Plan apochromatic objective lens
plan apochromatic objective lens
(Science: physics) A modern, high-numerical aperture microscope objective lens designed with high degrees of corrections for various aberrations. It is corrected for spherical aberration in four wavelengths (dark blue, blue, green, and red), for chromatic aberration in more than these four wavelengths, and for flatness of field. A single plan Apo objective may contain as many as 11 lens elements.