This paper describes a measuring system basing on an optical heterodyne interferometer, which utilizes a multi-mode laser diode and coupled optical fibers to adjust the coherent length of the system. The sensor is small and works under a non-contact condition. It is proved experimentally that this system's resolution reaches into quasi-nm, making possible the detection of the vibrating characteristics of the human ear membrane.

A method, which uses a one-dimensional array detector to measure the two-dimensional wavefront tilt of a beam, is proposed. A preliminary experiment is given to verify the principle.

A simple method to determine the refractive-index grating phase shift versus the intensity distribution pattern in a photorefractive crystal and the third-order susceptivility's phase of a nonlinear medium with a double phase conjugate interferometer is explained theoretically.

A novel system used to obtain a square focus spot has been developed, which is composed of a pair of segmented wadge arrays that are mutually perpendicular. The features of this system are that, the size of the focus spot can be varied continuously within a certain extent,the shape of the focus spot may not be influenced by the shape of the cross section of the incident beam, and the intensity distribution of the focus spot is of high uniformity and is influenced very weakly by the intensity distribution of the incident beam. In this paper, detailed theoretical analyses and numerical calculations for this system are presented.

A concept of generation of Kilovolt nanosecond pulses was experimentlly verified using a three- in- one GaAs wafer, which serves the functions of laser- cavity mirror,photoconductive switch and energy storage capacitor. The optical and electrical performances of the mentioned three elements, together with their interferance of each other, are discussed.

The optical filter is a key device used to select frequency in the FDM and high density WDM optical fiber communication systems. In this peper, a novel Bragg grating fiber filter is reported. Its transmission characteristics, width of passband, free spectral rang and fineness are analysed by a coupled-mode theory. Also, We applied the filter to the FDM-FSK system and achieved good results.

Multi- slit interference experiments have been carried out in Hefei National Synchrotron Radiation Laboratory at the X-ray water-window wavelength region using a Fresnel zone plate as a dispersion element and an aperture to reduce the linewidth.

An optical implementation of Haar wavelet transform is presented. In this method, Haar wavelet mask is prepared by thin film coating, holographic matched filters of wavelet functions are recorded in a piece of photorefractive crystal, and confocal optical systems are used as a correlator with zoom lens. A brief theoretical analysis and experimental results are given. This optical wavelet transform possesses some evident advantages, such as, simple and real- time operation, high resolution and high light efficiency, and large dada capacity.

An adaptive algorithm for controlling the chaotic optical system, termed as the neural network adaptive control algorithm in which the system identifier of the controlled chaotic optical system is a BP NN, is presented in this paper. In this NN adaptive algorithm the difference between the output of the controlled chaotic optical system and that of the trained NN identifier is employed as the negative feedback in readjusting the system's control parameter. Because the NN identifier can reconstruct the dynamics of the controlled chaotic optical system from the output time series with the support of the BP algorithm, this adaptive control algorithm is considered applied to control the chaotic optical system when the reference model for control can not be obtained in advance. The feasibility of this NN adaptive control algorithm is demonstrated with the computer simulation of identifying and then controlling a Bragg diffraction acoustooptic bistable system.

This paper presents the study of the infrared two- photon excitation visible fluorescence probing long after the UV signal stored in an opto-active material, spiropyran.Some useful information about signal writing into and reading out of such kind of storage materials was obtained.

Photonic switching nodes are important building blocks of free-space photonic switching networks. The direct control FET-SEED smart pixel (2,1,1 ) nodes (or 2×1 nodes), the direct control and embedded control FET-SEED smart pixel (2,2,2) nodes and 2×2 nodes have been designed, respectively. They may provide useful direction in making these devices.

Multiple imaging produced by a binary combined optical element of axis-off type is reported. The element having functions of splitting and focussing is combined with a two-dimensional Damman grating and a Fresnel zone plate. An imaging lens is unnecessarily needed in application. The split arrays are 9×9 and the focus length is 823 mm. When the plane of the frequency spectrum of an object coincides with the plane of the binary combined optical element, we obtain 9 × 9 multiple images of the object on the images is the same as that of the split arrays. The images are clear and uniform. The relative distribution error of the split beam intensity is less than 5%.

45# carbon sterl with a buckytube coating was modified by laser cladding and a consequent heat treatment. Rockwell hardness and the structure of the sample surface were examined with SEM and TEM. The results indicate that the surface properties of 45# carbon steel with buckytube coating are improved remarkably after medification. The average macro-hardness of the surface with optimal parameters is HRC65. At the same time, the corresion-resistance is also improved obviously.A new structure corrosion-resistant carbide as well as a great deal of polygonal crystallites which were of the order of 10 -1 micron and dispersed in a martensite matrix were observed.

A theoretical ahalysis of laser diode end-pumped intracavity frequency-doubled lasers is presented. It is shown that the output SHG power depends mainly on the pumping beam waist,cavity parameters and the round trip loss of the cavity. An experimental result of a LD pumped Nd: YVO4 laser is reported. The second-harmonic output power at 532 nm is 153.9 mW at an incident pump power of 668.7 mW, corresponding to an optical efficiency of 23%.

Parametric lasers with a turning range of 0.44～2.6 μJ have been obtained with a tlaveling-wave parametric amplifier employing BBO pumped by the second harmonic of a femtosecond Ti:sapphire laser. The highest output energy reaches 40 μJ/pulse. The tuning curve, output energy spectrum and linewidth curve vs wavelength have been measured, which are in good agreement with the calculated results.

The mechanism of a novel structure self-Q-switched erbium-doped fiber ring laser has been investigated. The results show, according to phase difference of counterpropagating light fields in a fiber loop, the optical feedback which is consisted of afiber coupler and LD chip can feedback light fields into the erbium-doped fiber selectively, and the laser can generate optical pulses with increasing amplitude. Optical pulses lead to transient gain saturation of the erbium-doped fiber, which will result in self-Q-switching in the laser. The theoretical analysis is in good agreement with the experiments.

The far field spectral distributions of ultrashort pulsed Gaussian beams are greatly influenced by space- time coupling. Because of the complex spectral distributions, thin dispersive medium will not only broaden the pulse temporal widths but also change the curves of the pulse fronts. The analytical results are supported by numerical simulations of certain pulsed beams and dispersive medium.

The time-of-flight spectra of laser induced plasma from BaTiO3 during polsed laser deposition were studied with an optical multichannel analyzer (OMA Ⅲ). The influence of the experimental conditions on the flight velocity of the ejected plasma was discussed based on the feature of their time-of-flight spectra. And it is concluded that the flight speed of the plasma depends mainly on the laser fluence incident upon the ablation target surface in the pulsed laser deposition process.

Principle, characteristics and operation of Er-doped fiber optical bistability (EDFOB) are analyzed. Low power (<10 mW) operation of EDPOB is realized using an Ar+-laser (514.5 nm). The experimental result is consistent with theory.

The main limit for a laser- guide- star adaptive- optics- system is the focal anisoplanatism. Firstly, based on the filter function of the atmospheric turbulence sensing geometry,the variance of the residual wave- front distortion resulting from focal anisoplanatism was derived, then the effective diameter d0 of the imaging system was derived. d0 was calculated according to the atmospheric turbulence model in Kunming and Xinglong. The calculation shows that the correction of the piston and the tilt is important for the adaptive optics system.

In this paper, by using the hydrodynamical model of optics and the invariant integral of the radial component E⊥ of the beam cross-section energy, we analyze the influences on the beam quality M2 factor from the wave surface distortion and from the nonuniform amplitude distribution respectively, introduce two new kinds of definitions of the beam quality, and discuss the relation among these two definitions and the M2 factor.