Masashi Ishimine

TEA-CO2 laser oscillation by inductive energy storage pulsed power generator

A pulsed-power technology has been used for production of high power and fast pulses. It is possible that a pulsed-power generator with a storage inductor and an opening switch can be extremely compact and light in comparison with a conventional system. We have carried out the experiments on TEA-CO2 laser oscillation using the inductive energy storage pulsed-power generator. The output energy of the laser and the peak power were 0.3 J and 0.53 MW, respectively.

A TEA-CO2 laser oscillation by an inductive energy storage pulsed-power generator using a wire-fuse opening switch

We have carried out experiments on TEA-CO2 laser oscillation using the inductive energy storage pulsed-power generator, which has a copper wire fuse as an opening switch. Maximum laser output energy of about 1 J/pulse was obtained in the case of a fuse length of 5 cm and energy storage inductance of 8 μH. The laser output energy depends on the energy storage inductance and the parameters of the fuse. In this paper, the dependencies of laser output energy on inductance and fuse length, and a comparison between the inductive and capacitive system were described. Furthermore the laser efficiency was discussed by calculating the electron energy distribution of laser main discharge region.

Fundamental Studies of Ozone Generation and Its Characteristics Using New Type of Ozonizer

Fundamental studies of a new type of ozonizer, which has no dielectrics between main metal electrodes and has a circuit called charge transfer, have been carried out. The rate constant k1 for the reaction of O+O2+O2→O3+O2 has been measured through absorption measurements using the 253 nm line of a mercury lamp in He/O2 mixtures at atmospheric pressure.

Characteristics of a plasma production and a laser‐induced discharge by a CO2 laser on DC electric field

The experiments of a laser‐induced discharge were carried out with a CO2 laser radiation in the atmospheric ambient gases under a DC electric field applied. In these experiments, both of the laser‐induced discharge and the plasma production by the CO2 laser were suppressed with an increasing DC electric field strength. Although the laser‐produced plasma was generated between the electrodes without DC electric field, both the probability of induced‐discharge and plasma production decreased with the applied voltage across the electrodes. In this paper, the mechanisms of the phenomena for the suppression of the plasma production under applying the electric field between electrodes were discussed. It was found that the attachment processes of electrons most likely played an important role in this phenomena.

Plasma Opening Switch Using Plasmas Produced by a Pulsed CO2 Laser

Plasma opening switches were studied using laser-produced plasmas. In this paper, a CO2 laser (5 J/pulse, 5.5 MW peak power and 10.6 µm wavelength) was used as the plasma source of a plasma opening switch (POS). The plasma parameters were measured using a Faraday cup, a Langmuir probe and a monochromator. It was found that ions with fast flow velocity are required to obtain a short opening time, and thermalized plasma with low velocity lengthens the opening time. However, POS operation was improved by switch modification despite the existence of thermalized plasmas.

Plasma opening switch using plasmas produced by a pulsed CO/sub 2/ laser

Plasma opening switches have been studied by using laser-produced plasmas. In this paper, a CO/sub 2/ laser (5 J/pulse, 5.5 MW peak power and 10.6 /spl mu/m wavelength) was used as a plasma source of the plasma opening switch (POS). The plasma parameters were measured by Faraday cup, Langmuir probe and a monochromator. It was found that ions with a fast flow velocity are required to obtain the fast opening time, and thermalized plasmas with a slow velocity decrease the opening time. However, the POS operation was improved by the switch modifications despite the existence of thermalized plasmas.