that the required input power is reduced, and nonsymmetrical coupling ratio of coupler can adjust the transmission curve to improve the equalization range. It has been shown theoretically that compared with earlier PE-NOLM, about 1.6 dB of equalization power reduction and about 2.2 dB of equalization range enhancement could be achieved. Experiments have demonstrated that the output power fluctuation is reduced to less than 0.4 dB, while the required input peak power range is 4.5 dBm (15.6-20.1 dBm).

Target dynamics are assumed to be known in measuring digital speckle displacement. Use is made of a simple measurement equation, where measurement noise represents the effect of disturbances introduced in measurement process. From these assumptions, Kalman filter can be designed to reduce variance of measurement noise. An optical and analysis system was set up, by which object motion with constant displacement and constant velocity is experimented with to verify validity of Kalman filtering techniques for reduction of measurement noise variance.

A novel methodology to integrate edge feature and edge-spatial feature of an image is proposed. The edge feature is described by edge histogram of image, the edge-spatial feature is described by spatial distribution of pixels of identical edge value in the image. Experimental results show that the method can achieve better retrieval performance, especially for color natural images with more complex spatial layout.

It is difficult and high-cost to detect flame fronts by laser-sheet diagnostics under microgravity (micro-g), thus image processing is critical to obtain valuable information from the raw data. In the present study, premixed V-flames were detected under micro-g by OH planar laser-induced fluorescence (PLIF) and an effective method based on active contour model (ACM) is presented for automatic detecting and tracking flame fronts in the PLIF images. ACM can effectively detect the flame front in the images with low contrast and noises. Compared with other methods of flame front detection, the advantage of this method is that the image smoothing and image enhancement are not necessary for the correct detection of flame fronts in raw PLIF images.

An optical biosensor with up-converting phosphor (UCP) marker is developed for the sensitive rapid immunoassay to the specific biomolecule. UCP can emit visible light when excited by infrared light. Through detecting and analyzing the content of UCP particles on the test strip after immunoreaction, the concentration of target analyte in the sample can be obtained. The detection sensitivity to plague IgG is better than 5 ng/ml; to plague FI-Ab is better than 100 pg/ml; to plague Yersinia pestis cell is better than 3*10^(4) CFU/ml. Good linear response characteristics and an excellent correlation (R2&gt=0.95) have been verified by quantitative detection results. In the practical application, detection results to 167 analytic samples have an excellent consistency with those obtained by reverse hemagglutination test. The up-converting phosphor technology (UPT) based biosensor has stable, reliable, and sensitive performances. It can meet the need of various bioassay applications.

The theoretical investigation of all parameter noises in repetition-rate laser pulse train was presented. The expression of power spectrum of laser pulse trains with all parameter noises was derived, and the power spectra of pulse trains with different noise parameters were numerically simulated. By comparing the power spectra with and without pulse-width jitter, we noted that pulse-width jitter could not be neglected compared with amplitude noise and timing jitter and contributed a great amount of noise into the power spectrum under the condition that the product of pulse width and angular frequency was larger than 1.

A tunable continuous wave (CW) low temperature operating Tm (6 at.-%),Ho (0.6at.-%):YLF laser pumped by fiber-coupled diode laser is reported. The maximum output power is 4.16 W at 2073 nm by use of 30% output coupling, the slope efficiency is 33%. A tuning range from 2049 to 2081 nm is achieved with a birefringent filter (BF). The factors that contribute to the output power and tuning range are discussed.

The effects of laser energy and different shock spaces and shock times on the TA2 titanium sheet deformation are investigated experimentally and simulated numerically by ABAQUS software. The results indicate that the amount of TA2 sheet deformation increases with the increase of laser energy, varies with shock order and shock path, and is the greatest when the shocks are along the length of sheet and symmetrical. The numerically simulative results are consistent with the experimental data.

The xNb2O5-(15-x)La2O3-40B2O3-45BaO (x=5, 7.5, 12.5 mol%) glasses doped with Eu3+ ions in 1 mol% are fabricated by the melting method. The Fourier transform infrared (FTIR) spectra, phonon side-band spectra, emission and excitation spectra of the glasses are measured. The crystal field parameter and coordination number of Eu3+ ions in the glasses are obtained according to the splitting of their 5D0-7F1 levels. The intensity parameters 'Omega'2 and 'Omega'4 of Eu3+ ions for optical transition are calculated from their emission spectra in terms of reduced matrix U(t) ('lambda'=2, 4, 6) character for optical transitions. The results indicate that the intensity parameters 'Omega'2 and 'Omega'4 increase with the increase of Nb2O5 content, suggesting that the symmetry becomes lower, the band of Eu and O atoms becomes stronger and the covalence increases with the increase of Nb2O5 content.

The nonlinear optical properties of a new organic material, N-vinylcarbazole tricarbonyl chromium, are reported. The large two-photon absorption (TPA) coefficient and nonlinear refraction index are measured by an open-aperture Z-scan technique and closed-aperture Z-scan technique, respectively. The sample solution shows excellent optical limiting response.

In the field of optical interconnecting network and in super fast photonic computing system, the tree architecture and optical nonlinear materials can play a significant role. Nonlinear optical material may find important uses in optical switching. Optical switch using nonlinear material makes it possible for one optical signal to control and switch another optical signal through nonlinear interaction in a material. In this communication such materials have been successfully exploited to design an all-optical tree-net architecture, which can be utilized for time division multiplexing scheme in all-optical domain.

The quantum phase and the related fields have attracted considerable attention. The geometric phase of spin-1/2 particle in the magnetic field has been discussed comprehensively, but few of spin-1. In this paper, the exact solution of spin-1 was obtained by using rotational frame method. The problems of the Rabi oscillation, dynamical phase, and geometric phase were solved.

The spectroscopic data recorded by dispersion spectrophotometer are usually degraded by the response function of the instrument. To improve the resolving power, double or triple cascade spectrophotometer and narrow slits have been employed, but the total flux of the radiation decreases accordingly, resulting in a lower signal-to-noise ratio (SNR) and a longer measuring time. However, the spectral resolution can be improved by mathematically removing the effect of the instrument response function. Based on the Shalvi-Weinstein criterion, a Gauss-Newton based kurtosis blind deconvolution algorithm for spectroscopic data is proposed. Experiments with some real measured Raman spectroscopic data show that this algorithm has excellent deconvolution capability.

A Nd:YAG pulsed laser is used to ablate HgCdTe target at different ambient pressures, the emission spectrum is detected by a time- and space-resolved diagnostic technique. It is found that the characteristics of time-resolved emission spectra are influenced by the pressure of background gas. A theoretical model is developed to investigate expansion mechanism of plasma, the time evolution of the propagation distances and the velocities of plasma plume are calculated by the model at pressures of 101000, 1000, and 5 Pa, respectively. The calculated results are well consistent with the experimental data.