Определение spherical aberration в Английский Язык Английский Язык словарь
A type of lens aberration which causes blurriness, particularly away from the centre of the lens
The blurring of an image that occurs when light from the margin of a lens or mirror with a spherical surface comes to a shorter focus than light from the central portion. The changing focal length is caused by deviations in the lens or mirror surface from a true sphere