US Patent 9648702 Two-level LED security light with motion sensor

A two-level LED security light is operated with a motion sensor. When an electric power is supplied, the LED security light is turned on for a low level illumination. When the motion sensor detects any intrusion, the LED security light is switched from the low level illumination to a high level illumination for a short duration time to scare away the intruder. After the short duration time, the LED security light returns to the low level illumination for saving energy. The LED security light includes a power supply unit, a motion sensing unit, a loading and power control unit, and a lighting-emitting unit. The lighting-emitting unit includes one or a plurality of LEDs which may be turned-on or turned-off by control signal generated from the loading and power control unit.