Patent · US Expired

Wide-field and wide-aperture optical system, notably designed for a night channel for periscopes, and periscope fitted out with such an optical system

US5239411A · kind A · utility

5Cited by
9References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 13, 1991
Grant dateAug 24, 1993
Priority date
Expiry dateAug 13, 2011

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF41H5/266
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

The field of the disclosure is that of enlarging optical lenses and, more precisely, binocular optical systems designed to be inserted into the night-time channel of an observation system, between a light intensifier tube and an observer's eyes. The disclosure can be applied especially to observation instruments for armored vehicles and, notably, periscopes for tanks. The disclosed optical system for a binocular device is of the type constituted by two groups, a forward group and a rear group, the rear group being constituted by a bonded doublet with plane rear face comprising a convergent convex lens bonded to a divergent lens, the lenses of the bonded doublet having different and complementary dispersions to compensate for the chromatism, and the focal length of the doublet ranging from 0.85F to 1.05F, where F is the focal length of the binocular device.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.