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:
May. 22, 1990
Filed:
Jan. 19, 1989
Yutaka Nakata, Isehara, JP;
Ichikoh Industries, Ltd., Tokyo, JP;
Abstract
The projector-type head lamp for use on vehicles according to the present invention comprises a reflector formed by a concave mirror having two foci, light source disposed near the first focus of the reflector, and convergent lens disposed opposite to the reflector with the second focus of the reflector located at the intermediate position between the lens and reflector. The convergent lens has an optical axis which is also the optical axis of the reflector and a focus located near the second focus of the reflector. There is provided near the focus of the convergent lens a shade which has a cut-off edge nearly in contact with the optical axis to produce a shaped beam. The convergent lens is composed of a frontal surface defined by an aspherical plane and a back surface defined by a flat plane which is so inclined in relation to the optical axis as to be nearer to the focus of the convergent lens as it goes from the upper portion toward the lower portion. Thereby, the color fringes caused by the chromatic aberration of the convergent lens appear within the main illuminated zone below the light-dark limit so that the existence of the color fringes is not conspicuous.