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:
Feb. 25, 1986
Filed:
Jan. 26, 1984
Siegfried Reininger, Deizisau, DE;
Albert Wiesmeier, Esslingen, DE;
Abstract
An electrically dimmable rear-view mirror for motor vehicles of simple and robust construction, suitable for use as an outside mirror or as an interior mirror possessing a transmission layer which is composed of a PLZT ceramic, on which a linear birefringence can be imposed by means of a controlling electric field. The transmission layer is located between a linear polarizer and a reflective layer, the latter being designed as a dielectric multilayer arrangement. Suitable comb-type electrodes are located on that side of the reflective layer which faces away from the transmission layer and, if appropriate, on that side of the polarizer which faces the transmission layer, the function of these comb-type electrodes being to generate the controlling field. The polarizer defines the direction of polarization, which is inclined at 45.degree. with respect to the field direction and/or the optical axis of the transmission layer. The strength of the electric field controlling the dimming effect is regulated in a manner such that the effective reflectivity of the rear-view mirror is reduced to suit the prevailing situation, this field-strength regulation being accomplished by a photoelectric control system which reacts, on the one hand, to the brightness of the surroundings and, on the other hand, to the intensity of a luminous flux passing through the polarizer and the transmission layer.