AUTO-ZOOM LENS Russian patent published in 2005 - IPC

FIELD: optics.

SUBSTANCE: first positive component has positive lens, glued from negative meniscus, directed by convex surface to a space of objects, and biconvex lens, and positive meniscus, directed by convex surface to objects space and glued together from biconvex and biconcave lenses. Second component contains biconvex lens of negative bi-glued meniscus, directed by convex surface to objects space and consisting of negative and positive meniscuses. Third component is made in form of negative lens, glued from positive meniscus, directed by convex surface to images space, and biconcave lens. fourth positive component consists of two groups of lenses, apart from each other for distance not less than half of back focal length of auto-zoom lens. second and third components are mounted with possible movement along optical axis.

EFFECT: broader range of focus ranges of lens with maintained high quality of image.

6 dwg