Petzval field curvature

Petzval field curvature, also known simply as Petzval curvature, refers to a specific optical characteristic of a lens system, particularly related to how the lens focuses light onto a plane. Named after the Hungarian physicist Joseph Petzval, this concept is essential in understanding and designing photographic and imaging systems. In an ideal optical system, all rays of light originating from a point source should converge to a point on the image plane, producing a flat image.