A beam shaper with 16 levels was designed by Y-G amplitude-phase retrieval and iteration algorithm for converting a given single-mode He-Ne laser beam into a ring-shaped intensity distribution. The ring-shaped intensity distribution is investigated experimentally and compared with the results of the computer simulation when the distance between BOE and CCD is changed. The results show a good conformity.

The key factors for successfully experiment are the optimum design of the system parameter and improved precision of fabrication, when the two-dimensional orthogonal segmented wedge array (SWA) optical system is used to generate a uniform laser focal profiles on the target with focus width of several hundred microns and a high energy utilization factor. A nine-element small-focal-spot crossed SWA system was successfully fabricated with optimum design of the system parameter and strict control precision of fabrication. The focal-spot characteristics are measured.

The wavelength conversion of 622 Mb/s and 2.5 Gb/s channels based on XGM in SOA has been successfully realized. The study on performance of up/down conversion shows that extinction ratio of up/down conversion can be effectively equalized when a SOA with gain peak wavelength longer than signal wavelength is used. So the wavelength converters based on XGM will have more applications in WDM all-optical network.

In this paper, some problems about development of the phase-shifting laser interferometer for testing power spectral density (PSD) are discussed, for example, strictly coherence of sources; the principle and method to deduce wavefront error due to stray-light fringe pattern; calibration of frequency response function for interferometer.

In this paper, a new type of resonant cavity enhanced (RCE) photodetector which divides the resonant cavity into three subcavities is proposed. The analysis shows that a narrower spectral response line-width (<1 nm) can be obtained with a high quantum efficiency up to 90%. This means that the quantum efficiency can be decoupled from both the response speed and the spectral linewidth with such a photo-detectors. This type of photo-detector may be proved useful for dense wavelength division multiplexing (DWDM) applications.

A novel sinusoidal phase-modulating (SPM) laser-diode interferometer, which can be used to measure microvibrations with a high accuracy, is reported. In this paper, the photothermal wavelength modulation of a laser diode is employed in SPM interferometer to decrease the measurement errors caused by light-intensity changes. The computer simulations and experiments verify the usefulness of the interferometer.

By means of a numerical method, it deals with the problem of the melt-threshold of semiconductors induced by CW laser beam. The melt threshold as a functions of wavelength, power and irradiating time of irradiating laser are given. The influence of the carrier effects on the temperature rise and melt threshold, the distributions of temperature and carrier concentration in the targets are also discussed.

A technique of KrF excimer laser gas alloying with pure nitrogen being employed to improve the corrosion resistance of Al/SiC metal matrix composite is reported in this paper. After excimer laser surface treatment, an aluminum nitride contained layer with a few microns thick was formed on the surface of Al/SiC MMC. In this layer, all of the CuAl2 and most of the SiC reinforcement, which were considered to accelerate the corrosion process of Al/SiC composite, were decomposed and absent. The multiple mechanism of excimer laser gas alloying is confirmed to be effective to improve the corrosion resistance of Al/SiC composite.

It is reported that the sound speed in sea water with different salinity and temperature was measured using Brillouin scattering. The measured results show that the method using Brillouin scattering is a good technique for remote sensing to the ocean.

In this paper, a improved performance of the Cr3+:LiSAF6 laser is reported. The slope efficiency is increased by 10%, when using the shotened pulse pump and matching spectrum pump transformed by organic dye. In the case of the pumping pulse duration of 120 μs and the spectrum transformed by R-640 dye, the pulse energy of 1 J at 830 nm central wavelength from 5(at-%) doped, φ6 mm×45 mm Cr3+:LiSAF6 crystal is obtained.

A narrow-pulse Q-switched tunable Cr:LiSAF laser is reported in this paper. Stable Q-switched output was obtained at 850 nm with energy of 214 mJ per pulse and pulse-width of 20 ns (FWHM) and linewidth less then 0.2 nm. The factors inducing damage of the Cr:LiSAF crystal were discussed, and a dual-wavelength tunable laser based on Cr:LiSAF is studied which can be used in DIAL (differential absorption lidar ) system.

The characteristics of the laser output for an all-solid-state LD pumped Nd:YVO4laser is studied. By taking account of the loss of cavity as a function of the Nd3+doped concentration, a new expressions of the laser output power and the slope-efficiency as a function of the doped concentration are obtained, which are coincident with the experimental results quite well. With a Nd:YVO4crystal of 0.5%, doped concentration and pumped by 5.1 W, the output power of the laser with TEM00 mode is 3.1 W, and the slope-efficiency is 71%.

A new microwave laser pumping system with high efficiency and power was discussed in this paper. The distributions of the pumping electrical field inside the one-way and cross channel microwave waveguide are calculated. The results are qualitatively coincident with the reported experiment results.

Rh-B and Pyrromethene-597 laser dyes were successfully introduced into copolymer matrices of 2-hydroxypropyl methacrylate and methyl methacrylate. The spectral properties of two copolymer dye lasers were studied in the present paper. Pumped by a second harmonic Q-switched Nd:YAG laser (532 nm), laser oscillation was achieved in the well-polished φ25 mm×25 mm cylindrical Rh-B and PM-597 copolymers without resonance mirrors. It is found that in Rh-B doped copolymer, slope efficiency and center lasing wavelength was 35.3% and 590 nm, respectively. While in PM-597 doped copolymer, 62.2% slope efficiency and 585 nm center lasing wavelength were detected. The laser damage threshold was 62.5 MW/cm2 for Rhodamine-B doped laser and 200 MW/cm2 for Pyrromethene-597 doped laser.

Based on physical model of high power laser amplifier, simulation software used to analyze laser fluence distribution and performance of amplifier was developed. The object-oriented design method is applied in the software and different laser amplifier can be simulated. By comparison with the simulated results by the other simulation softwares and experimental results of SG-ⅠⅠ laser amplifer, it can be showed that this software can simulate different laser amplifier flexibly and truly.

Coupled equations, governing variations of defining parameters of Gaussian beam propagating in logarithmically saturable nonlinear media, have been deduced from nonlinear propagational equations. Analytical soultions for coupled equations have been derived for cases where the incident Gaussian beams deviate slightly from the spatial soliton. General discussions have been made on the main characteristics of the Gaussian type breath mode formed in the nonlinear media.

The asymmetric behavior of the polarization beats in a V-type three-level system has been studied when the pump beams have either narrowband or broadband linewidth. The asymmetry is considered as a result of the drift of the zero time delay due to the dispersion of the optical components.

An azo dye-doped polymer thin film was made by a spin-coating method on single-crystal silicon substrates. The complex dielectric function and optical parameters of the film have been measured with a rotating-analysis spectroellipsometer and an absorption spectrometer. The results show that the film has a strong and broad absorption in the wavelength region of 400～600 nm, and the aggregation state of the dye molecules has a greater influence on the absorption spectrum.

Erasable optical storage on an organic m-nitrobeznal malononitrile and diamine benzene (m-NBMN/DAB) complex thin film has been demonstrated. The static optical recording characteristics were studied by the home-made static characterizer, the high contrast pattern can be produced by 780 nm laser pulses and can be erased by heating. The structural and spectral properties of the m-NBMN/DAB complex thin film were studied by the high resolution scanning electron micoscopy (HRSEM) and infrared (IR) spectroscopy.

The graphite-like film was prepared by pulsed laser deposition technique (PLD) using a KrF excimer laser (λ=248 nm). The structure of the film was investigated using X-ray Photo-electron Spectroscopy (XPS) and Raman spectroscopy, it indicates that graphite structure existes in this film. The mechanism of the field emission from the film was discussed. The emission site density of the film more than 1×105/cm2 was obtained. The experimental results indicate that the graphite-like film could be a new type of a cold cathode electronic source for use.