Abstract: A projection optical system is a system with good imaging performance based on well-balanced compensation for aberration associated with image height and aberration associated with numerical aperture, while ensuring a large effective image-side numerical aperture in the presence of a liquid in the optical path between the projection optical system and an image plane. The projection optical system forms an image of a first plane on a second plane. An optical path between an optical member located nearest to the second plane out of optical members with a refractive power in the projection optical system, and the second plane is fillable with a predetermined liquid. The projection optical system satisfies the condition of 0.02<NA×WD/FA<0.

Abstract: Provided is a projection optical system for forming an image of a pattern of a first object (R) on a second object (W). The projection optical system is made of an optical material having a refractive index of not more than 1.6 and is substantially telecentric both on the first object side and on the second object side. The projection optical system satisfies the condition of (?×L)/(NA×Y02)<1.5×10?3, where ? is a wavelength of light, L a distance between the first object and the second object, MA a numerical aperture on the second object side, and Y0 a maximum image height on the second object.

Abstract: A projection optical system that projects an image on a first side onto a second plane through a plurality of lenses includes the following elements in order from the first side to the second plane: a first lens group that has a negative refractive power, a second lens group that has a positive refractive power, a third lens group that has a negative refractive power, a fourth lens group that has an aperture stop in the optical path, and a fifth lens group that has a positive refractive power. A clear aperture of a lens surface or an outer diameter of a lens in the projection optical system has a relative maximum in the second lens group, a relative minimum in the third lens group, and a relative maximum in the third-fifth lens groups, and has only one significant minimum between the first side and the second plane.

Abstract: A projection optical system in which an image of a first surface is projected onto a second surface based on a light beam having a predetermined wavelength. The projection optical system having at least one isometric system refractive member made of an isometric system crystal material. The isometric system crystal material transmits a light beam having the predetermined wavelength. The projection optical system also has an amorphous refractive member made of an amorphous material for compensating deterioration of optical performance due to intrinsic birefringence of the isometric system refractive member.

Abstract: Provided is a projection optical system for forming an image of a pattern of a first object (R) on a second object (W). The projection optical system is made of an optical material having a refractive index of not more than 1.6 and is substantially telecentric both on the first object side and on the second object side. The projection optical system satisfies the condition of (&lgr;×L)/(NA×Y02)<1.5×10−3, where &lgr; is a wavelength of light, L a distance between the first object and the second object, MA a numerical aperture on the second object side, and Y0 a maximum image height on the second object.

Abstract: Excellent optical performance is obtained without substantially any impact of birefringence even when a crystal material with intrinsic birefringence such as fluorite is used.

Abstract: A projection optical system that projects an image on a first side onto a second plane through a plurality of lenses includes the following elements in order from the first side to the second plane: a first lens group that has a negative refractive power, a second lens group that has a positive refractive power, a third lens group that has a negative refractive power, a fourth lens group that has an aperture stop in the optical path, and a fifth lens group that has a positive refractive power. A clear aperture of a lens surface or an outer diameter of a lens in the projection optical system has a relative maximum in the second lens group, a relative minimum in the third lens group, and a relative maximum in the third-fifth lens groups, and has only one significant minimum between the first side and the second plane.