A new technique for passively detecting surface position and shape of glass

Abstract

This paper proposes a new technique for passively detecting surface positions and shapes of glass plates. Though there are lots of approaches such as the stereopsis in computer vision, those methods are hardly effective for detecting transparent objects such as glass plates. Recently we have proposed the technique for detecting mirror surfaces, in which the rays of entering and reflecting at the surface are found and reflecting positions are detected geometrically with the triangulation principal. However, it could not be applied to detection of transparent objects such as glass plates, because of reflection rays from rear surfaces. In the proposed method, a new type of the pattern displayed on the pattern plate is used for discriminating rays from front and rear surfaces of glass plates. From the experiment, it is made clear that the proposed technique is highly effective for detecting front surfaces of glass plates.