The roughness tester is also called surface roughness measuring machine, surface finish tester, surface roughness tester, roughness measuring instrument, roughness machine, roughness instrument and many other names. The surface quality characteristics is one of the most important characteristics of the roughness tester application industry , which plays an important role in the measurement of metrology field surface quality checking. Previously, people were using standard sample parts or roughness reference blocks, by the naked eye observation or touch by the hand, to make a qualitative comprehensive assessment of the surface roughness.

Nowadays, the stylus tracing method is also known as the stylus method. When the stylus is directly on the measured surface of the workpiece, it will move up and down in the direction perpendicular to the measured surface due to the peaks and valleys of the measured surface profile, and this movement will be amplified by an electronic device, which will then output the data or graph of the roughness through a meter or other output device.

The surface roughness measuring instrument is characterised by high measuring accuracy, wide measuring range, easy operation, portability and stable working. The roughness tester can be widely applied to the production site and can measure the surface roughness of a variety of machined parts.