Quality control for rotor blades of a wind turbine

Method for verifying the manufacturing quality for a rotor blade (1) of a wind turbine, in which - the rotor blade (1) from an angle different from the perpendicular to the surface angle of light (5) is irradiated, - that from the rotor blade (1) reflected light (5) by a detection device (6, 16) is received, - the position (11, 12) below the surface (7) of the rotor blade (1) on a fiber mat (3) reflected light (5) to the detection device (6, 16) is determined, - from the position (11, 12) on the position of the fiber mat (3) is closed.