Optical fiber gratings will play very important roles in future′s optical fiber communication and sensing systems. The responses of non-uniform optical fiber gratings with different types of apodising and chirping structure are numerically studied. Based on the general of non-symmetric response of non-uniform optical fiber grating, two conditions for symmetric response are provided.

Based on the phenomenon of the frequency shift in Brilluion back-scattering light related to the strain of the optical fiber, a new strain sensing scheme is proposed. On the basis of the nonlinear optics, the linear relationship between frequency shift of Brilluion scattering and the strain of the fiber is derived. The reason of the lower requirement for the band width and line stability of the laser source is analyzed. The experimental setup and result are presented.

By analyzing the propagating equation of ultrashort optical pulses in a single mode fiber, the bright and dark solitary wave solutions of the equation are obtained. The results show that the ultrashort optical pulses can propagate in a single mode fiber in form of the bright or dark solitary waves without the soliton self-frequency shift. That is significant for the long distance and stable propagation of ultrashort optical pulses and the system of optical soliton with ultra-high speed.

Soliton interaction in dispersion-shifted fibers is studied numerically, including the effect of third-order dispersion. Results show that soliton interaction in dispersion-shifted fibers is stronger and, thence, plays a more detrimental role in soliton communication system than that in conventional fibers. It is also show that launching adjacent pulses with unequal amplitudes does not results in eventual suppression of soliton interaction in dispersion-shifted fibers. Finally, a new method is suggested for suppression of soliton interaction in dispersion-shifted fibers.

The optical soliton equation with nonlinear response delay term has been solved exactly, and a new type of optical solitary wave, which is deeply different with bright and dark soliton solutions has been found. The physical meaning of the kink and the possibility to observe the kink solitary wave in optical fiber experiment have been discussed.

By a method related to Bchlund transformation, the optical soliton equation with nonlinear response delay term has been solved exactly and a drifting kink solution has been found. The limit property of the kink solution and related physical problems has been discussed in details. At the end, it is pointed out that this equation is parametrically unstable at γ=0.

A smart structure is defined as an electrorheological material based structural system whose geometric configuration or inherent characteristics can be modified in response to environmental changes. When a tunable product with sensory and control capabilities is implemented, a smart structure is approached. Fiber optic sensors have certain advantages such as electro-magnetic environment insensitivity, high response bandwidth and structural flexibility, so they can be used as an optimal sensing network/system.

On the basis of localization error of the first order frequency spectrum associated with interferogram phase unwrapping by Fourier transform method, especially aimed at phase unwrapping for practical interferograms with nonstrictly parallel and equally spaced references, a method of localized matching filtering using Gabor wavelets is proposed. Multi-channel Gabor spatial filter set is constructed to get the best matched local spatial frequency in meaning of Mallat maximum modulo. At the same time noises and opaque objects can be removed. The method is proved more effective than conventional Fourier transform method for cases of nonequally-spaced references and seriously deformed fringes by applying it to simulated and real interferograms to reconstruct interferometric wave fronts.

Multiaperture connection in Cartesian coordinates is difficult to be used to test suface of 3-D object or rotating object. To solve the problem, multiaperture connection in Cartesian coordinates is extended into cylindrical coordinates. Formulas in cylindrical coordinates are given. Results of computer simulation show that the theoretical error is about 10-7 mm, which proves the method is correct. Testing results for a real cylinder are given.

A new method is presented to extract quantitative information of Moire fringes. It is different from the method of phase shift. Instead of changing the phase of Moire fringe, it changes the frequency of the Moire fringe. The theoretical formula is introduced for a special relationship of three frequencies. For unwrapping the phase image, the first step is to expend the cosine value range from (0, π) to (0, 2π) to avoid the indetermination of “plus” or “minus”. The experimental result is given and the effect of light source position on measuring results are discussed.

The fractional Fourier transform hologram is presented, its properties are discussed. A fractional Fourier transform rainbow hologram is made, based on its particularity in reconstruction, a new type of anti-counterfeiting hologram is obtained.

Coupling between single longitudinal mode laser and single mode optical fiber encountered in the integrated method to shape the laser pulse is analyzed. It is concluded that to maintain the highest coupling efficiency, parameters of the laser cavity and the optical fiber must take into consideration in the designing of the coupling system. Conditions to realize an optimized coupling efficiency is also verified by experiments in which provides a basement for our future research.

The method of quantitative calculating of knife-edge testing for astronomical mirror polishing is discussed including shadow image CCD real-time collecting, image processing and the method of quantitative calculating of clitellum error.

A tunable fiber Bragg-grating (FBG) ring laser with stable, narrow linewidth and tunable output is demonstrated. Its tuning range is up to 5.7 nm, linewidth less than 0.1 nm.

Hydrophobic photostable laser dye molecules were incorporated into organically modified silicate matrices by the sol-gel technique. Successful laser oscillation of various pyrromethene dyes doped Ormosil has been achieved. Pumped with a frequency-doubled Q-switch Nd:YAG laser at 532 nm, the laser wavelength is tunable over 44 nm (550～594 nm). A slope efficiency of 61% was obtained from one of the dye-doped Ormosil in the millijoule output energy range. A useful lifetime greater than 2.5×104 pulses at a pump repetition rate of 1 Hz and a pump intensity of 1 J/cm2 was measured, with only a 10% loss in the available output energy.

The one-photon and two-photon excited UV fluorescence spectra of 1, 10-phenanthroline and ［bis(1, 10-phenanthroline)lanthanum］ nitrate are observed in the methanol solution. It is found that the UV fluorescence intensity of 1, 10-phenanthroline is obviously enhanced by virtue of its coordination with La3+, and the effect of La3+ as the role of a bridge improves the coupling process between two 1, 10-phenanthrolines in a complex, which results in the movement of the UV fluorescence peaks to longer wavelength.

Experimentul results of increased laser-damage resistance for optical materials by chemical treatment are reported. Laser surface damage thresholds of K9 and K2 glass after acid etching are increased by a factor of 3 and 4, respectively. Good effects are also obtained for crystal and fused silica. The strengthening mechanism of the laser-damage resistance of optical materials by chemical treatment is analyzed.

Characteristics of two-wave mixing in different BaTiO3 crystal are investigated. The results of experimental and theoretical analysis show that the energy transfer characteristics of contradirectional two-wave mixing (CTWM) is different from forward two-wave mixing (FTWM). The energy transfer direction of TWM depends not only on the orientation of the crystal c axis and the sign of the light-induced carriers, but also on the electro-optic coefficients. The experimental observation is in good agreement with theoretical analysis of CTWM in the crystal of 0°-cut type and 45°-cut type.

Referring to the principle of Landau′s theory on phase transitions, the varied transitions and critical phenomena in multi-stable optical systems are discussed. It is demonstrated that the higher the order of the multi-stability, the more varity of transitions, and shown also that the multi-stable system possesses different routes to complete mono-stability. A classification scheme of critical points corresponding to some transitions or bifurcation is made according to the stability criterion. This classification is useful to the study of critical phenomena, especially in non-equilibrium systems including the multi-stable systems.

The method of approaching the near-field diffraction patterns by sampling theorem is proposed. In the near-field diffraction, the aperture is well-defined space-function, and approximately so does the diffraction field distribution. The diffraction field can be restored with rather high precision by sampling function in its spatial spectrum. The approximate value of the spectrum bandwidth of the diffraction field is the region in which the spectrum amplitude is larger than 1% of the maximum of its center spectrum. The spatial spectrum is sampled in this bandwidth. The sampling space is proportional to the bandwidth and inversely to the space-bandwidth product of the aperture function. The calculation results of the near-field diffraction patterns of slit and circle apertures with the size smaller than the wavelength are coincided with other theoretical and experimental results. The sampling method has advantages of direct perceivable and forthright.

The local mode-coupled model is used to analyze theoretically the light field property of fiber taper in scanning near-field optical microscopy. Differential equations of the forward and backward fundamental mode fields in fiber taper are given. The backward coupling coefficient of fundamental mode is obtained numerically, and it can reach about 1% at most. The reflection makes the fiber taper act as an output mirror of tapered fiber laser resonator. It is also shown that the parabolic taper has a lower reflected coupling coefficient than the truncated taper. the experimental results of the reflection wave from fiber probe are given.

The computation method of the Gaussian optics of zoom lens with many elements of magnifying lens and many elements of compensating lens is given by using optimization calculating method. It includes almost all modes of mechanically compensated method.

Numerical modeling for CW multimode laser beams transformed by time-varying random phase plated is presented. The method is based on diffraction integral formula. The smoothing of multimode laser beams and the energy distribution dependence on the element size and time-varying speed are discussed in detial. The numerical results account for the experimental results satisfactorily.

The stimulated emission properties of a new synthesized polymer dye were reported

The color-separating multilayer systems operating in s- or p-polarization compoments used for thin film transistor-liquid crystal display (TFT-LCD) projectors have been discussed. To reduce the transmission band ripples of the dichroic filters, the designs used for s- component are emphasized. Some experimental details and measured results are discussed.

PbTiO3 ultrafine particle-stearic acid composite ultrafine film was fabricated by LB film technology,and characterized by π-A curve and atom force mircoscope. The UV-visible absorption,fluorescent and Raman spectra showed that: PbTiO3 ultrafine particle and composite LB film had quantum-size effect and dielectric confinement effect. In composite ultrathin film, PbTiO3 ultrafine particles had photo-luminescence at room temperature and their soft-mode changed.

The effects of roughness on the reflectance of soft X-ray multilayer coating are discussed experimentally and theorectically. The suitable method for analyzing the effects of roughness, and the direction of studying the roughness are presented.