Abstract
A profile measurement system using an optical stylus was proposed, which is robust to speckle included in the reflected light from the object surface. This measurement system consists of a displacement-measurement optical system using focus-error detection and a system that only measures speckle noise. Measurements were taken of engineering surfaces for which speckle are easily attained, and it was found that the proposed measurement system could remove the effects of speckle noise and obtain a surface profile close to that obtained by a mechanical stylus instrument.
