The Bruker Dektak profilometer measures step heights, surface profiles and roughness using a stylus with a 12.5um radius tip. Step heights can range from ~5 nm to 1 mm, with scan lengths up to 55mm. The stylus force is usually set to 10mg, but can be set below 1mg for soft materials. 3D imaging (using 2D scans) can be done, although this is rather slow compared to an optical profilometer.