A plurality of series circuits of saturable reactors and transferring capacitors are connected in parallel to a peaking capacitor, the plurality of saturable reactors are magnetically coupled, and saturable reactors for finely adjusting a transfer initiation time are connected in series to the plurality of saturable reactors. Otherwise, a plurality of series circuits of saturable reactors and transferring capacitors are connected in parallel to the peaking capacitor, the plurality of saturable reactors are magnetically coupled, and post-saturation inductances of the plurality of saturable reactors are made different.

A discharge circuit for pulsed laser 10 in which one connecting portion of a preionization capacitor Cpp is connected to a preionization electrode 4 and the other one connecting portion of the preionization capacitor Cpp is connected to a junction between a capacitor C2 and a magnetic switch AL2. In the discharge circuit for pulsed laser 10, a voltage Vcc of the preionization capacitor Cpp, which is charged in synchronization with the charging of the capacitor C2, increases at a time t3 earlier by a predetermined time than a start time t6 of main discharge by the main discharge electrodes 1, 2. When a voltage of the preionization electrode 4 increases to a predetermined preionization start voltage through the preionization capacitor Cpp, a main discharge gap 3 is preionized by a corona discharge caused by the preionization electrode 4 and the main discharge is caused by the main discharge electrodes 1, 2 with the main discharge gap 3 fully preionized.

An ArF excimer laser device and a fluoride laser device for exposure which is structured so that primary current that infuses energy from a magnetic pulse compression circuit to discharge electrodes via a peaking capacitor overlaps secondary current that infuses energy from the capacitor in the final stage of the magnetic pulse compression circuit to the discharge electrodes, the oscillation cycle of the secondary current is set longer than the oscillation cycle of the primary current, and a pulse of laser oscillation operation is effected by the initial half-cycle of the discharge oscillation current waveform that reverses the polarity of the primary current being overlapped by the secondary current and by at least two half-cycles continuing thereafter, as a result of which a high repetition rate, pulse stretch, line-narrowed ArF excimer laser device and fluorine laser device can be implemented at repetition rate exceeding 2 kHz.

A system and method for a power supply system that charges a capacitor, wherein the capacitor charge drives a pulse discharge driven system. The power supply system utilizes a main power supply and a resonant inductor and capacitor configuration to charge the capacitor to a specified, large percentage of a driving voltage that is required by the pulse system. A control module monitors the capacitor charge and disconnects the main power supply when the capacitor charge is within the specified percentage. The main power supply disconnect causes the inductor to discharge and similarly charge the capacitor in a more controlled manner. Once the control module measures the capacitor voltage at the full driving voltage, the control module commands a switch to separate the inductor from the capacitor. The control module similarly activates a small high voltage power supply that monitors the capacitor and replenishes any natural capacitor discharge that may occur in the time between the full capacitor charge and the capacitor discharge by the pulse discharge driven system. Once the pulse discharge driven system discharges the capacitor, the control module returns the power supply system to its initial state, wherein the main power supply and residual energy in the capacitor cooperate to efficiently charge the inductor and capacitor. The charging cycle continues repeatedly as a function of the pulse discharge driven system requirements.

In a preionization discharge circuit 10, when a switch SW14 is turned on, an electric current i10 from a constant current source 13 flows through a loop of a coil L12, en electrode 11A and the switch SW14. When it is assumed that an inductance of the coil L12 is L (H) and the current i10 flowing through the coil L12 is I (A), energy EL of (1/2).multidot.L.multidot.I 2 is accumulated in the coil 12. Meanwhile, in a preionization discharge control section 40, a preionization discharge timing signal (namely, a corona emission timing signal) Ydt is output to the switch SW14 after lapse of a time ty (=Tds-tyd) after a pulse oscillation synchronizing signal TRL is received so that preionization discharge is caused earlier by a preset time tyd than the preionization discharge timing signal Ydt. When the switch SW14 is switched from on to off according to the corona emission timing signal Ydt, the energy EL accumulated in the coil L12 is abruptly supplied to the electrode 11A of the preionization electrode 11. Then, an electric field is produced between the electrode 11A and an electrode plate 11C and, when the electric field of the preionization electrode 11 rises to a predetermined preionization start electric field, a corona discharge is produced in a tube 11B as a dielectric of the preionization electrode 11 to flow an electric current i11, and a main discharge gap 3 is preionized before the main discharge is caused by main discharge electrodes 1 and 2.