A convective turbulence system with a liquid medium (water or ethanol) that can be used for simulation tubulent atmospher for wavefront distortion compensation is described. After using the improved plate heater and cooler, a convective turbulence with wide intertial range similar to the spectra of atmospheric turbulence was obtained. Its turbulent intensity can be easily controlled and the optical characteristics of turbulence, such as stability, statistucs feature of turbulent and index of refraction fluctuation spectrum are better than that in the real atmosphere and can be repeated easy. So the system can be used for the experiments of adaptive optical compensation and for studying the interaction of turbulent and blooming, and light propagation through turbulent atmosphere.

Based on the vector modal theory for perfectly conducting rectangular aperture grating, the diffraction field was studied numerically. The distribution of diffraction efficiency and polarization with arbitrary incident direction and polarization was given. The effect of grating structure parameters (period, width and depth) on the diffraction field was discussed. According to the calculation results, a series of samples with different depth were made, and the measurement shows that the theoretical calcualtion agrees with the experimental results.

Enhancement of nonlinear optical susceptibility can occur in layered composite materials. The equivalent dielectric constant for TM modes in an optical waveguide of layered composite materials is analyzed. We find that under experimentally realizable conditions the nonlinear second enhancement of such a structure can exist because of the waveguide boundary effects.

Based on the coupled mode theory for polarized waves inside crystals and the linearized band transport model for photorefractive effect, the analytical expression of the dynamic range parameter, M/#, of a photorefractive crystal in a volume holographic momory is derived. Taking LiNbO 3:Fe and BaTiO 3 as examples, we discuss the influence of the impurity doping level, oxidation reduction state and geometric configuration of coupling beams on the dynamic range performance. For both crystals we found that the denser the donor concentration and the higher the oxidation level, the larger the maximum possible dynamic range. For BaTiO 3 crystal the optimum angle between grating wave vector and optical axis should vary with the angle between signal and reference beams.

Consulting Naik′s investigation on the stability of gelatin holograms, the experimental results the stability of DC MBDCG hologams is presented. Their machanism is discussed. A new technology for fabricating the water resisting coat is presented.

Multiple target detection using an amplitude modulated and power spectrum subtracted joint transform correlator is proposed. In this technique, the joint power spectrum is firstly modified by the subtraction of the power spectra of the input scene only and of the reference image from it, the resultant modified joint power spectrum is next multiplied by the amplitude modulated filter function. The effect of noise in the input scene on the performance of the joint transform correlator is analyzed and quantified. The technique is found to deliver a better correlation output and the capacity to accommodate noise in the input scene than both the fringe adjusted filter and the modified fringe adjusted filter based joint transform correlators.

A measuring technique using continuous frequency grating film is proposed, and it′s methoc and priciple are given. The method can be used in wide range of deformation studies. The measuring sentivity is adjustable ranging from 0 l/mm to 600 l/mm continuously, or even higher.

Refractive index profile and modal dispersion in single mode optical fibers are computed from the measured expansion coefficients of the near field, which is expanded in a series of Gauss Laguerre functions. The coefficients of the series are measured from the correlation intensity between the near field of single mode fibers and the Gauss Laguerre mode of filter fabricated by computer generated holograms. The main advantage of the proposed method lies in its inherent insensitivity against random measurement errors and low optical dynamic range of a detector.

Based on the theory of rough surfaces scattering, a numerical formula for calculating the laser radar cross section per unit area from randomly rough surfaces is derived by using the phase perturbation method. The laser radar cross section per unit area of some rough samples are computed at 1.06 μm. The numerical results are in agreement with experimental data.

The observation of fluorescence properties of cerium doped inorganic scintillators GSO, PbF 2 and BaF 2 using synchrotron radiation as a exciting source at the Beijing Synchrotron Radiation Facility is described and discussed.

Phase shift and dispersion properties of dichroic mirror used in femtosecond Ti:sapphire laser are investigated. A sudden change of reflective phase shift near central wavelength is observed. Because of this transition point the second and third order dispersion have a discontinuous point. The factors affecting the transition point are discussed in detail.

The characteristics of a LD pumped Nd:YVO 4 laser operating at 1.34 μm are reported. The maximum output power of 157 mW with a optical to optical conversion efficiency of 30.5% has been obtained at the incident pump power of 515 mW. Variations of the longitudinal modes and the amplitude noise power spectrum with the incident pump power have been studied. The phenomenon that each longitudinal mode has its own relaxation oscillation frequency has been found.

The quenching mechanism was studied in a quenched dye laser pumped by excimer lasers. For some pump pulses, the quenching effect of the quenched laser was analysed by laser rate equations. In addition some important parameters of the lasers were discussed.

Making self mode locking experiment using the 3 mm Ti:sapphire short rod and the improved asymmetric Z shape folding configuration, with quartz prisms as dispersion compensation element, we achieve low threshold self mode locking operation with 5 W pumping power of Argon laser and soft aperture mode Locking without any modulating element. The pulse duration is 15 fs with 80 nm spectrum bandwidth. The 400 mW average power is obtained.

In the multielectronic states model, the dissociative behavior of H + 2 in intense laser field is calculated with the two order split propagator algorithm. It shows that for high frequency laser pulse H + 2 is multiphoton dissociated under the considered laser intensity and the momentum distribution of dissociative fragment is nearly symmetric. But for lower frequency laser pulse the molecule field interaction is dominated by tunneling dissociation and the momentum distribution of fragment H + is asymmetric. In addition, the effects of the laser pulse shape on the dissociation probability and the dissociation dynamics of H + 2 are discussed.

The Rosencwaig Gersho theory of the photoacoustic effect is extended to the case of three layer solids. The general expression for the complex amplitude of the periodic temperature at the solid gas boundary is obtained. The phase and relative magnitude of the photoacoustic signal varying with chopping frequency for varies optical absorption coefficients, thermal conductivity coefficients and material depths are numeralty calculated and compared with the experimental results.

The vector small perturbation theory based on Ewald Oseen extinction theorem is developed to study the laser scattering from rough surfaces. Angular spectrum of the Hermite Gaussian beam is analysed in detail and a concept of wave front cutting apart is discussed. This concept leads to the consideration that the scattering of collimated laser beams can be approximately dealt with as that of plane wave if the total incident power is used as the normalization factor, but the slender beam scattering is quite different from the plane wave. Using the obtained results, it is discussed theoretically that the concealment of 1 D rough surfaces from active detection and the scattered polarization at specular and back direction under the illumination of a ellipse polarized beam. Then distribution difference of the scattered light of vertically and horizontally polarized laser beam is introduced. The dominant conclusions are verified.

A novel bifat chain amphiphilic molecule nitrogencrown (NC) in Langmuir Blodgett (LB) films was characterized. The NC was adopted as an inert material for fabrication of optical nonlinear LB multilayers. The second harmonic generation (SHG) intensity increased quadratically with the bilayer number (up to 116 bilayers) in Y type hemicyanine (DAEP)/NC interleaving LB multilayers due to improvement of the structural properties by insertion of the long hydrophobic tail of DAEP molecules between two chains of NC molecules. The second order nonlinear susceptibility χ(2) ZXX (-2ω; ω, ω)=18 pM V -1 (or 4.4×10 -8 esu) was obtained by measuring SHG from the DAEP samples. The NC molecule has attractive features as a matrix material in fabrications of LB multilayers made from optically nonlinear molecules with hydrophobic long tails.

Principle and charecteristics for all optical signal amplification with Er doped fiber optical bistable devices are discussed. The optical gain under constant light bais and pulse light bais and its variance with device′s parameters are calculated. The design principles of the devices are given.

The property of stimulated Brillouin scattering (SBS) excited by monochromatic light in absorption media is investigated. The distributed fluctuating source model is employed to describe the process of SBS built up from spontaneous Brillouin scattering. By using Fourier transform, we can obtain the power spectral density of the output Stokes wave, which is useful in predicting the threshold for the occurrence of SBS generation and linewidth of Stokes radiation.

In Ni:KNbO3, self-pumped phase conjugate reflectivities of 43% at 725 nm and 1% at 831.4 nm were obtained.

An all fiber Weak coherent optical fiber sensor(OFS) system for displacement measurement with a fiber Young′s decoding interferometer is proposed and demonstrated. The OFS of this kind avoids the fatale signal fading problem in whole coherence OFS, which is caused by the fluctuation of source wavelength and power, power loss in propagation, as well as the changes of polarization direction. The OFS system is not only of simple structure, easy adjustment, but also with high resolution up to 0.054 mm.

Based on coupled mode theory, we reduce the contradirectional coupled mode equation to Riccati differential equation by means of phase conjugate transform. The reflectivity, dispersion, time delay characteristics with constant coupling coefficient and Gaussian taper function coupling coefficient of linearly chirped gratings are analysed numerically. It provides an effective theoretical approach for design of desired chromatic dispersion compensator.

The physical design of superconductive solenoid wiggler and room temperature water cooling solenoid wiggler at the 3th generation synchrotron radiation source is presented. The magnetic field distrabution and the measurement of magnetic field in the narrow cavity of wiggler are discussed. The manufacture technical feasibility is analysed.

Based on quantum theory and multimode model, concluding the pump depletion, the second order quantum correlation as the function of interaction distance in stimulated Raman scattering (SRS) is calculated and analyzed. The analysis predicts that, in the absence of dispersion, the correlation between Stokes waves and the pump increases to unity when the increase rate depends on the ratio of the pump and input Stokes. In the limit, the results argee with the Raman generation theories and the semiclassical theories.