Journals >Chinese Journal of Lasers
Contents
1986
Volume: 13 Issue 11
17 Article(s)
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Laser Devices and Laser Physics
Effects of injection in free-electron lasers on axial velocity spread of beams
Wang Yuandian
An electron beam can be injected into the interaction region of a free-electron laser adiabatically or non-adiabatically. Non-adiabatic injection can induce axial velocity fluctuations, therefore adiabatic injection is preferred. For free-electron lasers with axial magnetic fields, initial perpendicular velocities can An electron beam can be injected into the interaction region of a free-electron laser adiabatically or non-adiabatically. Non-adiabatic injection can induce axial velocity fluctuations, therefore adiabatic injection is preferred. For free-electron lasers with axial magnetic fields, initial perpendicular velocities can induce axial velocity fluctuation too. In order to reduce the fluctuation amplitude, a step-like axial magnetic field can be applied for cooling perpendicular temperature of the beam, and proper selection of system parameters is necessary..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 671 (1986)
Influence of reaction and ralaxation rate coefficients on gain characteristics in HF chemical lasers
Chen Liyin, and Zhou Xuehua
The effects of different velocity ratios of two parallel gas flow and the uncertainty of kinetic rate coefficients on the characteristcs of HF chemical lases are investigated. It is shown that the collisional relaxation process of HF(v)-H is so fast that the variation of its rate coefficient have significant influence The effects of different velocity ratios of two parallel gas flow and the uncertainty of kinetic rate coefficients on the characteristcs of HF chemical lases are investigated. It is shown that the collisional relaxation process of HF(v)-H is so fast that the variation of its rate coefficient have significant influence on the gain characteristics..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 675 (1986)
An XeCl excimer laser with magnetic compressor
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The characteristics of an XeCl excimer laser using magnetically assisted switch techniques were investigated. The pulse rise time discharge current was compressed from 200ns to 50ns, and the amplitude of reversal current was reduced extraordinarily. These results are in good agreement with theoretical calculated ones. The characteristics of an XeCl excimer laser using magnetically assisted switch techniques were investigated. The pulse rise time discharge current was compressed from 200ns to 50ns, and the amplitude of reversal current was reduced extraordinarily. These results are in good agreement with theoretical calculated ones. The effects of by-pass inductance on the compression were discussed..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 683 (1986)
Experimental study of unstable cavity injection mode-locked TEM-CO2 laser
Xu Huale, Yi Jingrong, and Cai Yingshi
AN unstable cavity injection mode-looked TEA-CO2 laser with 1 m long gain medium is described. It can operate in single longitudinal mode without adjusting cavity length, Under some conditions injection mode-looking happens even two lasers individually oscillate in different brancies.AN unstable cavity injection mode-looked TEA-CO2 laser with 1 m long gain medium is described. It can operate in single longitudinal mode without adjusting cavity length, Under some conditions injection mode-looking happens even two lasers individually oscillate in different brancies..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 687 (1986)
“Keyhole” mechanism in welding thin plates with a low power CO2 laser
Pu Wanlin, Xiao Min, and Cheng Zhutao
A new effect was discovered in welding thin metal plates with a low power CO2 laser. In the welding process, a small hole exists in the welding puddle and penetrates the plate. This effect was proved experimentally for the first time The conditions of power and energy density were also investigated experimentally and tA new effect was discovered in welding thin metal plates with a low power CO2 laser. In the welding process, a small hole exists in the welding puddle and penetrates the plate. This effect was proved experimentally for the first time The conditions of power and energy density were also investigated experimentally and theoretically..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 690 (1986)
A new exciting method for optical fiber measurement
Shi Zhengdong, and Shi Qinling
This paper analyses some typical exciting conditions in optical fiber measurement and proposes a new equilibrium mode distribution method, in which a "S. S. F." mode stripper is used to improve greatly the measurement accuracy of the fiber loss. It provides an effective and reliable exciting method for accuraThis paper analyses some typical exciting conditions in optical fiber measurement and proposes a new equilibrium mode distribution method, in which a "S. S. F." mode stripper is used to improve greatly the measurement accuracy of the fiber loss. It provides an effective and reliable exciting method for accurate measurement of optical fiber parameters..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 695 (1986)
Holographic technique used in phase difference amplification
Qi Zhang fen, Chen Jianwen, Zhang Dake, and Fu Shufen
A method for eliminating wavefront aberration, used in phase difference amplification was proposed. Two holograms were inserted in two optical paths of a Mach-Zehnder interferometer respectively. One of the holograms recorded the information of both object phase and wave-front aberration of the system, the other recordA method for eliminating wavefront aberration, used in phase difference amplification was proposed. Two holograms were inserted in two optical paths of a Mach-Zehnder interferometer respectively. One of the holograms recorded the information of both object phase and wave-front aberration of the system, the other recorded only that of wavefront abarration. While reconstructing, the wayefront abarratioa could be eliminated and the amplified phase difference obtained. The experimental results were given finally..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 699 (1986)
Excimer laser induced reaction of graphite with hydrogen
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Irradiating graphite in hydrogen atmosphere with XeCl excinier laser light, some hydrocarbons, i. e. CH4, C2H2, C2H4 and C2H6, were formed. The possible mechanism was discussed.Irradiating graphite in hydrogen atmosphere with XeCl excinier laser light, some hydrocarbons, i. e. CH4, C2H2, C2H4 and C2H6, were formed. The possible mechanism was discussed..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 704 (1986)
Growth and measurement of GGG(Ca, Mg, Zr): (Nd, Cr) laser crystals
Xun Damin, Zhu Huanan, Jin Fuhui, Liu Hairun, and Zhang Lehui
Gadolium gallium garnet crystals substituted with Ca,Mg, and Zr and doubly-doped with Nd and Cr are grown, and their laser properties are investigated. Transparent and perfect boules measuring ψ18×60-80mm are grow n by means of Gzochralski method using iridium crucible and inducting heating. Laser rods of the sizeGadolium gallium garnet crystals substituted with Ca,Mg, and Zr and doubly-doped with Nd and Cr are grown, and their laser properties are investigated. Transparent and perfect boules measuring ψ18×60-80mm are grow n by means of Gzochralski method using iridium crucible and inducting heating. Laser rods of the size of ψ5 × 40mm are machined. The output slope efficiency obtained was 0.7. Comparison of spectroseopic properties and lattice constant of the crystal with those of GGG crystals doubly doped with Nd, Cr and substituted with a small amount of So is made and a discussion is given..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 710 (1986)
Spectroscopic properties of Er3+ ions and ErP5O14 crystals
Su Qiang, Wang Qingyuan, Yu Yaqin, and Dong Xiangming
Intensity parameters Ωλ(or τλ) of Er3+ in crystal ErP5O14 were calculated by Judd-Ofelt theory. With these Ωλ valus, the oscillator strength, spontaneous radiative transition rate,seadiative lifetime, branching ratio and integrated emission cross section were calculated. In comparison with integrated emission cross secIntensity parameters Ωλ(or τλ) of Er3+ in crystal ErP5O14 were calculated by Judd-Ofelt theory. With these Ωλ valus, the oscillator strength, spontaneous radiative transition rate,seadiative lifetime, branching ratio and integrated emission cross section were calculated. In comparison with integrated emission cross section of certain laser crystals such as YAlO3:Er3+ and-CaF2:Er3+, the potential application of ErP5O14 as laser material was discussed..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 714 (1986)
Study on genetic effects of Drosophila melanogaster by using laser irradiation
Geng Zhencheng, Zhang Dan, Gu Shaohua, Zhu Dingliang, Jiang Huifang, Zheng Qike, Wang Zhilin, and Pan Hunxi
The genetic effect of three stocks of D. melanogaster, C. S., Base, and bw-st/bw-st were studied with irradiation from He-Ne, nitrogen and argon ion lasers. Experimental results show that when the radiation dosages of He-Ne laser, nitrogen laser and argon ion laser amounted to 32J/cm3, 0.75J/cm2 and 196J/cm2, respectivThe genetic effect of three stocks of D. melanogaster, C. S., Base, and bw-st/bw-st were studied with irradiation from He-Ne, nitrogen and argon ion lasers. Experimental results show that when the radiation dosages of He-Ne laser, nitrogen laser and argon ion laser amounted to 32J/cm3, 0.75J/cm2 and 196J/cm2, respectively, genetic effects of recessive lethal mutation and translocation have not been observedyet..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 720 (1986)
High precision inspection of laser materials
Qiao Jingwen, and Deng Peizhen
Mark Ⅲ system provides both fringe measurement technique and phase measurement technique to perform optical wavefront measurements for wide spectroscopic application. Optical plates, spheres, lens systems and optical materials have been tested with fringe and phase measurement techniques.Mark Ⅲ system provides both fringe measurement technique and phase measurement technique to perform optical wavefront measurements for wide spectroscopic application. Optical plates, spheres, lens systems and optical materials have been tested with fringe and phase measurement techniques..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 725 (1986)
Spectral and laser pro perties of laser dye carbostyil 124
Yan Fujun, Huang Dezhao, Cheng Zhusheng, and Teng Yueli
Laser dye carbostyil 124 was synthesized. The spectral and laser properties of it were given and the tunable wavelength ranging from 400 to 438nm, with λmax at 419nm was found. Com-pare with coumarin 120, the wavelength is blue-shifted and the efficiency is lower.Laser dye carbostyil 124 was synthesized. The spectral and laser properties of it were given and the tunable wavelength ranging from 400 to 438nm, with λmax at 419nm was found. Com-pare with coumarin 120, the wavelength is blue-shifted and the efficiency is lower..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 727 (1986)
UV laser emission from plasma electrodes
Yao Yongbang, Li Chengqi, and Ma Shusen
UV laser emission has been obtained by metal piece discharge generated plasma as preionization source and main discharge cathode.UV laser emission has been obtained by metal piece discharge generated plasma as preionization source and main discharge cathode..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 729 (1986)
Optogalvanie spectros copy of higher excited states in Cs atoms
Wang Wei, Yang Yukun, Jiang Zhangkui, and Luo Xingyie
Spectrum of higher states, excited from 6P2 to S and D states in Cs atoms by optogalvanic spectroscopy are measured and the experimental results are compared with the calculated ones.Spectrum of higher states, excited from 6P2 to S and D states in Cs atoms by optogalvanic spectroscopy are measured and the experimental results are compared with the calculated ones..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 729 (1986)
Influence of He-Ne laser light on human heart function
Zhu Jiayi, Ma Jinghua, Li Yongpei, and CAI Baofen
Variation of some medical parameters of the human heart function before and after He-Ne laser irradiation is reported. It shows that LVEF of the patients with coronary heart disease and non-coronary heart disease has been increased obviously (P 0.05) after some parts are irradiated.Variation of some medical parameters of the human heart function before and after He-Ne laser irradiation is reported. It shows that LVEF of the patients with coronary heart disease and non-coronary heart disease has been increased obviously (P<0.05) after the points are irradiated. Though LVEF has been increased a little bit but not very clearly(P> 0.05) after some parts are irradiated..
Chinese Journal of Lasers
- Publication Date: Jan. 01, 1900
- Vol. 13, Issue 11, 732 (1986)
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