Calibration of optical probe instruments for the measurement of surface microtopography

摘要

Abstract: Although noncontacting instruments for the measurement of the 3D microtopography of surfaces are now widely available and are used on a routine basis in many branches of science and engineering, information on many aspects of their use, from measurement through characterization to interpretation, is still limited. One important area in which clear information is required is calibration. This paper sets out to breach some of the gap by proposing routines for the complete calibration of optical probe based instruments for the measurement of surface microtopography. It is suggested that contacting and noncontacting instruments can be calibrated in a very similar manner, but that a few subtle but relevant differences need to be borne in mind and the calibration routine modified accordingly. The calibration of stylus instruments using a calibrated sphere as practiced by some instrument manufacturers (and as is common practice with coordinate measurement machines - CMM) has been advocated with the observation that this technique might be of even greater relevance in optical probe based systems. A new technique based on optical sensors is also proposed for the calibration of the diameter of the optical probe.!19