An apparatus and method for detecting a difference in width of a strip of material from a desired width of material. The apparatus may comprise a light source, a light detector, an alarm, a first fiber optic cable coupled with the light source, a second fiber optic cable coupled with the light detector,...http://www.google.es/patents/US7936277?utm_source=gb-gplus-sharePatente US7936277 - Apparatus and method for width detection
