Comparison between laser stylus and contact stylus measurements on rough surfaces

Abstract

The introduction of submicron sensitive laser stylus profilometers1,2 based on the compact disk (CD) laser pick-up head and operating by an auto focusing technique, has opened up a new area for non-contact surface roughness measurement in the critical micron range. As many machined surfaces, paper surfaces and painted coatings have surface structures in this roughness range the field for applications is very wide. Careful investigations are therefore needed to show how the laser stylus technique compares with the common technique of contact stylus measurements. This paper, which is related to a thorough study on surface roughness of paper and ceramic materials,3 presents some of the special features observed for the laser stylus instrument.