Systems and methods are disclosed for cosmetic injection. The standby high voltage generating means detects a level of a high voltage in both a standby mode and an active mode to boost the high voltage when the level of the high voltage is lower than a predetermined level. A slider block is coupled to a door handle and to the tongue so that the tongue can be swiveled to a disengaged state by use of the door handle, in order to open the vehicle door. Consequently, blue emission can be obtained from the first light-emitting layer and green and red emission can be obtained from the second light-emitting layer.