EYE-PIECE Russian patent published in 2007 - IPC G02B25/00 

FIELD: optics.

SUBSTANCE: eye-piece has two components disposed one after the other along path of beam from object. First component is single biconvex lens. Second component is double-lens one, glued of biconvex lens and negative menisci, turned with its convexity to image. Exit pupil is disposed behind negative meniscus. Relations are met among refractivity and coefficient of dispersion of material of first, second and third lenses for line e, which relations are given in formula of invention. Radius of first optical surface if second component relates to radius of last optical surface of second component as 0,8-0,96 in absolute value.

EFFECT: increased front focal section and angle of field of view; simplified optical circuit; improved manufacturability.