Abstract: The invention relates to a drive unit for the adjustment of the zoom, focus or iris ring of a camera lens. According to the invention, the drive unit comprises a drive shaft arranged parallel to the axis of the camera lens, a pin and groove arrangement for allowing axial displacement of the drive shaft, a pinion connected to the drive shaft and coupled to the external teeth of a lens ring of the camera lens, and two circular flanges connected to the drive shaft and for embracing a sector of the lens ring to pull along the drive shaft and the pinion as the lens ring moves axially. The invention creates a drive unit which allows adjustment of a lens ring even if the lens ring is displaced axially.