Metal surface roughness measuring systems and methods based on the guided mode

The present invention discloses a system and method for measuring the roughness of a metal surface based on the guided mode, the detection probe comprises a measurement system, a laser and a detector, the detector probe comprising a light conducting layer of gold plated on the device and a light conducting means film, a gold film with a test surface of the metal constituting the double-sided metal-clad waveguide structure, the air gap between the gold film and the metal surface is measured waveguiding layer, the laser light emitted from the laser into the light conducting means, coupled via the gold film into a double-sided metal-clad waveguide structure, the reflected laser light via the gold film, entering the light conducting means, and then enter the detector through the optical system. Metal surface roughness measuring system based on guided mode, the present invention can be utilized guided mode in the waveguide structure to detect the surface roughness of machined metal, ultra-high sensitivity using the guided mode, the theoretical accuracy of up to 1nm, for various precision instruments processing technology has important significance.