Abstract: An apparatus for removing a portion of a coating system present in a multi-glazed window including: a decoating component to focus a laser source at a focus distance; two motors to move the decoating component along the X and Y axis; one optical system to detect on which interface the coating system is localized, and to estimate a distance between the decoating component and the detected interface; a third motor to control the position of the decoating component along a Z axis; and a displacement control unit of the third motor to displace the decoating component of a displacement distance equal to the difference between the estimated distance and said the distance in order to focus the decoating component on the detected interface.