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

128×128 element GaAs microlenses array is fabricated by a new method, named curvature inversion method. Scanning electron microscope (SEM) shows that microlenses have distinct spherical and concave contour, and surface stylus measurement shows that the concave microlenses array has smooth surface and its elements are of same size. For the concave microlenses array, the depth of concave spherical surface is 1.268 μm, the focal length is -352.04 μm.

Jan. 01, 1900
  • Vol. 28 Issue 6 530 (2001)
  • [in Chinese], [in Chinese], and [in Chinese]

    Based on the combined transformation theory of the space coordinates, a scheme, which introduces three non co-linear marked points in the public areas of the adjacent subdivided shapes to digitize the whole profile, is proposed. The blending accuracy of the result data is analyzed and a verification about this is done in light-sectioning measurement system. Experimental results show that this approach can realize the subdivided shapes measuring and data registering as the features of rapid speed, high accuracy and simple operation in optical three dimensional profilometry.

    Jan. 01, 1900
  • Vol. 28 Issue 6 533 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Based on laser interference and processing digital image technology and the FFT method, this paper has discussed the questions about analyzing and solving automatic measurement of gauge block central length, and correcting the measurement result by ambient parameters.

    Jan. 01, 1900
  • Vol. 28 Issue 6 537 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The diffuse reflectance and transmittance of human arteries and veins were studied with 632.8 nm of He-Ne laser. The measurements were performed with two standard integrating sphere systems. The absorption coefficient, scattering coefficient and the changes of total optical intensities I(x), forward scattering flux i(x), backward scattering flux j(x) as a function of thickness of human arteries and veins were evaluated and analyzed from the experimented data by Kubelka-Munk model. The results of measurement showed significant difference of diffuse reflectance and transmittance between arteries and veins at 632.8 nm wavelength of He-Ne laser. Furthermore, the absorption coefficient and the scattering coefficient of arteries were obviously bigger than that of veins at He-Ne laser wavelength. The changes of I(x), i(x) and j(x) as a function of thickness of human arteries and veins were also significant difference.

    Jan. 01, 1900
  • Vol. 28 Issue 6 573 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A new method of making computer-generated hologram (CGH) by electron-beam direct-writing is reported in this paper. Compared with conventional CGH fabricating method, the new method can improve the image quality of CGH obviously. In this paper, the comparative experimental results of two methods are given, and the effects of quantizing and coding errors on the signal-to-noise ratio of CGH are also analyzed theoretically.

    Jan. 01, 1900
  • Vol. 28 Issue 6 556 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A pseudo color codingfractional Fourier transform rainbow hologram is presented in this paper. Based on itscharacteristics that the coding color relates not only to the position of slit, but alsoto the fractional order of recording and reconstruction system, a new anti-counterfeitingholography is established.

    Jan. 01, 1900
  • Vol. 28 Issue 6 559 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    In the paper newalgorithm to remove most noise with adaptive filter on image pixels areas of receivingport is proposed. It is composed of selecting part window, statistics analysis,least-squares-multiplication and so on. The visual quality of infrared image can beimproved clearly by this way.

    Jan. 01, 1900
  • Vol. 28 Issue 6 562 (2001)
  • [in Chinese], [in Chinese], and [in Chinese]

    In order to improve the precision and efficiency of teach-and-play-back programming for laser machining, and overcome the structural limitation and the manual deficiency of the old system, a programming system is presented by adopting the concept of borrowed-machine measurement to integrate the laser scanning measuring probe and the CNC system. Here's the key technology to change the measurement of surface normal vector of machined surface into the measurement of points. And, it also addresses the measurement of free-form trajectory on 3-dimension surface in detail.

    Jan. 01, 1900
  • Vol. 28 Issue 6 565 (2001)
  • [in Chinese], [in Chinese], and [in Chinese]

    It presents thepreparation of ferroelectric Pb(Zr,Ti)O3 (PZT) thin films by pulsed laserablation deposition technique in the article. The substrate was single crystal Si(100) andthe pulse laser beam was Nd:YAG laser with wavelength of 532 nm and frequency of 5 Hz. Themicrostructures and micrographs of deposited PZT thin films were studied by X-raydiffraction (XRD) and scanning electron microscopy (SEM), respectively. The evolution ofmicrostructure and micrograph with the variation of substrate temperature was given. Theeffect of substrate temperature on preparation of PZT thin films was discussed on twopoints. One is the chemical reactions of laser ablations with the mixture induced byenergy release with the contribution of epitaxial stress, intrinsic stress and thermalstress as well as phase transformation stress.

    Jan. 01, 1900
  • Vol. 28 Issue 6 570 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The rate equationsincluding Nd:phosphate glass medium gain, Cr4+:YAG passive Q-switch slowsaturation absorber and parameter of resonator have been built up. The calculated outputpulse profiles from the Q-switched oscillator and the three-pass amplifier are given. Thecalculation results have been compared with the experimental data showing a goodconsistence.

    Jan. 01, 1900
  • Vol. 28 Issue 6 481 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    By using LD as a pumpingsource, the self-Q-switched laser of Cr,Nd:YAG crystal is demonstrated. The output Q-switched traces are verystable. The threshold pumping power is 3.5 W and pulse duration is 50 ns. The slopeefficiency is as high as 20%. When the input power is 10.8 W, 1.46 W self-Q-switched laserat 1064 nm is obtained. The pulse width keeps nearly constant and pulse repetition ratevaries with the variation of the pumping power.

    Jan. 01, 1900
  • Vol. 28 Issue 6 484 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    In this paper, themethod of making passive Q-switching laser by using a saturable absorber Cr4+:YAG is improved. With putting alens in the laser cavity, the characteristics of the laser such as peak power, pulse widthare changed. The output pulse shape becomes smoothly. Those characteristics are discussedtheoretically.

    Jan. 01, 1900
  • Vol. 28 Issue 6 487 (2001)
  • [in Chinese], and [in Chinese]

    Utilizing SHG tunablefeature of nonlinear crystal BBO, an experiment of UV tunable laser in 200~350 nm with conversion efficiencyfrom 15.3% to 23.6% has been demonstrated. The influence of the divergence angle and thelinewidth of the incident parametric light on the SHG conversion is calculated andcompared with the experiments.

    Jan. 01, 1900
  • Vol. 28 Issue 6 491 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    High power semiconductorlaser stack arrays, grown by MBE have been prepared. The epitaxial structure for LD is anoptimized SQW GRIN SCH structure, and cm bars are made with a fill factor of 60%. A LDstack assembly with water cooling is formed to obtain an effective heat delivery ability.The following results are preliminarily obtained: Ith of the stack lasers is 12A, CW output power can reach to 40 W at 30 A; FWHM of the lasing spectrum is 6 nm with acentral wavelength of 810 nm, and the slope efficiency (ηs) is 2.2 W/A.

    Jan. 01, 1900
  • Vol. 28 Issue 6 494 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    1.3 μm InGaAsP laser diodes are widelyused in optical fiber transference system. In order to expand the application in otherfields, the effect of electron radiation of 1.3 μm InGaAsP laser diodes is studied. The results show thatfor the energy of electron ranges from 0.4 MeV to 1.8 MeV, the fluence of 1×1015cm-2 is a critical point, beyond which, the laser diodes are damaged. The Y2O3-ZrO2coatings are valuable to the la ser diodes for radiation protection.

    Jan. 01, 1900
  • Vol. 28 Issue 6 497 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A theoritical model ofthe multiple-pass cavity for a femosecond Ti:Al2O3 laser with low repitition rates and high peak intensities isimproved. The cavity stability and the zero effective length are calculated and analyzed.

    Jan. 01, 1900
  • Vol. 28 Issue 6 501 (2001)
  • [in Chinese], [in Chinese], and [in Chinese]

    In this paper, anelectrooptically Q-switched RF excited CO2 waveguide line-selected laser withtunable output is demonstrated. Peak power, setup time and pulse width of the laser pulsescan be tuned by adjusting the electrical voltage on the crystal. Theoretical andexperimental results are consistent. A simplified construction is proposed to improve thelaser output power.

    Jan. 01, 1900
  • Vol. 28 Issue 6 505 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    This paper discusses thedesign of full-inner-cavity birefringence dual-frequency He-Ne laser with fixedfrequency-difference by angle-block structure, and the frequency-stabilization schemes ofserving the laser with heater through the equal light intensity methods. The frequencystability is better than 2×10-7 within 8 hours.

    Jan. 01, 1900
  • Vol. 28 Issue 6 509 (2001)
  • [in Chinese]

    Detailed analysis of thelaser beam distribution after passed optical system is significant to the deep study theinteraction of laser beam and material. In this paper, the diffraction of randomdistribution laser beam passing through an optical system has been analyzed in detail, andan industrial application laser beam transformation system has been given.

    Jan. 01, 1900
  • Vol. 28 Issue 6 513 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Considering the wave number dependence of the waist size in laser resonator, the exact intensity solution of the pulse through achromat is obtained. The effect of group velocity dispersion (GVD) on the focus was discussed. The influence of lens dispersion up to second order on the spatial and temporal intensity distribution of the femtosecond Gaussian beam was analyzed. The influence of input beam size on the maximum intensity in the focus of singlet lens and achromat was compared.

    Jan. 01, 1900
  • Vol. 28 Issue 6 518 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    In this paper,energy-pooling collision process of atomic sodium assisted argon atoms is reported. Thestimulation radiation of violet region for the atomic sodium and sodium dimer of tripletstate were observed. The experiment results showed that the angle momentum plays an rolein the population process of high-lying states. The experiment results were fitted withtemporal rate equation.

    Jan. 01, 1900
  • Vol. 28 Issue 6 523 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Influence ofelectro-oxidation of ascorbic acid was investigated under CW laser irradiation. It wasfound that oxide current dramatically increased and initial oxide potential evidentlydecreased with laser irradiation. The current increased by 5.71, 2.14, 3.02 times for GCE,graphite electrode and Au electrode, respectively. Initial oxide potential decreased by 50mV for both GCE and graphite electrode, by 250 mV for Au electrode. The thermal effectproceed by laser irradiation is mainly factor to cause the changes of oxide current andpotential, at the same time, electrode surface is likely activated to a certain extent dueto laser irradiation accelerating electrode reaction.

    Jan. 01, 1900
  • Vol. 28 Issue 6 527 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The acousto-optical mode conversion effeciency, filtering bandwidth and wavelength tuning range of the acousto-optical tunable fiters (AOTF) based on single mode (SM) fiber are analyzed theoretically. A fiber AOTF with <0.1 dB insertion loss, <1 nm bandwidth and >30 nm tuning range is realized experimentally.

    Jan. 01, 1900
  • Vol. 28 Issue 6 541 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    According to the simplified system model, the converted signal chirp of all optical wavelength converter based on cross-gain modulation in semiconductor optical amplifier is explored in detail. The influence of the signal power, probe power, signal pulse width and pump current on the chirp is simulated. The chirp dependence on the signal pattern is analyzed.

    Jan. 01, 1900
  • Vol. 28 Issue 6 545 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The performance of all-optical wavelength converter based on the gain saturation effect in fiber grating external cavity LD is investigated. In order to eliminated the influence of the returned light and converted output light on the input signal source, and to increase coupling efficiency of input signal and output signal, a new optical scheme of converter using optical circulator are proposed. The experiment results show that wavelength conversion range is over 30 nm, and both up- and down-conversion are realized. Dynamic wavelength conversion for 155 Mbit/s NRZ input signal is presented.

    Jan. 01, 1900
  • Vol. 28 Issue 6 549 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The EDFA gain flattening equalizer using a long period fiber gratings (LPGs) fabricated using amplitude mask scanned by UV light is presented in this paper. The results show that this EDFA is flat to within ±0.4 dB exceeding 30nm usable bandwith.

    Jan. 01, 1900
  • Vol. 28 Issue 6 553 (2001)
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