In this paper, an Equivalent Step-Index-Fiber Method(ESFM)has been extended to multicladding fibers. Upon defining the refractive index profile for the multicladding preform, the equivalent normalized index difference for the equivalent step-index-fiber of the preform can be exactly derived by the method so that varieties of transmission parameters for the fiber drawn from the preform would be predicted conveniently. Meanwhile, cutoff wavelengths of double-cladding elliptical fibers have been calculated as an example for part confirmation. Comparision between the theory and resuls form the experiment fibers, except individual cases, shows an accuracy of 5% in predicted cutoff wavelengths. As a result, for finally determining cutoff wavelengths or fiber-drawing radii of multicladding fibers, “trial and error” between fiber-drawing and cutoff-wavelength measuring procedures can be avoided in engineering practice, saving time, energy and material.

A interferometric scheme for measuring the spatial distribution of mode coupling in high-birefringent polarization-maintaining fiber is presented. The measurement system is composed of the modulated Michelson interferometer with a low-coherent laser diode as light source. . The distribution of mode coupling points in high- birefringent fiber is determined by using the method of optic path scanning.

Based on the partial coherence theory, this paper derives the formula of intensity and variance of diffraction from a screen with randomly- distributed holes. The diffraction characteristics of the screen are analysed in detail, and the effect of spatial characteristics of the source on diffractive image is discussed. It has been shown that the light intensity distribution of diffraction field depends on geometric characteristics of the holes and the screen, and shape and size of the light source as well. This paper also shows that under certain illumination, both average intensity and variance distributions in diffraction field will not change if the number or size of definitely-shaped holes in the screen randomly changes.

In this paper we present a design for the realization of serai multi-bit full-adders by using optical bistable switches. Principle of the operation has been demonstrated with nonlinear interference filters. Experimental results of four- bit addition are also presented.

The modulating effect of a cylindrical lens on the self- imaging of a grating is investigated with Fourier spectrum analysis. It is found that periods and the position of the self-imaging of a grating are changed and the direction is rotated. The feature of the rotation is discussed.

This paper analyses time character and the main parameters of a pulsed current solenoid system for wiggler field in free-electron laser and discusses the characteristics of the solenoid wiggler field.

We have measured the surface and bulk damage thresholds as well as the multipulse accumulation effect of LN crystals. As a method of studying the damage mechanisim, nonlinear absorption process is investigated. It is found that the multiphoton absorption occurs both in bulk and surface damage processes, and is the origin of the damages. The direct reasons that result in visible damage are the stress explosion in the bulk and the thermal melting, thermal etching and plasma emission on the surface.

This paper reports the observation of the blue-green up-conversion luminescence phenomenon of HoP5O14 noncrystalline induced by pulse DCM dye laser. From the experimental measurement, theoretical analysis and calculation on the up-conversion phenomenon, mechanism and passenges, it has shown that the up- conversion luminescence of 5F3 and 5S2 level is resulted mainly from energy transfer between Ho3+ ions, and the up-conversion luminescence of 5G4and (5G3G)5level is caused by both of the sequential two- photon absorption of single H3+0 ion and energy transfer between H3+0 ions.

10 picosecond pulses from a colliding pulse mode- locked Nd : YAG laser pass through a KTP crystal and pump DMSO Raman medium. The effect of lenses with different focal length, focal point location and the length of Raman medium on the transient stimulated Raman scattering studied experimentally. Energy conversion efficiency of 45.6% and 10.5% for the forward and backward first Stokes Raman sacttering are obtained respectively. The experimental results are discussed.

In this paper, we deduced theoretically the relation between ion current and multiphoton dynamic parameters in (3+1)RMP1 process and presented a method for obtaining three-photon absorption cross section, four-photon ionization cross section and radiationless relaxation rate by RMPI technique. The dynamic parameters of Rydberg states of toluene in gas phase are experimentaly measured for the first time. The results agree with the typical expected range of magnitudes.

The spatial output character of a stimulated Brillouin scattering phase conjugate resonator (SBS-PCR) is analysed by using the ray transfer matrix theory and calculated with the aid of computer program. The profile of the transfer beam with different parameters are given. The experimental results are presented to compare with it. Some important points for design of a SBS- PCR are discussed and the different types of resonator are proposed.

In this paper a set of coupled dynamical equations for describing or stimulating common features of the increasing absorption optical bistability (IAOB) is put forward in a phenomenological way. By computers analyzing, IAOB' s dynamical characteristics have been studied.

Computer-based processing of interferogram of surface roughness measuring interferometer are introduced in the paper, in which threshold segmenting of brightness are used for binary image processing and border following for edge curve sampling.

The effect of fiber loss on the quality of soliton-effect picosecond pulse compression is analyzed by solving the modified nonlinear Schrodinger equation numerically. The results show that fiber loss affect the performance of soliton-effect pulse compressors both qualitatively and quantitatively. The compressed pulse is longer with a lower peak power and a poorer pulse quality when fiber loss is taken into account. Furthermore, the optimum fiber length for maximum compression is longer than that expected in the absence of fiber loss. The effect of fiber loss on compression quality relates not only to the initial peak power but also to the initial pulse width.

Based on the even and odd coherent states, the present paper is to construct the even and odd q-coherent states and study their important optical statistics properties (squeezing and antibunching). We have found that the squeezing may occur with the even q-coherent states but no antibunching effect. However, for the odd q-coherent states there is antibunching but no squeezing for all finite-q values.

In this paper, we have studied the dynamic of reverse saturable absorption in copper phthalocyanine (CuPc) using the rate equation theory. The experimental demostration is given by using Q-switched YAG laser and CuPc solution. The absorption cross-section of 2.6×10-17 cm2 of triplet excited state is obtained by using thereotical simulation.

This paper discussed the achromatic region, resolving power, aberration and applied range etc in orthogonal cylindrical lenses holography.

This paper describes a technique of using space filter in the light pipe uniformizer. With this filter, the uniformity of illumination of light pipe can be improved. Some parameters of the space filter are calculated and experimental results with it is given.

Raman scattering of diamond films prepared by hot filament CVD method has been measured. Raman spectra (1100-1800 cm-1) of diamond films were fitted by using a nonlinear least squares method with several lineshape functions. The best fit model was obtained which indicates that 1355 cm-1 peak for graphite D-band is an indispensable component of Raman structure of diamond films. The calculated curves agree well with the experimental Raman data. Moreover, with consideration of both graphite D-band and spatial line shape of Raman peak in diamond area can be explained. With further analysis of fitted parameters, quality of diamond crystalline and diamond content in diamond films can be shown. Good results in fitting several Raman spectra of diamond films indicate that the new fitting model is applicable.

The method and condition for obtaining pre-resonace Raman spectra by means of liquid-core optical fiber are discussed. Spectral intensity enhancement by factors of 102 to conventional sampling techniques has been measured. Pre-resonance Raman spectra of a -picolines has been observed by using 10 mW laser excitation at longer wavelengths (514.5 nm, 488.0 nm and 454.5 nm).