Patent ID: 7071625

Claim:
An LED illuminator with capability of stable brightness which has functions of emergent lighting and night lighting, comprising: a battery module for outputting an internal working voltage of the LED illuminator; a charging unit, which is connected to an external alternating current power source, for transforming the external alternating current power source to an external working voltage to charge the battery module; a switching unit, which is connected to the charging unit, for switching the power source with the internal working voltage when the external working voltage discontinues and activating the emergent lighting function; a display unit, which is connected to the switching unit for receiving the internal working voltage thereby lighting; a detecting unit, which is connected to the display unit, for detecting brightness outside the LED illuminator and activating the display unit for night lighting when the brightness discontinues; and a voltage-stabilizing unit, which is connected to the switching unit, for stabilizing the internal working voltage by boosting and bucking the internal working voltage to a predetermined voltage level when the internal working voltage fluctuates and transmitting the stabilized voltage to the display unit.