An approximate theory is presented which involves the broadening of propagated Gaussian pulses in single-mode optical fibers by the first-oredr dispersion. The light source is assumed to have a Lorentz spectral distribution. Formulas are derived for the ensemble average of the pulse power and the rms pulse width. The approximate expressions are quite precise in comparison with the numerical calculations with deviations between the approximate expressions and the numerical calculations smaller than 5%.

In this paper, the pressure sensitivity of an optical fiber acoustic sensor has been described theortically and its sensitivity under iohomogeneous pressure has been analyzed and evaluated. An optical fiber interferometric acoustic sensor system with DC phase tracking homedyne detection has been established. The threshold of the detectable acoustic pressure is about 200 μPa with an optical fiber 5m long.

In the paper, we analyse the effect of the sampling density on the measuring accuracy of the period of interference fringes by using a photodiode array of 1024 elements. We can get the highest measuring accuracy of about 2 × 10-5 when the sampling number of one fringe is from 10 to 80 and the sampling data quantization is 256. The loss the sampling data quantization is, the smaller the best sampling density will be.

This paper discussed an opto-heterodyne technique for small-plane-angle measurement with a frequency-stabilized longitudinal Zeeman laser as the light source. It employs the phase measuring interferometric technique. Its angle-measuring sensitivity can reach 0.002", exceeding that of the other plane-angle-measuring techniques.

In this paper, the law of radial index distribution in the lithium glass selfoc lens manufactured by one-step ion exchange technique has been analyzed. The optical distribution obtained with this method and its technical conditions have been derived. A new way of using molten salt with some Li+ and exchanging ions in more than one step has been proposed. Calculation shows that the selfoc lens manufactured with this new method has a greatly improved index distribution.

The coupling of discrete states with ionization continuum state induced by monochromatic lasers and configuration interaction was studied by means of both quasi-antoionization state appromation as well as the Fano s autoionizatum theory.

By using a Simulated model, this article established the basic heat transfer equations for laser-gas cooling systems. It can be used in the determination of heat resistance of each part in the system. Analysis indicates that increase in the circulating gas density can improve the heat transfer effect, decrease gas flow resistance and reduce power consumption. On this basis a medium pressure gas cooling system was built and succeasfuly used in a YAG laser which has a repetition rate of 10 Hz and heat dissipation power of 200 W.

NMR spectroscopy has been used for many years to investigate the structures ot glasses. NMR spectra have permitted the identification in the glasses of structorel groupings from the crystalline compounds, and the relationship of these groupings have also been determined by Krogh-Moe and Bray. According to computer calculated NMR data based on the experimental resulls in Na2O-B2O3-SiO2 system glasses, a new quantitative structural model from the principle of phase diagrams is proposed. We believe that the structiire of a simple glass resembles tire related coagrueni melting compound. A multlcomponent glass can be regarded as the melting mixtures of some nearest congrnent meliing compound in the phase diagram.

A new cavity-free optical bistable system with negative logical operating character based on aberrational self-defocusing in absorbing medium is designed. The experimental methods and results are presented, the analytical formulas for this system are given. Theoretical calculations are in good agreement with the experimental curves.

Double stimulation will cause the field to approach its initial coherent state and make its squeezing weak. There is deeper squeezing in the case of a three level cascade atom excited by one-mode field.

In this paper, we studied the characteristics of the coma of a toroid surface. A. formula for calculating the coma produced by itself is derived. Another formula for calculating the coma which accompanies the input light beam and is amplified by the toroid is also derived. Some examples are discused.

A technique for multiplexing interferometry with oriented speckle is presented. States of object at discrete time intervals can be recorded using a multislit diaphragm by this method. Any events at discrete time intervals can be studied on the same recording plane for not only the point of object surface on by one but also all-field of vision. The experimental resultes are given.

A new method for analysis and evaluation of wave fields, complex Huygens wavelet expansion, is presented, which replaces the coventional Huygens wavelet bya secondary source with complex coordinates, evaluates the field from each wavelet by complex ray theory, and superposes the individual contributions to construct the wavefield from the primary source. The method of this expansion is illustrated. In comparison with exact reference solution, the error of the method is less than 1%, provided that the expansion parameters are properly chosen.

oriented silicon is used as substrate and the surface is at an angle of 25.24° with planes. A 36 μm period diffraction grating as a mark during the anisotropic etching of silicon was generated on Si by thermal oxidation and photo-etching technology. Subsequently silicon wafers are etched in the coventional anisotropio etching solution. Continuously slanted V-groove structures on silicon have been fabricated which is used for a 36 μm groove distance blazed grating can be obtained by further reducing the groove distance.

The resonance enhancement of photoaconstic signals due to the frequency response of the photoacouatic sample cell in FTIR-PAS measurements was observed for the first time. The frequency response analysis of the cell shows that this effect originates from the unflat response of the pressure transducer of gas in the chamber. The possibility of improving the sensitivity and the S/N ratio of the photoacoustic measurements with the resonance enhancement method was discussed in this paper, and an example of using this method to analyze structure defects of SPs in the conducting polymer PTh samples was also given.

Multiphoton ionization and second harmonic generation (SHG) via two-photon forbidden 3s21S-3snp1P(n=16-21) resonance in Mg vapor have been observed and studied tn the presence of a DC electric field and were interpreted as 1-mixing of Rydberg states caused by external electric field. The experimental results are in agreement with theoretical explanation.