Patent ID: 6621555
Filing Date: 2003-09-16
Classification: G02B,G03F

Abstract:
A projection exposure apparatus, comprising:a projection optical system for projecting a pattern of a reticle onto a photosensitive substrate, wherein said projection optical system includes at least three lens units, including a lens unit of a positive refractive power and a lens unit of a negative refractive power, and said at least three lens units including an aspherical lens having aspherical surfaces formed on both sides thereof, wherein a relation |LxÃ¸0|>17 is satisfied, where L is a conjugate distance of said projection optical system and Ã¸0 is the total power of the negative lens unit or of negative lens units of said projection optical system, wherein each aspherical surface of said aspherical lens is disposed at a position satisfying a relation |hb/h|>0.35 where h is a height of an axial marginal light ray, and hb is a height of a most abaxial chief ray, and wherein each aspherical surface of said aspherical lens satisfies a relation |&Dgr;ASPH/L|>1.0Ã—10âˆ’6 where &Dgr;ASPH is an aspherical amount of the surface of said aspherical lens.