CONTROL CIRCUIT FOR DIMMING AN ELECTROCHROMIC MIRROR GLASS OF A REARVIEW MIRROR OF A MOTOR VEHICLE

摘要

A rearview mirror incorporates the use of electrochromic mirror glass capable of dimming via electronic controls. The electrochromic mirror glass dims when glare from vehicle driving aft of the motor vehicle impinge on the rearview mirror. The rearview mirror includes a control circuit with a single sensor. The sensor receives glare from aft and ambient light forward the motor vehicle. A light conductor guides light from the two directions. A sensor receives the light from the two directions and is able to discern between the glare light and the ambient light, by filtering the light received from each direction based on color. One color is received from one location and not from the other. The sensor is sensitive to wavelengths and can identify the magnitude of flux received in each color. This allows the interior rearview mirror to identify situations that are appropriate for dimming the electrochromic mirror glass.