To provide a replacement electric bulb for an incandescent light bulb appliance having improved lifetime and durability without converting energy to heat.

In a replacement electric bulb assembly 10 used in an incandescent light bulb appliance, a light-emitting diode (LED) 14 is utilized. The LED is connected to a cap 12 stored in a typical incandescent light bulb appliance. The LED is electrically connected to the cap and a center post inside the cap so that an electrical circuit is composed when the LED is mounted to the inside of the incandescent light bulb appliance. A control unit is connected to the LED so that the output of the LED is adjusted. The control unit can also be used so that required conditions for the voltage or current of the electric bulb assembly are adjusted for allowing the control unit to be utilized in DC current or AC current applications. An external shield or lens 52 or an internal shield or lens 50 is added to the electric bulb assembly or LED directly to change radiated light.