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:
Jul. 31, 1990
Filed:
Nov. 30, 1989
Kunio Akizuki, Shiraokamachi, JP;
Ichikoh Industries Ltd., Tokyo, JP;
Abstract
The inner reflecting surface of the concave mirror of the projector-type headlamp is composed of a central spherical area and a composite ellipsoidal surface of revolution formed by parts of a plurality of different ellipsoidal surfaces of revolution, smoothly joined to each other for junction with the central spherical area, having a common focus at the center of the spherical area and other foci, respectively, at positions spaced ahead of a predetermined distance from the common focus. The lamp bulb is so disposed so as to have the center thereof located near the common focus, and the convex lens is so disposed as to have the focus thereof located near the common focus. The ellipsoidal surfaces of revoltion are so shaped geometrically as to reflect in directions toward their respective other foci the rays emitted from the lamp bulb and incident upon the ellipsoidal surrfaces of revolution, and the convex lens is so designed as to have the focus thereof located near the common focus of the ellipsoidal surfaces of revolution at which the lamp bulb is located. Thereby, it is possible to decrease the total length of the optical system, design compact the entire structure of the projector-type headlamp and increase the effective solid angle of the rays emitted from the lamp bulb, thereby permitting to utilize the rays from the lamp bulb to full extent for definition of a predetermined luminous intensity distribution pattern.