Controlled buy waving your hand through the air above the light.
Mathmos Airswitch lights
Airswitch lights use Mathmos Airswitch technology to enable you to turn on and off and/or brighten and dim the light without needing to fumble around for a switch. The lights use a sensor to determine where you hand is in relation to it and adjusts the light accordingly. For Airswitch tc, 1 and O move your hand vertically towards the light and it will dim, away and it will brighten, horizontally across the sensor beams and it will turn on/ off. Airswitch Az baby, designed by Azumi, simply turns on/off when you wave you hand over the light.