A measurement system for monitoring an LED chip surface roughening process is described. A reflective illuminator can run reflectance measurements. A vertical positioning means can adjust a distance between an objective lens and an industrial sample. A horizontal positioning means can move objects in XY plane, and is specifically configured to hold the industrial sample and a reference sample. An optical sensor can acquire images of the industrial sample. A spectrometer can acquire reflectance spectrums of the industrial sample and the reference sample. A processor can control these components. The processor can perform deskew, and calculate an average reflectance and an oscillation amplitude from the reflectance spectrums of the industrial sample.