The Study of Light Effect on Surface Roughness of Metallic Surface by Using Vision System Technique

This paper describes the image processing method which is one of the non-contact method is applied to measure the mean gray value (Ga) used to predict and calculate the value of surface roughness (Ra) on the specimen. All the specimens image are captured in different light source environment exposure which is Red LED light, white fluorescent and yellow bulb by using Omron CCD camera. The captured image of each specimen are processed by using MATLAB software as to calculate Ga value on the defect area of the captured image. By using formulation, the Ga value is then transform into surface roughness value and compared with manually measured surface roughness (Ra) data. It is found that there is significant effect on surface roughness measurement from different light source, which effect the accuracy of the surface roughness reading. The outcome of the study clearly indicates the effectiveness of white fluorescent light to be used as light source for surface roughness measurement for metallic surface.