公开(公告)号：US20250021009A1

公开(公告)日：2025-01-16

申请号：US18714411

申请日：2022-11-22

Applicant: ASML NETHERLANDS B.V. P.O.

Inventor： Ferry ZIJP

IPC: G03F7/00 ,  G03F7/20 ,  H01J61/16 ,  H01J61/30 ,  H01J61/33

Abstract: An optical assembly includes a bulb and a lens for a laser-operated light source. The bulb has a chamber for accommodating an ionizable gas and a plasma formed by energizing the ionizable gas and has a longitudinal axis and a transverse axis perpendicular to the longitudinal axis. In use, the lens is arranged to focus a wavefront of radiation from a laser to a virtual object point located inside the chamber. In use, the bulb is arranged to transmit and refract the wavefront of the radiation to a first real image point in a first cross-section of the longitudinal axis and a second real image point in a second cross-section of the transverse axis. The first real image point and the second real image point are image conjugates of the virtual object point. The virtual object point, the first real image point and the second real image point coincide.