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:
Jan. 29, 1985
Filed:
Apr. 05, 1982
Nobuyoshi Kuno, Yokohama, JP;
Kiyokazu Honda, Zushi, JP;
Abstract
A sealed beam type reflective lamp has an envelope comprising a front lens and a reflector on the inner surface of which is formed a metal reflective film, and a tungsten coil filament arranged inside the front lens. The lamp has excellent converging effect and its light beam does not spread even if the filament is brought closer to the front lens. The front lens consists of a central circular lens element and a plurality of concentric ring-shaped prism elements. The inner surfaces of these prism elements define a stepped inner surface of the front lens. An angle formed by an inner surface of the prism lens element and the central axis of the lamp is greater than that of the prism lens element situated outward thereof. The step difference of the inner surfaces of the adjacent prism lens elements is 0.6 mm or less.