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

The characteristics of fiber acousto optic coupled ring resonators were studied. It is found that a novel acousto optic coupled ring resonator can be got for the frequency shift and filtering characteristics of the acousto optic fiber coupler. Theory and experiments have demonstrated that such a resonator has a unique feature that it can convert continuous laser to pulse train caused by the interference of multiple beams with accumulative shift frequencies in the fiber loop.

Jan. 01, 1900
  • Vol. 30 Issue 4 325 (2003)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The physical mechanism of green laser inducing erythrocyte fluorescence spectra in vitro is analyzed by a model of non syntonic dipole in this paper. The theoretical investigation shows that while the erythrocyte from blood is radiated by a low lever frequency doubled Nd∶YAG laser with wavelength 532 nm, anisomerous C-C bonds or C-N bonds on membrane of the erythrocyte would absorb the energy by non resonance and be parted to produce lone pairs of electrons. The new fluorophores from the lone pairs of electrons under the laser excitation would emit fluorescence. It may supply some references to the explanation the mechanism of low level laser irradiating blood therapy in vivo.

    Jan. 01, 1900
  • Vol. 30 Issue 4 369 (2003)
  • [in Chinese], [in Chinese], and [in Chinese]

    Measurements of total reflectance and transmittance for porcine nasopharyngeal tissue using single integrating sphere technique were carried out under the irradiation of He Ne laser at the wavelength of 632 8 nm, which has the advantage over conventional double sphere techniques in that no corrections are required for sphere properties. Furthermore, with the measurement of collimated transmission for optically thin slabs, the optical properties of porcine nasopharyngeal tissue in vitro were indirectly obtained by applying inverse adding doubling theoretical model. The optical properties of porcine nasopharyngeal tissue are characterized by low absorption and high scatter, and the value for absorption coefficient and scattering coefficient are 0 96 cm -1 and 62 7 cm -1 , respectively. The scattered light is highly forward as demonstrated by the mean cosine of the scattering angle, and the optical penetration depth for porcine nasopharyngeal tissue is about 0 241 cm.

    Jan. 01, 1900
  • Vol. 30 Issue 4 373 (2003)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Instead of cumbersome standard calibration chart method , this paper applied ray tracing method to analyze the formation of angioscope image distortion, developed a polynomial correction formula, and successfully realized the correction of angioscope image distortion.

    Jan. 01, 1900
  • Vol. 30 Issue 4 377 (2003)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The characteristics of an acousto optic tunable filter and its optical system are investigated. The effective solutions to improve the purity of the diffracted light in this optical system are put forward. The orthogonal polarizing method, and the combined modulation method of optics and electronics are discussed. The measurement results of several optical improvement methods are compared with that of FT IR through the near infrared spectral measurement of water. The results show that both methods can effectively reject the inference of zero order light. But the orthogonal polarizing method does at the expense of the utilization ratio of light. The combined modulation method can increase spectral resolution and signal to noise ratio of this optical system, while not decrease the utilization ratio of light.

    Jan. 01, 1900
  • Vol. 30 Issue 4 329 (2003)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Considering the different physical properties between the tumor and the surrounding normal tissue, a two layer model was developed to describe the energy transport and the temperature behavior in the tumor tissue during the laser induced interstitial thermotherapy (LITT). Photon transport was simulated with the Monte Carlo method and then energy distribution was used to calculate the temperature distribution with Pennes bio heat equation. Both the time required to coagulate the tumor and the thermal damage depth are numerically predicted.

    Jan. 01, 1900
  • Vol. 30 Issue 4 380 (2003)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Ni/WC composite coatings were prepared on A3 steel by laser cladding. The morphology and distribution of WC particles under the different laser power and their influences on the wear resistance properties were studied. The results showed that under the appropriate laser power WC particles partially dissolved, with the epitaxially grown needle like carbide around them. Undissolved WC particles are combined strongly with the coating matrix, which has improved wear resistance when compared with the Ni based alloy coating.

    Jan. 01, 1900
  • Vol. 30 Issue 4 357 (2003)
  • [in Chinese], and [in Chinese]

    A novel technology by using laser microband antenna on curved surface of teflon, polyimide and epoxide resins is introduced in this paper.

    Jan. 01, 1900
  • Vol. 30 Issue 4 361 (2003)
  • [in Chinese], and [in Chinese]

    According to the characteristic of laser intelligent manufacturing system, a method of trace generation for the 5 axis laser robot is introduced. A parameterized spatial surface has been constructed from 3 dimensional scattered data, and upon it the 5 axis trace for laser processing can be laid out. Practical experiments demonstrated that satisfied results were acquired by using the method, which has been applied in laser intelligent manufacturing system.

    Jan. 01, 1900
  • Vol. 30 Issue 4 364 (2003)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    This paper analyzes the principle of wavefront disturbed by the free vortex aerodynamic window(FADW) designed for the high power laser measurement using the Hartmann Shack (H S) sensing, and measures the wavefront when the FADW is running steadily using the H S sensor with 37 sub apertures experimentally. The wavefront attained by CCD detectors is sent to the high speed DSP wavefront processing units. And then it reconstructs the disturbed wavefront using the method of Zernike mode, and calculates the relative optical parameters such as the peak value (PV) of wavefront error, RMS and STREHL raton (R s) and so on.The results shows that the effects on the output laser wavefront of the FADW are mainly the beam deflexion and the beam divergence, otherwise the else high level wavefront errors are very low.

    Jan. 01, 1900
  • Vol. 30 Issue 4 289 (2003)
  • [in Chinese], [in Chinese], and [in Chinese]

    Numerical simulation and performance analysis of flow fields in hypersonic low temperature (HYLTE) nozzle and optical cavity of a small continuous wave (CW) DF chemical laser, which employed a single throat HYLTE nozzle (STL), under different stagnation and structural parameters have been carried into execution to interprete the disparity between device design and experiment. Distribution of F atom mass fraction, static pressure and static temperature in cold flow field has been analyzed. Distribution of small signal gain in reactive flow field also has been simulated and qualitatively compared with spots ablated from organic glass. Some orientations have been conformed to improve the performance of the STL DF laser.

    Jan. 01, 1900
  • Vol. 30 Issue 4 295 (2003)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    This paper proposed a method to compensate the wavelength change of Yb doped fiber laser caused by temperature variation by controling the dielectric reflector position.

    Jan. 01, 1900
  • Vol. 30 Issue 4 300 (2003)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Experiment study of dynamics characteristic of D shape inner cladding Yb 3+ doped fiber laser is presented. The fiber laser in one mirror and two mirror cavity is pumped by a multi mode laser diodes. Self pulsing regimes are obtained in one mirror cavity. The Brillouin pulses appear with the increasing of pump power. The pulse duration is as short as 10 ns. The self pulses are suppressed in the two mirror cavity. In this case the stability of the laser is improved, and the threshold of the laser decreases.

    Jan. 01, 1900
  • Vol. 30 Issue 4 303 (2003)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    In this paper, polymerization of acrylic acid was induced by excimer laser (248 nm). The molecular weights of polymers of acrylic acid were measured by GPC gelatin chromatogram. The rule of polymerization of acrylic acid was also explored. The results of experiments show that the polymerization is a kind of radical induced polymerization adding H 2O 2 as photo initator. In the experiments, the molecular weights of polyacrylic acid can be increased when the concentration of acrylic acid solution is diluted; the laser irradiating time decrease and the power of each pulse increases.

    Jan. 01, 1900
  • Vol. 30 Issue 4 307 (2003)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Based on the chaotic theory, the conditions to avoid chaotic phenomena in fiber lasers are achieved. The chaotic phenomena occurred in the experiment. By adjusting the fiber laser according to the conclusion of this analysis the chaotic phenomena disappeared finally.

    Jan. 01, 1900
  • Vol. 30 Issue 4 311 (2003)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The accurate expressions of effective nonlinear coefficient, phase mismatching gradient and acceptance angle were achieved by means of theoretical analysis of Noncollinear phase matching in uniaxial crystals. For example the theoretic calculation and relevant experiments of noncollinear SHG in KDP crystal were made.

    Jan. 01, 1900
  • Vol. 30 Issue 4 315 (2003)
  • [in Chinese], and [in Chinese]

    Based on single mode laser system, a new dynamical system under external periodic perturbation modulation is constructed and investigated by using of the numerical analysis method. The results show that the perturbation amplitude (PA) is control parameter of the system, the state of the system takes on 2 np oscillation patterns as the PA is in different numberical regions.

    Jan. 01, 1900
  • Vol. 30 Issue 4 322 (2003)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A numerical simulation study on field of temperature in crystal and melt by using FDM (Finite Differential Method) during the growth of Nd∶YAG crystal by Cz (Czochralski) method was reported. At first, the mathematical model of the growth of Nd∶YAG crystal was given, then the equations with no dimensions were given. Finally, the boundary condition was given and the equations were solved by FDM. The simulation program was given by above method, and then the change of field of temperature in crystal and melt was described by simulation program. The effect of technological conditions on field of temperature in crystal and melt was analyzed.

    Jan. 01, 1900
  • Vol. 30 Issue 4 334 (2003)
  • [in Chinese], [in Chinese], and [in Chinese]

    A new cyanine film has been developed by means of spin coating for digital versatile disc recordable, The absorption spectrum and the complex refractive index of the cyanine thin film were measured, The absorption and reflection properties of the sublimated cyanine film are pretty good at 630~650 nm. The fabricated DVD R disc has been tested on the static, dynamical optical recording units at the wavelength 632.8 nm and on the DVD RT650 tester at the wavelength 650 nm. The results of testing show DVD R discs made of the cyanine dye have good optical recording performance.

    Jan. 01, 1900
  • Vol. 30 Issue 4 341 (2003)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    ZrO 2 thin films were deposited on Pt/Ti/SiO 2/Si and SiO 2/Si substrates by pulsed laser deposition (PLD), respectively. Spreading resistance profile (SRP) was used to study the resistivity distribution across the ZrO 2 thin films. The relations between the crystal structure and substrate temperature were tested, using X ray diffraction (XRD). The surface roughness of ZrO 2 thin films is measured accurately and the influence of the crystal structure of the ZrO 2 thin films on their electrical I-V characteristics is birefly discussed.

    Jan. 01, 1900
  • Vol. 30 Issue 4 345 (2003)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The effect of polarization mode dispersion (PMD) on the spectrum of received signal is theoretically analyzed and proved by experiment. A method for automatic PMD compensation in 10Gbit/s fiber optic communication system and its experimental result are presented. The results indicated that it is effective for first order PMD compensation.

    Jan. 01, 1900
  • Vol. 30 Issue 4 349 (2003)
  • [in Chinese], [in Chinese], and [in Chinese]

    Encoder and decoder for optical code division multiple access is the key technique of the realization of optical code division multiple access communication system. A tunable serial encoder/decoder for optical code division multiple accesses is presented. Fundamental is analyzed, optimal parameters for designing it are derived, and function simulation is done. The encoder/decoder features that encoding/decoding is done serially, address codes can be tunable, encoder and decoder can be in one unit and it not only can be used in synchronous optical CDMA system but also can be used in asynchronous optical CDMA system. Therfore, it possesses some degree of practical value.

    Jan. 01, 1900
  • Vol. 30 Issue 4 353 (2003)
  • Please enter the answer below before you can view the full text.
    Submit