An optimized Binary Optical Microlens(BOML) is designed using phase balance design method, this is an improvement on the design of Dammann′s step zone plate. The accumulating integral method is used to analyse the BOML′s diffractive result, and compared with Dammann′s zone plate. The calculated results demonstrate that the efficiency and image quality of this BOML are better than Dammann′s. The advantage of this method is that it can design the BOML with large D/F and arbitrary object and image distance.

According to the vector modal theory for any shape profile metallic grating,the diffraction fields are studied numerically. For the sinusoidal profiles and the semielliptic profile grating, the distribution of diffraction efficiency and polarization with arbitrary incident direction and Polarization are given. The effect of grating structureparameters(period, width and depth) on the diffration field is also investigated.

This paper proposes a design procedure for a new type of zone lens which may have more than-one main fool, and the locations and efficiences of these fool can be determined flexibly by designer' s requests. This design method is based on the simulated annealing optimization and provides a mean for obtaining some particular optical field distribution and may be very useful for fabrication of special zone lens.

The semi-classical model of soliton amplification in Er3+- doped fibers is established. The condition for transparent transmission in the case of distributed amplification is given. The influence caused by excited-state absorption is discussed in detail. The results obtained in this paper provides the important theoretical bases for design of Er3+-doped fiber soliton amplifiers.

In this poper, response characteristics of electro-optic modulators with polarity reversed electrode structures are analyzed and the analytic expressions of the output amplitude and phase of the modulators are derived. Numerical calculation for the bandpass frequency resPOnse of amplitude and nonlinear response of phase angle are given.

The Perturbation method is used to analyse the metal-clad single-mode optical fiber Polarizer for calculating the attenuation coefficient of Polarized fundamental modes,the extinction ratio (ER) and insertion loss (IL) of polarizers. The method is simple and can be applied to the case of fibre core partially etched off, which has not be reported before. The results of the present method agree with those of experiment.

On the base of linearly coupled mode equations, we have derived propagation constants, eigenmodes, and characteristics of power coupling for a planar coupling system consisting of four fibers with weak fusion, and fabricated the planar couplar consisting four identical fibers for the first times. The obtained experimental results about spectral responses of the coupler are in good agreement with theoritical results.

A flee electron laser oscillator with distributed feedback cavity (DFC) is developed. The theories and experiments of the Raman free electron laser (400 KeV/800 A) with DFC are Studied. The spectral measurements using a microwave grating spectrometer are presented. The narrowed spectral bandwidth covered range of 8.6～8.9 mm with central wavelength at 8 mm and output power enhancement show that oscillation happened.

The method of perturbation used for calculating the electron distribution function is discribed. The small signal gain and saturation gain of harmonic free electron laser operating in Compton region with planar undulator are obtained. Analyses and discussions on the model and results are given in this paper.

The unified-colored-noise approximation proposed by Jung and Hanggi is extended to the multi-dimensional case in this paper. Then, the Langevin equation and FokkerPlanck equation of colored cubic model for single mode dye-laser model are derived with this approximation method. The approximate formulas of the mean, variance, andskewness of the first-P8ssage-time distribution for the model are obtained and compared with the numerical simulations.

In this paper the conversion efficiency of second-harmonic generation (SHG)in the organic annular fiber is analysed based on classical electromagnetic theory. The phase matching, which can be got by the dispersion of guided modes in the annular fibers, is described in some detail. The hemicyanine annular fiber is fabricated by using LB film technique. SHG is measured by the photodetecting instrument with high sensitivity when intense 1. 06 pm pump pulses from a Q-switched YAG laser propagates through the fiber.

A new high-efficiency microstrip photoconductive switch ultrashort electric pulse generator is presented in this paper. In the ease of high voltage operation, the effect of photoconductive switch and ultrashort optical pulse upon output electric pulse of the generator is studied in theory. And the experimental results ale given.

Various photoractive crystals are used as phase filters. Theoretical analysis and experimental results are presented. The influences of different parameters on crystals which are used in phase contrast are discussed in more derail.

A Visible-to-infrared dynamic image converting system built for infrared simulation is described in this paper. It adoptS CdS-CdSe photoconductive thin-film type liquid crystal light valve (LCLV) as the key converting device. The video-rate conversion of visible image to infrared (8～12 μm) is realized. The contrast ratio of 9:1, response time of 40 ms and limiting resolution of 101p/mm have been reached.

We report on the GaAs asymmetric X-junction waveguide coupler. The mechanism of this coupler is discussed. The device is made on n-/n+ GaAs epitaxial material. The relation among the mode sorting angle and waveguide ridge height and the difference between the propagating constants of two asymmetric waveguides is analyzed by using an effective-index approximation. The device is characterized by a power division of -2.9 dB and a crosstalk ratio of less than -20 dB. It is shown that this device could be applied to switcher and optical sensor.

We theoretically analysed the relationship between the fiber dispersion and its loss for soliton propagation in the fiber with slowly deceasing dispersion, and designed the structure parameters of the fiber. Numerical results are in agreement with theoretical analysis.

This paper presents a general theoretical investigation of the crossing waveguidestructures constructed by large-size single-mode rib semiconductor waveguides. The theoretical model is based on beam propagation method and effective index method. Three kinds of structure are analysed and compared. The numerical results show that these structures exhibit similar characteristics at large crossing angles but divergences exist at small crossing angles. It is found that mode-interference dose not exist in y-junction.

In this report, the information about the initial saute of a two-level system in a cavity is supposed to have nothing by using the principle of maximal entropy. The squeezing behavior of a two-level atom interaction with the cavity field are studied. We have obtained an important result that the strong squeezing of the radiation field, when the atom stunS initially in an arbitrary statistical mixed state and initial exciting of the field is intensive enough, is close to those very much that the atom lies in a pure state initially. In the same time, the mixed-state limits of squeezing occurring are discussed.

In this paper, we discuss the influence of cavity quantum electro-dynamic (QED) effect on the fluorescence spectra of Nd- glass microspheres. The relative magnitude of the spikes and the background in spectra is analysed. The cavity QEDenhancement of spontaneous emission rate is estimated to reach 16 times.

The shock wave generation by plasma ablation is studied in this paper. The interdependent relations between various hydrodynamic parameters at the shock front and ablative flout are determined, the generation and temporal evolution of ablative shock are discussed in details.

This paper presents the experimental investigation of temperature dependences (290～380 K) of photorefractive effects in Fe:KNbO3. Results of two-wave coupling under different experimental configuration and self-pumped phase conjugstion in special Cut crystal are demonstrated.

Optical thin-films and Nd-doped phosphate glass surfaces were processed by excimer laser and CW CO2 laser pre-irradiation. Effect of laser pre-irradiation on laser induced damage threshold is investigated. The related mechanisms are analyzed.