The characterization of roughness of engineering surfaces over an area is an important task for different applications as well as for manufacturing processes. The surface roughness is in particular an important factor in determining the performance of a workpiece. We demonstrate that the fringe projection technique allows very fast three-dimensional surface inspections. The inspection time for an entire measurement is reduced to less than 5 s with standard hardware. Based on a zoom stereo microscope setup, we demonstrate a modular measuring instrument. The magnification-dependent vertical resolution can be as high as 0.1 μm. The special properties for roughness measurements are demonstrated, especially the comparability with a tactile sensor and with other optical sensors, which is discussed in connection with amplitude parameters.
© 1999 Optical Society of America
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
(120.4120) Instrumentation, measurement, and metrology : Moire' techniques
(120.6660) Instrumentation, measurement, and metrology : Surface measurements, roughness
(180.6900) Microscopy : Three-dimensional microscopy
(240.5770) Optics at surfaces : Roughness
Robert Windecker, Stefan Franz, and Hans J. Tiziani, "Optical Roughness Measurements with Fringe Projection," Appl. Opt. 38, 2837-2842 (1999)