Method and device for generating laser pulses

A extreme ultraviolet (EUV) radiation generating device comprising:

• a device for generating laser pulses, the device comprising:
• at least one laser source for generating first laser pulses and second laser pulses, wherein the first laser pulses have at least one beam property that is different from that of the second laser pulses;
• an optical amplifier for amplifying the first laser pulses and the second laser pulses, wherein each respective second laser pulse passes through the optical amplifier offset in time in relation to a respective first laser pulse by a time offset;
• an optical beam splitter for separating the first laser pulses from the second laser pulses based on the at least one beam property;
• a retardation unit for the first laser pulses to pass therethrough, wherein a time duration for each respective first laser pulse to pass through a retardation section of the retardation unit corresponds to the time offset in relation to the respective second laser pulse, and wherein the second laser pulses do not pass through the retardation unit;
• and
• a superposition unit for superimposing the first laser pulses with the second laser pulses to form superimposed laser pulses;
• and
• a vacuum chamber, into which a target material is capable of being introduced in a target area and being irradiated by the superimposed laser pulses to generate EUV radiation.