Study on a novel laser measurement system for float glass thickness

Float glass is a highly standardized high-tech material found in numerous applications, thickness is one of the most important parameters of float glass production. A new non-touch on-line float glass thickness measurement system based on the principle of twice laser refraction and reflection is present. The principle which is superior to traditional laser triangulation method can overcome shake disturbance of mechanical transmission system. By analyzing the glass processing technique and the high temperature environment, a novel sensor probe located in tin bath is designed. Also, the glass cools more than 600°C are mathematically corrected. Linear CCD is employed to scan the glass plates repetitiously to obtain thickness measuring image. An improved barycentre method is put forward to extract the centre line of thickness stripe image. The method can remove the background noise and extract the center points with a sub-pixel precision. By discussed in theory and experiment the measuring range is 2 to 14mm, the resolution is 1μm and the accuracy can within ±0.005mm.