The characteristics of optical fibre Bragg reflective filter (FBR) are analysed on the bssis of asymmetric five- layer optical waveguuide model, and the structural parameters of FBR are discussed for broad and narrow bsnds with high reflectivity. The experimental studies on FBR are presented in this paper, including fabrication technologies and measurement method. Typical Performances of our FBR devices are as follows: 80% reflectivity and 1.5 nm bandwidth (FWHM) at 1.5μm region.

This paper deals with theoretically the complicated index profile of an anisotropic fiber with an elliptical cladding. The mathematical steps taken in our analysis include the use of a series expansion of the index profile, the treatment of integral and derivative of a delta function and an iterative technique to obtain the Green functions of the optical field. Analytical expression of leaky losses of the fiber is given. Numerical examples show that the leaky losses of a fiber with an elliptical cladding are higher than that of an anisotropic step-index fiber, lower than that of a bow-tie fiber. With eccentricity increasing a single-mode single-polarization fiber is easier to make.

This paper discusses the 3-D shape measurement using phase-shift and logical moire (PSALM) method. Several specimen have been tested. The experimental results verify that the 3-D shape contour can be measured quickly by this method and the error is less than 10%.

All-optical switching and modulation bssed on the excited-state absorption in a slice of Eosin Y aerosol by using a frequency doubled Nd: YAG pump beam and a He-Ne laser probe beam have been demonstrated. While dynamic numerical simulation using rate equation have been accomplished, which is consistent with experiments. The methods for improving characteristics of optical switching and modulation are also discussed in this paper.

In this Paper, a new kind of the nonblock four-port Banyan switching networkis proposed. Using some classical optical elementS, such as polarized prism, triangularprism, wavelength plates, and liquid crystal array polarized switch, we have demostratedit in optical experiment. 24 kinds of switching functions for the four-port Banyannetwork have been obtained.

An optical holographic associative memory utilizing a self- pumped phase conjugator and a thin piece of Ce:Fe:LiNbO3 crystal as feedback device of thresholdingand memory medium respectively is presented in this paper. The "cat" self-pumpedphase-conjugator of 16°-cut Cu: KNSBN shows rapid response and good image qualityand the thin piece of Ce: Fe: LiNbO3 crystal with low absorption coefficient has a widerange of angluar response. The complete image output can be addressed with less than 25% of stored image output can be addressed with less than 25% of stored image.

In order to lighten the heavy calculation in the optimal design of binary optical elements, the relation-shap between the number of the independent variables in the optimization and the intensity distributions of the input and/or output pictures is set up mathematically. A general optimization algorithm the ALOPEX is introduced to this area. By tubing these together, a general scheme for the optimal design of binary optical elements, which needs shorter computing time and has a strong ability of resistance to the local extrema is proposed. Some design results by using defferent algorithms are compared.

The effect of atmospheric turbulnce on the imaging quality and resolution of an optical system, illuminated by the coherent and noncoherent light, are discussed by using the information capacity and information degrees of freedom of an image imaged by the system. In the special case of the atmopheric tubulence for a coherent illumination system, there is a POtential of the superresolution beyond the classical diffraction-limit.

The evolution of laser generated plume in ambient gates was investigated using laser beam deflection technique. A XeCl excimer laser was employed to initiate the vaporization of graphite and copper targets. The information drawn from the spatially and temporally resolved deflection signals makes us to estimate the plume drifting velocities and expansion-velocities at different sarge of evolution. Also, the deflection signals showed that drifting of the laser blow-off material developed a shock wave which moves ahead of the material wave.

The spoilal inhomogeneity of plasma soft-X-ray laser medium was observed with several diagnOStic tools at reasonable and effective arrangement. The best streak lens was uSed tO Produce homogeneity laser line focused. The experimental resultS show that the plasma medium Sauce-inhomogeneity is mainly resulted from the quality of the target material and the process of focusing. In addition, The plasma X-ray emission intensities both in spatial range and time range were different notubly at different pulse lengths of the laser beam.

Doping OH-ions into NaCl crystal can improve the stability of color center efficiently. Based on X-shaped 4-mirror folded resonator, a cryogenic broad NaCl(OH-):color center laser with 1.57 μm peak wavelength and over 250 mW output has been achieved. In the poper, the stability effect of OH-ions on centers is discussed and the influential factors on color center laser oscillations are analysed.

In this paper, we devolope a method independently determining the dynamical parameters for a single mode CO2 laser through experimemtul process.

A numerical simulation method for the laser-induced temperature distrbution is presented, whieh is simple and general, without the usual limitations in analytical approaches. The dependence of temperature distribution on the material surface heat radiation, interaction time and power density of laser is analyzed. The numerical simulation results are considered to be consistent with practical cases.

The generation and compression of 1.3 μm single-mode pulses was reported for the first time. The pulses with duration of 22 ps were obtained by modulating a DCPBH-DFB laser diode with comb current pulses, and nearly transform-limited pulses were observed with compression of a G-T interferometer. The pulse-width is 9. 3 ps, the peak power is over 200 mW and the repetition is 1 GHz. The time-bandwidth product is 0.39 and the compression ratio is 2.4. The experimental resultS are discussed in this paper.

The frequenCy shift and chirp arising from the nonlinear refractive index induced by free-carrier generation in GaAs have been investigsted. A qualitatively experimental result is given out.

In this paper, a study of 1.319 μm CW Nd:YAG angel-locking laser is reported. The pulse width of less than 170 ps with repetition rates around 100 MHz and average power of 0.54 W are obtained. This kind of short pulse solid-State lasers with 1.3～1. 5 μm infrared wavelength has effective application in optic fibre commuication and transmission.

Principal refractive indices and its thermal coefficients of LiNbO3 crystal doped with 5 mol% MgO were carefully measured at the wavelengths of 0.5397 μm, 0.6328 urn, 1.0795 μm and 1.3414 μm and the temperature of 293 K, 348 K, 389 K and 428 K in the Pervious papers[1]. On the basis of measured values and modified Sellmeier's equatins, the expressions of thermal refractive index coefficients of this kind of crystal are derived in this paper. Using these expressions, the thermal refractive index coefficients in the temperature range of 293~428 K and the wavelength range of 0.5398～1.3414 μm have been calculated. It is shown that the maximum relative deviations between the calculated and experimental values is 12%. Based on the calculated value of thermal refractive index coefficient with maximum relative deviation, the noncritical phase matching temperature for 1.0795 μm is calculated to be 382.4 K, only 6 K difference with the experimental value. The expressions are useful for design of the nonlinear optical device using this kind of crystal adopted noncritical phase matching technology.

This paper studied the motion of light in nonlinear media quasiquantitively based on the optical metric model and Cartan equation. And the comparison with the traditional results are presented.

This paper describes a 4.3 m optical-infrared new technology telescope. It makes use of vacuum pipe combination of the 4.3 m telescope and 2. 16 m telecope for processing CCD imaging and optical interfering measurement. Its concentrating light power can reach to 4.8 m telescope and the resolution to that of ten matre telescope.

Based on the general analytical method of designing aspherical optical waveguide geodesic lens, the effect of rounded-edge on the curvature behavior of lens depression profile has been studied. It is pointed out that taking profile of continuous second derivative can eliminate the curvature singularity effectively and diminish the radiation loss of guided light due to waveguide bending. A new rounded-edge function has been presented by which the lens depression profile and the depth of lens can be obtained and comparison with the particular solution given by Sottini et al. is made.

The experimental observation of defleCtion of an approach monochromatic velocity atomic them using travel-wave field resonance-radiation pressure is reported and the theory analysis is Presented in this peper. In experiment, the deflection distance of the approach monochromatic velocity atomic beam is about 1.7 mm when the atomic beam interacts with a oblique incident travel-wave laser beam with detheing-100 MHz and the Δv is less than 58 m/s.

The design and experimental results of an inside-pumped miniature Nd:YAG tube laser are presented in this paper. The slope efficiency reachs 2.73%. The pulsed laser energy of 3 J has been obtained.

High energy long mode-locked pulse train in Nd: YLF laser was studied by dyamically control the cavity Q-factor. The total length of the mode-locked pulse train was about 16 μs, energy was 2.5 mJ, single stable pulse duration was 4 ps.

In this paper, we report the mode shift of Nd-glass microspherical cavity caused by small variations of cavity size. The influence of mode shift on pump coupling is analysed.

C60/C70; optical glasses; absorption spectrum