The shape of pumping laser pulse was reshaped in fiber-garting compression of optical pulse due to the competing between self-phase-modulated and stimulated raman scattering. The salf-phase-modulated power spectra was very asymmtric. We obtained some symmtric spectra produced by salf-phase-modulated in our experiments using a 2 m single-mode polarization-preserving silicon fiber. Some characteristics of Self-Phase-Modulated power spectra are discussed.

For a general asymmetrio optical system, the Fourier transform conditions of the system are derived by using the ray matrix method. Taking account of the positioning error, the formulas for determining fraunhofer diffraction, Fourier transform and its physical focal depth region are obtained. The displacement of the spectral plane is also obtained as the incident light is of different wavefront. Two asymmetric systems as the examples are analyzed.

A new method of automatic focussing recognition and thresholding is proposed and implemented on the sysbem based on IBM/PC-XT and PCVISION plus frame grabber. The practical holograms of particle field ara analysed using this new method. The results show that the new mebhod is favorable and can be applied to automatic analysis of more general and extensive particle holograms.

Binary computer-generated interferogram——a kind of computer-generated hologram——is investigated. This kind of hologram is most suitable for synthesizing phase-only wavefront, so the discussion is within the synthesis of this kind of wavefront. The selection of object and reference waves the selection of sampling rate on the hologram are analysed. Corresponding results are presented in this paper.

An excess fraction method for calibrating optical wedge spacing with two known wavelengths is proposed in this paper. The restrictive conditions for this method are discussed and the experimental results are given.

Step approximation of refractive index has been adopted to discrete the grad'ed-index layer of GRINSOH-SQW iaser into many sublayers to obtain the eigenvalue equation of the waveguide. The effective refractive index of the fundamental mode has been calculated by using numerical method to solve the eigenvalue equation. By calculating the near-field optical intensity distribution in the direction perpendicular to the junction plane, we have calculated the optical confinement faotorr which is closely rlated to the threshold current density. Based on this, influence of the waveguide parameters on the optical confinement properties has been discussed.

The general results of two beams photorefractive oscillation of steady state in general oases is given in this paper from the dynamic equations of two beams gain oscillation. It can be used to explain the reason that the theory in reference [1,2] is out of accord anoe with experimental results. It is indicated that the theory in [1,2] is only suited to the photorefraotivo effect being pure diffusion mechanism.

Proton-exchange process causes the increase of extraordinary refractive index in 5 mol% MgO:LiNbO3 crystal, and the existence of MgO does not affect the step-like index profile of LiNbO3 proton-exchanged waveguide. Large propagation lose and instabilities of effective index are present in MgO-doped waveguides fabricated by conventional proton-exchange process, but these drawbacks can be aparently improved by post-annealing treatment.

New equations diseribing formation of space charge field are derived by taking self-diffraction and nonlinear absorption into account. It is shown that the phase mismatch of space charge field with light intensity grating plays very important role in photorefractive effect. A equation disoribing the incline and bent of eqniphase surfaces is also derived. By using/numeric al oaoulations we find the role of energy transfer in BSO. Some material parameter will affect the speed of the process, which shows the possibility of using CW laser in studying the response to temporal process.

Gaussian beam propagation through complicated optical systems is studied in detail by using matrix optics method. The results are generalized to the oases including (1) refractive indices of the object and image spaces are not the same (n1≠n2); (2) the transfer matrix elements of optical systems are complex or the element O is equal to zero. The effects of Gaissian limiting aperatore on the beam transmission are discussed. A comparison between the classical and Gaussian beam optics (n1≠n2,n1=n2) clearly illustrates their differences and relations.

This paper discusses the calculating method for theoretical limit of laser linewidth in the single mode laser cavity in which the distribution of light intensity is nonuniform. Authors analyse the revision factor of linewidth for two different models of light intensity distribution.

Space-resolved luminescence spectra of excimer laser ablation of high Tc Y-Ba -Cu-O superconducting target was studied with WP4-optioal multichannel analyzer. In the vicinity region of the target surface (d<0.35mm), a wide continuum spectrum with salf-absorption lines due to the electronic transition from the ground states of Y, Ba and Y+, Ba+ was observed. The excited state emission spectrum lines of atoms, ions and moleoulae were detected only at the distance larger than 0.35mm. These experiment results support the dynamic explanation of explosion and ejecting molecular cluster or solid fragments on laser ablation.

In this paper, we give a insight of the spectrographios properties of transmission gratings. These properties such as diffraction efficiency, line dispersion, dispersion symmetry and scattering background are seriously influenced by the grating parameters and the geometry schemes of the experiments. The discussion given here will be profitable to analysis of the experimental data.

The electric dipole radiative transition probabilities between levels nil1-nklk(ni≤5,nk≤15) for Na-like Fe have been calculated with multiconfiguration Dirac-Fock framework. We have confirmed the new regularity which has been found recently: the transition probability is just inversely proportional to the 3rd power of the principal quantum number n of upper level for a Eydberg series of spectrum lines when n is large enough.

The theoretical expressions of the distribution of temperature and photothormal deformation deflection signal in optical coatings are given in this paper. The relations between deflection signal and parameters of coating, substrate and modulation frequency are analysed by numerical calculation. The experimental resultes are compared with theoretical calculation.

In this paper some methods to suppress the rugate filter sidelobes have been discussed. It is found that rugate with good suppression of sidelobes over broad spectral regions and at the same time maintaining its stopband reflectance can be obtained by using quintio matching layers of each side and sinusoidal modulation of the remained layers.