Patent ID: 8089708

Claim:
A lens system comprising the following components in order from an object side: a first negative lens component being a most object-side lens component of the lens system; at least one positive lens component; a second negative lens component having a concave surface on an image side thereof, the concave surface having a smaller radius of curvature than an object-side surface of the second negative lens component; an aperture stop; a third negative lens component having a concave surface on the object side thereof, the concave surface having a smaller absolute value of the, radius of curvature than an image-side surface of the third negative lens component; and at least one positive lens component, including a positive lens component being a most image-side lens component of the lens system, the aperture stop being disposed with no intervening lens component between the aperture stop and the concave surface of the second negative lens component and no intervening lens component between the aperture stop and the concave surface of the third negative lens component; the lens system satisfying the following conditional expressions: 0.75<SF1<1.60, 0.5 <|Rs− 1 /Rs+ 1|<1.3, where SF1=(R1+R2)/(R1−R2), where R1 is a radius of curvature of an object-side lens surface of the first negative lens component, R2 is a radius of curvature of an image-side lens surface of the first negative lens component, and SF1 is a shape factor of the first negative lens component, and where Rs−1 is a radius of curvature of the concave surface of the second negative lens component and Rs+1 is a radius of curvature of the concave surface of the third negative lens component.