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Volume 20, Issue 1
Displaying 1-8 of 8 articles from this issue
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Koichi SHIMODA1992 Volume 20 Issue 1 Pages 1
Published: January 29, 1992
Released on J-STAGE: March 17, 2010
JOURNAL FREE ACCESSDownload PDF (125K) -
Shin'ichi IMAI, Kouichi YAMAGATA1992 Volume 20 Issue 1 Pages 2-10
Published: January 29, 1992
Released on J-STAGE: March 17, 2010
JOURNAL FREE ACCESSHigh brightness pulsed YAG lasers are developed for high precision laser machining and high depth processing. Industrial high brightness YAG lasers have fine focusability with high average powers. In this paper. Advantages of these lasers to cutting and drilling applications are presented.View full abstractDownload PDF (1503K) -
Kou KUROSAWA, Wataru SASAKI, Yasuo TAKIGAWA1992 Volume 20 Issue 1 Pages 11-19
Published: January 29, 1992
Released on J-STAGE: March 17, 2010
JOURNAL FREE ACCESSElectron beam-pumped rare gas excimer lasers are capable of producing intense coherent light in the vacuum-ultraviolet region. Their photons were found to modify the surface of SiO2. The modified surfaces were measured by means of a surface profiler, reflectance and transmission spectra, atomic force microscopy, and X-ray photoelectron spectroscopy. The surfaces were modified when they were used as a cavity reflector for argon and krypton excimer lasers. Silicon was found to be enriched in the surface layers exposed to 9.8 eV photons from an argon excimer laser, but not by krypton excimer laser photons of 8.5 eV. The argon excimer laser photons, surmount-ing the fundamental band gap of SiO2, 9 eV, are assumed to create high-density excitons that induce Si-O bond breaking, resulting in silicon enrichment and oxygen desorption.View full abstractDownload PDF (1200K) -
Kyoji MATSUSHIMA, Noburu SOKABE, Akira MURAI, Tomio ARIYASU1992 Volume 20 Issue 1 Pages 20-30
Published: January 29, 1992
Released on J-STAGE: August 04, 2010
JOURNAL FREE ACCESSDirection characteristics of emission have been observed on an optically pumped far-infrared (FIR) ring laser. The FIR output from a CH3OH laser is emitted in only a direction depending on the tuning of the FIR cavity. This phenomenon is analyzed theoretically by a 3-level laser model supported by a well-known 2-mode laser theory. The model explains the directionality of the FIR output for significant pump detunings and for small pump powers. The model also predicts that bidirectional emission occurs for large pump powers or for small detunings of the pump transition.View full abstractDownload PDF (1174K) -
Hendrik KURNIAWAN, Takao KOBAYASHI, Kiichiro KAGAWA1992 Volume 20 Issue 1 Pages 31-37
Published: January 29, 1992
Released on J-STAGE: March 17, 2010
JOURNAL FREE ACCESSA new method is presented for detecting fluorine atoms with a shock wave plasma induced by bombardment of a TEA CO2 laser beam. Comparison is made between a fluorine neutral emission line (FI 685.6-nm) and a fluorine ionic emission line (FII 385.0-nm) on the pressure dependence and the spatial distribution. The detection limits of FI 685.6-nm line and FII 385.0-nm line are 100 ppm and 900 ppm, respectively. The background equivalent concentration (BEC ) are 0.015% for FI 685.6-nm and 0.02% for FII 385.0-nm. The present method is of great advantage to the direct measurement of solid samples and to reduce sample preparation procedures.View full abstractDownload PDF (656K) -
-Characteristics of Repetitive Operation-Yukio SATO, Mitsuo INOUE, Kenyu HARUTA, Haruhiko NAGAI1992 Volume 20 Issue 1 Pages 38-47
Published: January 29, 1992
Released on J-STAGE: March 17, 2010
JOURNAL FREE ACCESSHigh repetitive operation is demonstrated of a high power XeCl laser with a surface corona dis-charge electrode for preionization and a spiker-sustainer circuit. A novel operating mode (reverse voltage mode) for the spiker-sustainer circuit is proposed, and it is confirmed that the reverse voltage mode is superior to the usual operating mode (the magnetic diode mode) in high repetitive operations, provided that the timing of the preionization is properly set before the application of the spiker voltage to establish a stable discharge with high repetition rate. Repetitive operation over 500 Hz is achieved with a pulse duration of 340 ns. Maximum output power of 505 W is attained with an efficiency of 2.1% at a repetition frequency of 540 Hz.View full abstractDownload PDF (1162K) -
Kouki SHIMIZU, Yunsheng HUO, Takashi YAGI1992 Volume 20 Issue 1 Pages 48-53
Published: January 29, 1992
Released on J-STAGE: March 17, 2010
JOURNAL FREE ACCESSThe 11th anti-Stokes Raman beam (116nm) has been obtained by the Raman scattering of KrF laser radiation in hydrogen at room temperature. Generation of the second- and third-Stokes order with photon-conversion efficiencies of 68% and 47%, respectively, has been obtained from a single-pass hydrogen Raman oscillator. We investigated the effects of optical breakdown by the laser beam on Raman scattering and found that the pumping efficiencies to anti-Stokes orders are reduced by the disturbance in the wave-front of the pump beam caused by the optical breakdown.View full abstractDownload PDF (537K) -
1992 Volume 20 Issue 1 Pages i
Published: January 29, 1992
Released on J-STAGE: March 17, 2010
JOURNAL FREE ACCESSDownload PDF (81K)
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