A new treatment of the behavior of TE waves in a planar waveguide with Kerr type nonlinearity is given in the weakly nonlinear approximations. Dispersion equations and field profiles with clear physical insight are presented. This method simplifies the numerical calculations significantly.

The basic characteristics of double pass forword superfluorescence of Nd 3+ dopedfluoride glass fiber, such as input output, output linewidth, and output wavelength (exciting) of the superfluorescence have been studied. The fitting formulae are given. The experiments suggest that the superfluorescence of fluoride glass fibr is a kind of low coherence and high performances light source with bright application prospect.

Optical coherence tomography (OCT) has been analyzed theoretically as an imaging system upon the weak object approximation. It has been proved that the OCT system behaves as a linear shift invariance system and can be described precisely by a coherent transfer function (CTF). The derived longitude CTF has shown that the system performs like a low pass filter with a FWHM Δ k=2 Δ λ/λ 2 . High spatial frequency structure is detected because the spectrum of the object shifted a distance of 1/λ . This research will provide a theoretical basis to quantitatively analyzed the measuring results of the unknown structure and to increase further the spatial resolution.

A method of lensless one step rainbow holography for diffuse 3-D objects with a synthetic slit is proposed. The visual field of the reconstructed image is extended and is not limited by the aperture of the lens. A theoretical analysis and some experimental results are presented.

The general performance of amplified spontaneous emission (ASE) in large scale laser systems is discussed. The measured ASE results on TW SHENGUANG facility are given.

The linear relation of gain on carrier density in the conventional rate equation is replaced by the logarithmic relation for quantum well lasers in this paper. The static and dynamic behaviors brought by the revision are analyzed. An optimal well number for the minimum threshold currenl and an optimal cavity length for the highest modulation frequency have been obtained.

The steady state of a single mode laser driven by additive and multiplicative noises with an arbitrary degree of negative correlation is studied. With negative correlation, the mean, variance and skewness of the steady state laser intensity are calculated. Comparing with the situation of postive correlation, some significant phenomenon are found.

The effect of pre pulse on line shaped laser produced plasma X-ray radiation was studied. The intensity of pre pulse is 10% of that of mainpulse, the duration of each pulse is 120 ps, and the delay of main pulse to pre pulse is 200 ps. The spatial characteristics of the pre pulse effect were obtained, and some important transitions and their physical origin were discussed.

In this paper, superthermal electrons produced in laser plasma interaction transportation through solids was simulated using Monte Carlo method. In this simulation, we used a single scattering model based on continuous slowing down approximation (CSDA) and the Born approximation. Assuming the monoenergetic and spatially beamlike superthermal electron distribution, the different K α yields of different substrates overcoated with variable thickness Al layers are given.

The linewidth effect of ceherent driving field on electromagnetically induced transparency in an excited state doublet three level atomic system has been studied. It is shown that the linewidth of driving field destroy the transparency of the medium.

In this paper, the photonic bands of the body centered cubic and the hexagonal close packed structures consisting of spherical air atoms are calculated using vector plane wave method. The results show that complete band gaps (covering the entire Brillouin zone) open up for both structures. It is revealed that the maximum refractive index modulation coincides with the widest band gaps and the optimum volume fraction of the atoms is structure independent. The photonic bands of the face-centered-cubic (FCC) structure consisting of spherical anisotropic dielectric atoms are also calculated. The results show that a complete band gap opens up, which is quite different from the FCC structure consisting of spherical isotropic dielectric atoms.

CW CO2 laser induced damage to several kinds of infrared window materials has been investigated. It has shown that the damage mechanism is attributed to thermal shock stress caused by the absorption of impurities and defects in the materials. We have established a model concerning the defect intensity and focus spot with damage threshold, and the damage modes of thermal shock stress are analyzed.

The transmissivities of photorefractive material KNSBN:Mn crystal have been measured, and its energy state structure is described. Based on the ligand field theory, mechanism and effect of the Mn ion on the photorefractive material KNSBN:Mn are discussed and the optical diode effect is explained from the point of view of microstructure.

By numerical method, the mechanism of optical pulse compression within the stop band of a fiber grating was demonstrated to be the process of energy storing and tuning out of the stop band. The envolope of energy density, which is a solitary wave like object, is firstly excited by the input pulse, then propagates along the fiber grating and losses energy at the output end to form an output pulse. The temporal width and peak power of the output pulse are determined by speed, spatial width, and peak value of the envolop of the energy density. The self-pulsting effect will induce the formation of multi-pulse output, which can be used for the bigger pulse-compression factor.

The effects of gain saturation (GS) in chirped pulse amplification are studied in this paper. It is found that the compressed signal to noise ratio (SNR) may decrease due to GS and the dispersion added by stretcher. The decreasing corresponds to distortion in frequency domain. The analysis on the stretcher/compressor shows the internal relation between spectroscopy and time intensity. It is advised that frequency mismatch may be used to modify the spectral shape and increase SNR.

The 255.3 nm light of a frequency doubled copper vapor laser is used to study the photorefractivity of hydrogen loaded fibers for the first time. The measured refractive index change is found to be large enough to make practical gratings in the fibers.

The N type properties of reflected bistable optical devices (RBODs) are studued by using the accuracy matrix formulas based on the principle of thin film optics. The relationship between δI 0、 δI r and δ, which are all the important parameters of RBODs, is plotted. The dispersive relations of ZnSe thin film are intoduced into the method to make the theoretical method self consistent. Finally, experimental result of a RBOD of nonlinear interference filter is given.

In this paper, it is proved that the beam cross section momentum and its any component of monochromatic field in vacuum are all invariances and independent of the position of the cross section, provided that the evanescent waves of the plane wave spectrum of the beam are ignored. The expression of the beam momentum diffraction divergence is derived.

The relationship between Bidirectional Reflectance Distribution Function (BRDF) and Laser Rader Cross Section (LRCS) is introduced by means of the electromagnetic radiation and scattering theories. The experimental measurements are made for BRDF of various samples with roughness at wavelength of 0.63 μm, and the influences of the surface height standard deviation, the correlation length and dielectric constant on BRDF are considered. The partial measured data are in good agreement with theorical calculation.

Effciency of an integrated optic modulator/switch depends on the overlap integral between the applied electric field and the optical mode. In this work, the field distribution of electrodes is analysed to determine the maximum overlap integral affected by the parameters of electrode width, interelectrode gap and optical mode size etc.. The results of the optimal electrode and waveguide design for Ti:LiNbO 3 modulators/switches are presented by utilizing a systematic optimization of all the necessary parameters according to the available technology.

This paper proposes an extended analytical model of the collection of scintillation light from a long and narrow plastic scintillator with the specular reflector. The light collection efficiency has been calculated.

The fundamental figure of merit of LiNbO3 deflector was studied based on the electro optic effect. Designning formula was derived. The electrical potential distribution over the deflector with four cylindrical electrodes was calculated by the mathod of finite difference. Refractive index gradient linearity and structure fractor were obtained for deffrent struture parameters.

The rotation invariant amplitude phase composite circular harmonic filter (CHF) is proposed. It gives an amplitude spectrum as the inverse of a biased amplitude spectrum of the CHF, and a phase spectrum as the phase spectrum of the CHF. Computer simulation results show that the proposed filter yields a sharper correlation peak, higher signal to noise ration and better correlation discrimination compared with the CHF and the phase only CHF.

In general case a Gaussian Schell model (GSM) beam passing through ABCD optical systems is represented by the superposition of coherent modes.

Using a code programmed based on the Fortran, spectrum images can be reproduced on the computer screen with artificial colored and multi level grey methods. Processing functions of screen cursor location, instant read out of spectrum data and image rotation were realized. In addition, the contour and 3D graph deduced from the image can also be produced. This code can greatly improve the efficiency and precision in film image data processing.

The two color laser induced grating spectroscopy (TC LIGS) technique is used for determination of the nuclear spin of 127I . The second harmonic output (532 nm) from a Nd:YAG laser is split into two pump beams with nearly equal intensity. These beams intersect at an angle of 2.73 degree and are directed into the I2 sample cell. The interference of these beams produces a sinusoidal distribution of a excited state laser induced population grating and a ground state laser induced depletion grating in the iodine molecules. A narrow bandwidth dye laser is used as probe beam and directed to the laser induced gratings. The spectroscopic signal is collected along the direction of Bragg diffeaction. The nuclear spin of 127I is determined by the pump resonance: 32-0 R(55), probe resonance: 13-0 P(55), R(55) and the pump resonance: 32-0 P(52), probe resonance: 13-0 P(52), R(52) TC-LIGs lines. The result is 5/2.

Photon gated multiple spectral hole burning processes have been studied in a donor acceptor electron transfer system. The electron donors of this system are zinc tetraphenylbenzoporphrin and zinc tetraphenylbenzotribenzoporphrin, the acceptor is phydroxybenzaldhyde, and they are doped in the matrix poly(methyl)methacrylate. It is more effective to form high quality multiple holes by successively burning from the shorter wavelength side to the longer side. It is affected by the wavelength dependent phenomenon of laser induced hole filling. The main mechanism of this phenomenon is the exist of pseudo-phonon side band. The theoretical simulation shows fairly good agreement with the experimental results.