Chinese Journal of Lasers
Co-Editors-in-Chief
Ruxin Li
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The preparation process of a surface perturbation target on a brominated polystyrene foil was introduced in this paper. Through a laser interference process and Nickel-electroplate figure-transfer process, a Ni-plate with sine modulated perturbation figure was obtained. Taking further steps to transfer the sine perturbation figure on the brominated polystyrene foil by spin-coating, doctor-blade casting and the thermal press process were studied. The transfer-precision of sine perturbation figures on the brominated polystyrene foil was measured by SEM and an α-step apparatus. The Bromine content in the brominated polystyrene was controlled. The surface roughness on the surface perturbation target of the brominated polystyrene foil was analysed.

Jan. 01, 1900
  • Vol. 26 Issue 10 878 (1999)
  • [in Chinese], [in Chinese], [in Chinese], and Chih-Jen Sung

    N2 coherent anti-Stokes Raman spectroscopy (CARS) and H2-O2 multiplex CARS employing a single dye laser have been explored to simultaneously determine the temperature and concentrations of H2 and O2 in a premixed H2/air flat flame burner. Systematic calibrations were performed through the well-characterized flame. In particular, the temperature measurement was accomplished using the intensity ratio of the H2 S(5) and S(6) rotational lines, while the extraction of H2 and O2 concentrations was obtained from the H2 S(6) and O2 Q-branches, respectively. Details of the calibration procedure and data reduction are discussed. The associated detection limits as well as calibration errors are also identified.

    Jan. 01, 1900
  • Vol. 26 Issue 10 883 (1999)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    It is reported that by means of an electric-field poling process, a z-cut 0.5 mm thick LiNbO3 crystal with a uniform domain structure can be reliably fabricated.

    Jan. 01, 1900
  • Vol. 26 Issue 10 889 (1999)
  • [in Chinese], [in Chinese], and [in Chinese]

    It is reported that a large-bore xenon flashlamp with a quartz glass-to-tungsten inner seal has operated successfully. The airtightness and explosion energy of the lamp are satisfactory. And the basic characteristics of the lamp are similar with those of the small diameter xenon flashlamp sealed in the same way. The flashlamp is mainly used in thermonuclear fusion research as the optical pump source for solid-state lasers.

    Jan. 01, 1900
  • Vol. 26 Issue 10 893 (1999)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    An optimized design of binary phase-only matched filters used in optical pattern recognition by means of Clipping and Monte Carlo learning arithmetic in the neural network is introduced. The computer simulation result indicates that compared with the correlation output of the traditional phase-only matched filter, their signal-to-noise ratio (SNR) for recognizing output and the signal correlation peak are improved obviously. Thereby it may provide a favorable foundation for the optical implementation in the future.

    Jan. 01, 1900
  • Vol. 26 Issue 10 897 (1999)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Based on p-polarized reflectance, a novel method for measuring the optical parameters of the films coated on one side of the transparent plane plate is presented. The dependence of the reflectance ratio γ on the refractive index n, extinction coefficient k and thickness h of the films is analyzed. The γ angular modulation curves of azo-dye doped PMMA films with two incident modes was experimentally measured. By data simulation and calculating model correction, the optical parameters of the films are precisely obtained. The experimental results coincide well with the theoretical analysis.

    Jan. 01, 1900
  • Vol. 26 Issue 10 902 (1999)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A Fizeau type interferometer reported here is composed of a LD-pumped single-mode double-frequency Nd:YVO4 laser, a different-size GRIN (Gradient Index) rod lens and a 3-D fine regulation stand. It is used for the measurement of the profile, deformation and oscillatory feature of micro-surfaces simultaneously. The experimental results and theoretical analysis are given.

    Jan. 01, 1900
  • Vol. 26 Issue 10 907 (1999)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Employing a uniform density and thickness isosceles trapezoid-shaped cantilever beam, the central wavelength of the reflected wave of a fiber Bragg grating, which is pasted on the surface of the beam along the beam axis, is linearly tuned within the range of 1557.68 to 1564.2 nm experimentally. At the same time, the original uniform period fiber grating with a width of 0.52 nm (FWHM) is transformed into a chirped one which is with the maximum bandwidth of 2.52 nm and the chirp is tunable. The peak power of the reflection spectrum of the tuned grating decreases with broadening of the bandwidth.

    Jan. 01, 1900
  • Vol. 26 Issue 10 912 (1999)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Optical serial sectioning based on the depth-discriminating ability of a fiber optical confocal scanning microscope (FOCSM) can be combined with digital image processing to realize 3D microscopy. An instrument of FOCSM was designed for this purpose. In this paper, the 2D images of standard bars with some kinds of image processing in the FOCSM was shown. Furthermore, the in-focus image with the de-focus image has been compared, and the 2D images for the further 3D reconstruction are analyzed.

    Jan. 01, 1900
  • Vol. 26 Issue 10 931 (1999)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Linear chirplization of a uniform fiber Bragg grating is reported in this paper. The chirped fiber Bragg grating thus obtained has been used for standard single mode fiber dispersion compensation in an optical communication system. The principle and experimental results of the uniform fiber Bragg grating chirplization and the experimental result of chirped fiber Bragg grating dispersion compensation are presented.

    Jan. 01, 1900
  • Vol. 26 Issue 10 935 (1999)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    According to photochemistry theory, the physical processes, in which the plasma flashing destroys the hypo-class band of the high grade structure of the protein molecule and makes the structure of the protein molecule decomposed and extending and relaxing in the crystal hyaline cortex emulsification operation with the Nd:YAG laser, is proposed in this paper. The decomposed products take residual energy and agglomerate each other to form randomly the disordered and desultory structure. Thus the laser-induced delay reaction exiting in the crystal hyaline cortex emulsification operation with the Nd:YAG laser would be explained.

    Jan. 01, 1900
  • Vol. 26 Issue 10 940 (1999)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Using a Q-switched YAG laser with three frequencies, the chemical deposition of a Ni-Pd-P nano-film on the semiconductor silicon substract is obtained at ambient temperature. The test proves that the effect of the deposition by a three-wavelengths laser is better than that of a monochromatic one. The results of SEM show that the film has good selectivity. By STM analyses, the laser-induced film grows not only along the surface, but also along the perpendicular direction. The polarization curves indicate that the laser induced chemical deposition of Ni-Pd-P during a short time has high catalytic activity for the hydrogen evolution reaction (HER).

    Jan. 01, 1900
  • Vol. 26 Issue 10 943 (1999)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    In order to reduce the cracks and porosity, which always appear in the laser cladding composites of Ni superalloy and WC hard-phase, some methods were introduced in this paper: 1. uniform distribution of WC; 2. reasonable processing parameters; 3. application of a tough transition layer; 4. application of 0.1 wt-% mixed rare earth cerium; 5. laser tempering the heat-affected zone in order to obtain a tough structure. The experimental results indicate that the laser cladding coating has a uniform microscopic-structure and is free of cracks. Due to the transition layer, the micro-hardness curve of cladding is smmother than that without the soft layer.

    Jan. 01, 1900
  • Vol. 26 Issue 10 947 (1999)
  • [in Chinese], and [in Chinese]

    Welded joints of Al-Li alloy welded by YAG laser are investigated through metalloscopy, micro-hardness and electron probe micro-analysis. The results showed that a suitable welded joint can be obtained under proper welding parameters. The thoroughly penetrated thickness does not exceed 0.7 mm for the single impulse welding and 1.4 mm for the double impulse welding. The weld is narrow and has a fine grain structure while the wideness of the heat affected zone is small. Moreover, a stress releasing treatment must be done as soon as possible after welding.

    Jan. 01, 1900
  • Vol. 26 Issue 10 951 (1999)
  • [in Chinese], [in Chinese], and [in Chinese]

    In this paper, Sn-based solders have been developed and used in laser soldering of very thin titanium sheets in the atmosphere of argon. The effects of laser soldering parameters, including the types of solders and their dimensions, the laser power, the scanning rate and the diameter of the laser beam etc., on the formation of laser soldering joints have been investigated.

    Jan. 01, 1900
  • Vol. 26 Issue 10 955 (1999)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    With different doping levels of Yb3+ in the Yb:YAG crystal, an efficient room-temperature Yb:YAG thin chip laser operating at 1.053 μm pumped by a Ti:sapphire laser was realized. For a 20 at-% Yb:YAG thin chip (6 mm×6 mm×0.5 mm), a 356 mW output power was obtained for an absorbed pump power of 784 mW, and an output coupler transmittivity of 4.26%, giving a slope efficiency of as high as 69% and an extrapolated threshold of 275 mW. The experimental set-up of the thin chip laser is described.

    Jan. 01, 1900
  • Vol. 26 Issue 10 865 (1999)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A Ti:sapphire regenerative amplifier developed recently as a key part of the whole on-developing table-top TW laser system is reported. Experimentally, its energy and temporal performance under the condition of free-running is investigated: the slope efficiency of 10% and the output pulse energy as high as 4 mJ are achieved under a pumping energy of 45 mJ; The build-up time of the output laser pulse is steadily 350 ns and its repetition rate is 10 Hz. From these indexes it shows that the cavity structure and the optical setup of the regenerative amplifier are good and its steady operation makes the injection and amplification of the seed pulse reliable.

    Jan. 01, 1900
  • Vol. 26 Issue 10 869 (1999)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    With the MPC circuit power losses on the thyratron reduced, an increase of the tube lifetime and input power is realized. So, the laser output power is increased. The stability of the laser operation is improved. A small magnetic pulse compressor which is made of a ZnNi magnetic core works in the CVL circuit successfully. A theoretical consideration of the MPC is presented and the experimental results are analysed.

    Jan. 01, 1900
  • Vol. 26 Issue 10 873 (1999)
  • [in Chinese], [in Chinese], and [in Chinese]

    An analytic expression of the self-phase modulation induced by chirp in non-Kerr-like optical fibers with saturable nonlinearity is derived taking into account the fiber loss. The evolution of chirp is simulated by computer. The results show that the more powerful the saturable effects, the smaller the chirp induced by self-phase modulation; the chirp increases in magnitude with the propagation distance and the chirp depends on the fiber loss and the peak power of the incident pulse.

    Jan. 01, 1900
  • Vol. 26 Issue 10 917 (1999)
  • [in Chinese], [in Chinese], and [in Chinese]

    The effect of the additive coloured noise on mode-competition of a two-mode laser is studied. By means of a linear stability analysis, considering τ as a small parameter, some conclusions have been obtained. In strong coupling, the effect of the additive colored noise on mode-competition is stronger than that of the additive white noise, and increases with the increasing of noise strength. In weak coupling, the effect of the additive colored noise on mode-competition is weaker than that of the additive white noise, and decreases with the increasing of coupling constants.

    Jan. 01, 1900
  • Vol. 26 Issue 10 922 (1999)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The stimulated diffuse band radiation of molecular potassium generated by the energy-polling effect is reported. The generation mechanism of the diffuse band radiation and the appearance of the atomic trapping effect are discussed.

    Jan. 01, 1900
  • Vol. 26 Issue 10 927 (1999)
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