Importance

Loading Importance Indicators...

Abstract

A day/night rearview mirror comprises an optical medium which is electrically driven between transmissive and opaque states. The mirror comprises a housing containing a circuit board assembly over which a mirrored reflecting surface is disposed. The mirrored reflecting surface is in turn overlaid by an optical transmission plate containing the optical medium. The transmission plate, mirror and circuit board are retained on the housing by means of a bezel. Electrical conductivity from the circuit board to the transmission plate is provided by helical coiled spring conductors which are conveniently supported in sleeves integrally formed with a retaining frame for the mirrored reflecting surface of the mirror. The circuit board contains a circuit for controlling the optical transmission plate and suitable controls which are accessible to the user to adjust certain operational characteristics of the mirror assembly. It also includes a pair of photodetectors forming sensors which sense general ambient lighting conditions and incident light from the field of view, respectively. The sensors are coupled in electronic input circuits to a logic gate. The output of the logic gate controls the optical transmission plate. The transmission plate is forced to an opaque condition only when both a nighttime ambient condition is sensed and there are also bright lights form the field of view incident upon the mirrored reflecting surface. The circuits impose certain timing requirements on changes in sensed conditions so that the mirror does not change state in response to momentary departures form generally prevailing conditions.

Loading the Abstract Image...

First Claim