LARGE APERTURE OPTICAL SYSTEM Russian patent published in 2015 - IPC G02B9/60 G02B11/30 

FIELD: physics.

SUBSTANCE: device comprises positive and negative meniscus lenses arranged along the beam and with their convexity facing the subject, aperture diaphragm, negative component glued of biconcave lens and biconvex lens, biconvex lens and positive meniscus lens with its concavity facing the image. Negative meniscus lens satisfies the following terms: 2.5 mm≤r₄(r₃-d₃)/[n₂r₄-(n₂-1)(r₃-d₃)]≤2.7 mm; 1.723≤n₂≤1.734; 27.9≤υ₂≤29.3, where r₃ and r₄ are negative meniscus lens radii; d₃ is negative meniscus lens depth; n₂ is negative meniscus refractive exponent; υ₂ is negative meniscus lens Abbey number.

EFFECT: improved manufacturability, high image quality.

1 dwg 3 tbl