Abstract: A device (1) for providing an amount of power to a gas discharge lamp (2) comprises a control circuit (3) for controlling a supply circuit (4) for supplying the power according to a power versus voltage graph (10). A calculator (30) calculates a boundary voltage value as a function of a measured voltage value of a voltage signal that has been measured after a predefined time-interval from a cold start of the gas discharge lamp (2). A more accurate boundary voltage value results in more stability and in less time required to reach a steady state. The calculator (30) may be arranged for calculating the boundary voltage value as a function of a minimum voltage value of the voltage signal and of a steady state voltage value of the voltage signal. A memory (31) may store voltage values of the voltage signal and a processor (32) may update these voltage values.

Abstract: The present invention relates to a method of operating an electrical discharge device (12) comprising at least one first electrode (14) and at least one second electrode (16) at a distance therefrom, which electrodes are electrically connected to a power supply (18) and, upon ignition of a first gas discharge (22) between the electrodes (14, 16), transmit an electrical current (I), as a result of which a plasma (24) is produced in a working gas (26), which plasma emits radiation (28), in particular extreme ultraviolet and/or soft X-ray radiation, which is passed via a solid angle (30) into a chamber (32) outside the electrodes (14, 16). In order to prevent erosion at the electrodes (14, 16), it is proposed that the formation of a secondary plasma (34) in the chamber (32) is suppressed by a device (42).

Abstract: A device (1) for providing an amount of power to a gas discharge lamp (2) comprises a control circuit (3) for controlling a supply circuit (4) for supplying the power according to a power versus voltage graph (10). A calculator (30) calculates a boundary voltage value as a function of a measured voltage value of a voltage signal that has been measured after a predefined time-interval from a cold start of the gas discharge lamp (2). A more accurate boundary voltage value results in more stability and in less time required to reach a steady state. The calculator (30) may be arranged for calculating the boundary voltage value as a function of a minimum voltage value of the voltage signal and of a steady state voltage value of the voltage signal. A memory (31) may store voltage values of the voltage signal and a processor (32) may update these voltage values.

Abstract: The present invention relates to a method of operating an electrical discharge device (12) comprising at least one first electrode (14) and at least one second electrode (16) at a distance therefrom, which electrodes are electrically connected to a power supply (18) and, upon ignition of a first gas discharge (22) between the electrodes (14, 16), transmit an electrical current (1), as a result of which a plasma (24) is produced in a working gas (26), which plasma emits radiation (28), in particular extreme ultraviolet and/or soft X-ray radiation, which is passed via a solid angle (30) into a chamber (32) outside the electrodes (14, 16). In order to prevent erosion at the electrodes (14, 16), it is proposed that the formation of a secondary plasma (34) in the chamber (32) is suppressed by a device (42).