Roughness effects on laser scattering patterns

This work reports on the use of a CMOS sensor with 1440×1080 pixel resolution, to measure changes on the scattering laser light patterns on aluminum surfaces due to different average roughness. The laser beam strikes perpendicularly to the grinding direction. As expected, the higher the roughness, the larger the area of scattered light on the detector. The detector has three channels: red, green and blue (RGB space). A statistical analysis of the intensity per pixel in each channel was measured, the red channel was chosen because it provided more information. Finally, a transversal cut along the scattering patterns show a relation between surface roughness and the width of the scattering distribution.