Abbe sine condition

Definition: A condition that must be met by any lens to be spherically corrected and free from coma near the lens axis. * It is expressed as: u+/Sin U+ = u/Sin U where u, u+ are the angles of the entering and emerging portions of a paraxial ray from object to image and U, U+ are the corresponding angles of a marginal ray. * First stated by Ernst Abbe.

Previous Term: Abbe number  Next Term: aberration

Type a photography term below to find its definition: