Patent ID: 7206076

Claim:
A system for determining and controlling a thickness of a moving web of material using automatic feedback control, the system comprising: a web manufacturing system that controls thicknesses of portions of a web of material during manufacturing of the web of material; a transport system that moves the web of material in a first direction along a transport path, wherein the transport system has associated therewith a plurality of measurement regions, wherein the plurality of measurement regions include a first measurement region and a second measurement region; at least one light source that provides light toward a plurality of segments of the moving web of material within at least the first measurement region and the second measurement region; an interferometer device comprising at least two optical sensors communicably connected to a sampling optical switch, wherein the at least two optical sensors detect a portion of the light reflected from the segments of the moving web of material within the first measurement region and the second measurement region, wherein the optical switch receives the portions of light detected by the at least two optical sensors, and wherein the interferometer device further comprises a light-to-electric converter that generates electrical signals representative of the light received by the optical switch; a computing device that receives the converted electrical signals, wherein the computing device uses algorithms to translate the received converted electrical signals into data corresponding to thickness measurements; wherein the computing device generates a control signal in response to the data corresponding to thickness measurements to provide feedback to the web manufacturing system so as to control the thicknesses of the segments of the moving web of material within the first measurement region and the second measurement region during manufacturing of the web of material.