The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 31, 1978
Filed:
May. 16, 1977
Ernst Leitz Wetzlar GmbH, Wetzlar, DE;
Abstract
A four component six lens element Gauss type objective having an aperture ratio of at least 1:2.4 and a field angle of greater than 40.degree. , comprising in the direction of light travel: a first single component positive meniscus concave toward the diaphragm; a second and third cemented doublet meniscus component concave toward the diaphragm, each of the doublet components having planar bond surfaces and a low positive or negative power of refraction; a diaphragm located between said second and third component; and a fourth single component having positive power of refraction with the weaker surface facing the diaphragm; wherein at least two pairs of spherical lens surfaces which are arranged symmetrically with respect to the diaphragm have identical radii of curvature; wherein the ratio of the dispersion values of the first and sixth lens, of the second and fifth lens, and of the third and fourth lens, respectively, in the direction of light travel, are essentially as follows: