WIDTH MEASUREMENT USING LASER TRIANGULATION
Width may also be measured using two laser triangulation sensors. The subtraction method allows the object to have different widths or to be at different positions between the sensors without influence on the measuring result.
Basically, width measurement works like thickness measurement. As a single spot is difficult to place on an edge and little up and down movement may cause the sensor to lose the edge ANTARIS BAND uses a short line perpendicular to the edge. The edge just needs to be somewhere in the range of the line to be detected.
For this measuring method the strip thickness has to be more than 4 mm.
WIDTH MEASUREMENT USING LASER SCAN MICROMETER
Laser-scan-micrometer consist of emitter and receiver. LAP METIS sensors use a light plane generated by a laser beam, which is deflected by a rotating prism and directed by a lens.
In the receiver, the laser is focused on a diode. For each pass, the laser needs a fixed time interval.
If there is an object in the laser plane, the receiver is shadowed for a certain amount of time. This time is proportional to the dimension of the object.