Satoshi Takemori

Development of a pulsed power supply for a large‐bore copper vapor laser

A pulsed power supply has been developed for exciting a copper vapor laser with a bore diameter of 80 mm and a discharge length of 2890 mm. The pulsed power supply has two thyratrons, an LC‐inversion circuit and a two‐staged magnetic pulse compression circuit. An efficiency of 82% has been obtained which is defined as the ratio of energy stored in the storage capacitor to the output energy of the magnetic pulse compression circuit, with a voltage greater than 40 kV, averaged output power of 24 kW, and voltage rise time of 70 ns. The pulsed power supply was successfully operated for more than 2000 h and an optical output power of 272 W was obtained.

20-kW fast-axial-flow CO 2 laser with high-frequency turboblowers

A 20-kW fast-axial-flow CO2 laser has been realized by using high-frequency turboblowers developed especially for laser operation. Each of the two high-frequency turboblowers utilized in the equipment has a revolution of 8,800 rpm, a gas flow rate of 8.4 m3/s, and an adiabatic head of 4,000 kgf·m/kg. The equipment has six discharge-tubes connected optically in series, and each is 134 mm in diameter, and 1,000 mm in length. Stable glow discharge is established in the large-volume region without any preionization. The laser output power of 20 kW is extracted from an unstable resonator. The output beam through a zinc-selenide window has a diameter of 90 mn.