| 摘要 |
The invention relates to a sensor assembly for optically detecting the edges of a product, in particular for measuring the width of said product by determining the light propagation that is influenced by the product. According to the invention, a row of locally defined, individually controllable point-type light sources is located on one side of the product and is used in conjunction with at least one fibre-optic unit, which runs parallel to the row of light sources, is optically insulated from the latter and optically couples the respective light that is emitted by the light sources and reflected by the product and at least one photo-detector is connected to the fibre-optic unit. As the location of the respective preferred light sources is known and said point-type light sources are successively or selectively controlled, or controlled in small groups, detection of the edges takes place in the following manner. During control of the n-ten point-type light source, a reflection signal falls on the fibre-optic and is conducted to the photo-detector, the position of the edge of the product web can then be determined as a result of the unique assignment of the respective light source that has just been controlled in relation to the location. The resolution for the product width information is determined by the smallest respective unit of the point-type light sources, the distances between said units, or the relationship of the apertures. |
