Fast Discharge Circuit for Longitudinally Excited CO2 Laser

  • Kazuyuki Uno
  • Hiroyuki Hayashi
  • Tetsuya Akitsu
  • Takahisa Jitsuno


In a longitudinally excited CO2 laser with a short laser pulse, similarly to TEA and Q-switched CO2 lasers, a fast discharge is very important. We investigated the use of a fast discharge circuit to obtain a high spike laser pulse in a longitudinally excited CO2 laser. We compared a traditional capacitor-transfer circuit having a buffer capacitance of 700 pF with our direct-drive circuit in which the buffer capacitance is removed. The direct-drive circuit produced a fast discharge and a high spike laser pulse. We also investigated the effect of a resistance connected in parallel with the discharge tube to eliminate low discharge current after the main discharge. A low resistance of 1 kΩ or less acted as a shunt resistance. The shunt resistance was effective in decreasing the energy of the laser pulse tail at high gas pressure.


Longitudinal excitation CO2 laser Fast discharge Laser pulse shape 



This research was partially supported by the Amada Foundation, AF-2009213, 2010–2011, and by the Japan Science and Technology Agency for A-STEP, AS231Z01538F, 2011. We would also like to thank Seidensha Electronics Co., Ltd. of Japan.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Kazuyuki Uno
    • 1
  • Hiroyuki Hayashi
    • 1
  • Tetsuya Akitsu
    • 1
  • Takahisa Jitsuno
    • 2
  1. 1.Interdisciplinary Graduate School of Medicine and EngineeringUniversity of YamanashiKofuJapan
  2. 2.Institute of Laser EngineeringOsaka UniversitySuitaJapan

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