Dimming installations require a compatible dimming ballast. This circuit is called a Leading-Edge Dimmer or Forward Phase Dimming. The term brownout comes from the dimming experienced by incandescent lighting when the voltage sags. Power steering, windows, seats, and auto headlight dimming were optional. The Gentex auto dimming rear view mirrors were updated. It is also very apparent with dimming ballasts. He insisted on dimming the house-lights during performances. It provides PWM/ output for direct dimming control and UART interface for integration purposes. Other descriptions of this experience include a monocular blindness, dimming, fogging, or blurring. Only some CFLs are labeled for dimming control. Aircraft engines emit noise pollution, gases and particulate emissions, and contribute to global dimming. Some wall switch modules offer a feature called "local dimming". Increased suction causes a transient dimming of vision in the treated eye. The phenomenon underlying global dimming may also have regional effects.