Lens system for eyepiece of optical instrument - has positive lens group and correction lens with aspherical surface on incident side of lens group

摘要

The eyepiece of an optical instrument such as binoculars or a telescope or a microscope consists of a positive lens group (Le) and a correction lens (Lc). The correction lens (Lc) is mounted on the light incident side of the positive lens group and its surface has an aspherical form. The aspherical surface is defined by a mathematical formula and the thickness of the lens (Lc) is a minimum at the centre and increases in the radially outward direction to a maximum at the outer edge of the lens. USE/ADVANTAGE - The lens system forms the eyepiece of optical instruments and reduces distortion of the image.