Auto Dimming Mirror: Operation

Day/night mirror(s) use a thin layer of electrochromatic material between 2 plates of conductive glass. Two photocell sensors signal levels of light to a logic circuit. A forward-facing photocell sensor measures ambient light levels. A rear-facing photocell sensor measures glare from approaching vehicle headlights. When logic circuit senses more light from the headlight sensor than the ambient light sensor, the electrochromatic drive circuit applies voltage to mirror(s). Approximately 1.15 volts is applied to mirror(s) when a large amount of glare is present, causing mirror(s) to darken. Voltage will be reduced to 0.01 volt when both photocells indicate the same light level.

When gearshift lever is shifted into Reverse, battery voltage is applied to mirror reset terminal. Mirror will gradually change to a clear state for better vision when backing up.