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:
Dec. 10, 1991
Filed:
Nov. 08, 1989
David A Richard, San Diemas, CA (US);
Joel Ltd., West Springfield, MA (US);
Abstract
Disclosed is a lens system for a telescopic camera comprised of a primary lens, a secondary lens and a tertiary lens. The primary lens is a positive lens having a convex front surface and an aspheric back surface which define an optical axis. The secondary lens is a negative lens which has a concave front surface and a concave back. The front surface of the secondary lens is positioned at a predetermined fixed distance adjacent to the back surface of the primary lens and centered with respect to the optical axis. The tertiary lens is a field flattening lens having a convex front surface and a convex back surface. The front surface of the tertiary lens is positioned at a predetermined fixed distance adjacent to the back surface of the secondary lens, wherein the primary, secondary and tertiary lenses have surfaces shaped to focus on an object viewed such that a field of view of about 4.2.degree. is produced, and said lens system is capable of capturing approximately 94% of all incident photons within the optical axis.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile