Abstract: An extreme ultraviolet light generation apparatus includes a target supply unit, a target passage detection device, a delay circuit, a laser device, a target image capturing device, and a processor. Here, the processor controls the vibrating element to provide irregular intervals between droplet targets adjacent to each other; generates integrated image data by integrating plural pieces of image data imaged at different times; specifies a position, in the integrated image data, of the droplet target most emphasized in the integrated image data; and sets a delay time based on a distance from a position of the most emphasized droplet target to a second detection position.

Abstract: An EUV light generation system includes a chamber, a target supply device supplying a target to a plasma generation region in the chamber, a laser device outputting pulse laser light, a beam sensor measuring one of a position and an angle of an optical axis of the pulse laser light as a first optical characteristic, a first reflection control mirror whose angle is controlled, and a processor controlling the laser device. The processor calculates a first corrected angle based on a first attenuation curve defined by the angle of the first reflection control mirror at an end of an immediately preceding irradiation period, the angle of the first reflection control mirror at a cold state, an elapsed time from a start of the pause period, and a first time constant, and to change the angle of the first reflection control mirror to the first corrected angle, during a pause period.

Abstract: An extreme ultraviolet light generation apparatus includes a target supply unit, a target passage detection device, a delay circuit, a laser device, a target image capturing device, and a processor. Here, the processor controls the vibrating element so that an interval between the adjacent droplet targets becomes irregular, specifies the droplet targets with which standard deviation of a distance from the second detection position to each droplet target is equal to or less than a first threshold, and sets the delay time based on a distance from each of the specified droplet targets to the second detection position so that the specified droplet targets are to be located at the second detection position.

Abstract: An extreme ultraviolet light generation system configured to generate extreme ultraviolet light by irradiating a target substance with laser light includes a nozzle configured to output the target substance, a vibration element that is driven by an input of an electric signal of a rectangular wave and applies vibration to the target substance to be output from the nozzle to generate droplets of the target substance, a first sensor configured to detect energy of the generated extreme ultraviolet light, a second sensor configured to detect energy of the laser light to be radiated to the target substance, and a processor configured to control a duty value of the electric signal for vibrating the vibration element so as to reduce a variation of an energy conversion efficiency calculated based on an output of the first sensor and an output of the second sensor.