In this paper,a method,which can determine the size distribution as well asabsolute mass concentration of solid particles from the forward light flux scattered withintwo solid angles based on Fraunhofer diffraction theory,is Presented. Theoretical analysisand computer simulations are made to verify the validity and applicability of the presented method. Results show that the technique is considered to be prospective in the industrial application.

Real time investigstions on the thermal process of laser-induced damage of a Almirror and a reflectance-increasing Al mirror by photothermal displacement technique (PDT) are described. In these studies, changes of the sisnals of PDT of the damage processof Al mirror and reflectance-increasing Al mirror are observed. The mechanism of thethermal damage of Al mirrors and effect of existing dielectric films on the damage processare discussed.

Photorefractive index changes in hydrogen-loaded semanosilicate fibers under theirradiation of 193 μm light were measured using a fiber Mach-Zenhder interferometer. Experimental rsults obtained are useful for fabrication of fiber gratings and understanding ofthe photorefractive effect.

2-D velocity distribution of metal atomic vacua was measured by laser inducedfluorescence(LIF),and an average velocity distribution vs azimuth was also given.

In this paper, we have studied the all difftaction orders intensity distribution lawin a binary optical element by phasor addition and have gotten a diffraction efficiencyformula. The method is simple and the physica] picture is clear. The result may be helpfulfor well understanding diffraction intensity changes in optical elements of binary structure.

A coupling phenomenon between static and dynamic mode conversion in protonexchanged (PE) LiNbO3 waveguides, called as resonant acoustooptic coupling is reported. APreliminary and qualitative explanation of this phenomenon is presented. In addition wehave applied it to the measurements of the phase velocity of surface acoustic wave (SAW). Its variation with acoustical frequency is studied and the results are in accordance with othermeasuring methods.

In this paper, the fabrication of fiber Bragg gratings by the fourth harmonic of a Nd:YAG laser is described. This is the first report of writing with this kind of ultravioletlight source. The spatial and temporal coherence of laser team is imptoved by applying a F-P etalon and a diaphragm of small aperture. The fiber was placed in an interferometer andexposed for 60 minutes. As a result, about 3% reflection was observed at 1505 μm.

Optical limiting of 5-(2-methylthio-4-methyl-5-pyrimidinyl)-2,4 pentadiyne-1-of toplate (PDATS) with 8ns and 21 ps laser pulses at 532 μm wave engthwas reported. By employing this material with linear transmittance of 87%, low clampedoutput (Ec=180 mJ/cm2) and low threshold (Eth=150 mJ/cm2) were obtained with pspulse.

A novel compensation technique for polarization-modulated optical fiber sensors isproposed, and an optical fiber temperature sensor system is constructed. In the sensor head, a polarization beam splitter is used not only as a polarizer, but also as an analyzer,and thereflective structure is used so that the sensor head is simple, reliable and practical. Theexperimental results show that this compensation technique can stabilize the sensor outputwith a high accuracy and better long-term stability.

In this paper,a method of using a four-focus holographic lens to implement PS(Perfect Shuffle)and FPS (Folded PS) interconnection networks is proposed. The design ofthe four-focus holographic lens and the experimental results are presented.

A method to design an arbitrary-geometty(0,π)model binary phase grating isproposed after we have analyzed and compared the characteristics of all kinds of codingschemes.The development of this method can be divided into two steps:firstly,to get thehighest diffraction efficiency,we find the initial binary phase structure,secondly,we adoptan iterative method to optimize above initial structure to get expected intensity dispersion.We have designed 7 binary phase gratings to split the incident light beam into equal-intensity beams. Their diffraction efficiencies are all above 80% and their uniformity deviations are all below 0.01%, which are better than other reported results to the best of our 1< knowledge.

Thermal effects of Nd:YVO4and KTP on a laser-diode end-pumped intracavityfrequencydoubled laser was presented. The phase-retardation effects of Nd:YVO4 werehighlighted in this paper.133.6 mW of green fundamental spatial mode light have beengenerated with a "light to light" conversion efficiency of 22.1% when the incident pump power was 604.2 mW.

A type of fan axial flow CO2 laser based upon resonant silent discharge has beendeveloped successfully.Its electrodes were arc sprayed on the surface of fused silicadischarge tubes,and.the discharge was sustained by a resonant inverter tuned at about 100kHz. The sprayed electrodes proved excellent adhesion, and the belieal ones offered verygood discharge uniformity. When operated at 5 kPa gas pressured and CO2:N2:He=1:17:2 mixing ratio, the output of this laser was 225 W with 8% wall plug efficiency. The very high and low contents of N2 and He in the mixed gas made this laser different from others.

A diode-pumped, active mode-locked fiber ring laser with a repetition rate of 1~7.5 GHz is presented. The pulses of 11.7~22 ps duration,transform-limited pulses have.been generated. In addition, the laser can be efficiently tuned over the range of 1530~1570 nm.

A study of the electro-optic characteristics of azobenzene derivations waspresented,and these materials have been doped in the PVK. The electro-optic coefficient of PVK-azobenzene thin film has been measured by an electro-optic modulation method.Theelectrooptic coefficient of the PVK thin film doped with 15% (weight ratio) nitroazobenzene is as high as 13.4 pm/V. The photorefractivity was observed in anitroazobenzene doped organic composite containing polyvinylcarbazole' and a photosensitizeras well as a fullerene (C60).

The interaction of both nonequal-amplitude coupled linear-polarization solitons inanomalous dispersion region and coupled round-polarization dark solitons in normaldispersion region is numerically investigated by the split-step Fourier transformationmethod. The mechanism and the cause of the interaction are analyzed. The results show thatthe interaction of coupled solitons exists not only in the same channel, but also in the'different channel. For the latter,it is a cross interaction.

The influence of Amplified Spontaneous Emission (ASE) noise on a solitontransmission system with amplitude modulation control was analysed by means of aperturbative method. The relatively accurate result was obtained. The result showed that thecompensated gain affects the time jitter obviously.

The emission spectrum as a function of Tb3+ ion concentration in molyboenate Na5TbxEul-x(MoO4)4 has been measured at room temperature. The experimental resultsshow that fluorescence emission of Tb3+ ion at 546 nm (5D4→7F5) increases with the Xcontent. At the same time,it is observed that the energy distribution of the emissionspectrum and the luminous brightness change and a sudden change in luminous intensityappeares when x>0.7.The change of luminescence intesity can be explained by energytransfer in a radiationless resonance process between the energy levels 5D3 and 5D4 of Tb3+ ion.

The two-photon ionization spectrum of Cs atom in a strong electric field wasstudied experimentally.It was found that the core effect of Cs atom due to the higherquantum defects can affect the ionization spectrum well above the field ionization threshold,but has negligible influence on the strong field resonances near the zero field ionizationthreshold.The dependance of the strong field resonance on the polarization of the excitationlaser beam seems not fully consistent with predictions and a further study is needed.

This paper introduces a newly developed technique,which is the combination oflaser-driven gas-phase synthesis of clusters and on-line time-of-flight mass spectrometer. By using this method, carbon, silicon, carbon-silicon and nitrogen-silicon clusters wereproduced and analyzed.

The heat effect of laser-enzyme interaction was analysed by means of fractaltheory and soliton theory as well as heat conduction theory.The relation of laser radiationtime with temperature of "divide chain" or devitalization of enzyme molecule was derived too.