HIGH-APERTURE LENS Russian patent published in 2016 - IPC G02B9/62 

FIELD: physics.

SUBSTANCE: high-aperture lens consists of six components arranged on a beam path. The first component is a separate plane-concave lens facing the image plane. The second component is a meniscus facing the object with its concave side and glued from a biconcave and a biconvex lens. The third and fourth components are biconvex lenses with equal structural parameters, facing each other by optical surfaces whose curvature radii are smaller in magnitude. The fifth component is glued from a biconvex lens and a biconcave lens, facing the image plane. The sixth component is a separate plane-concave lens facing the object plane.

EFFECT: high aperture ratio and a wider angular field in the object space with high image quality.

1 dwg, 2 tbl