Techniques for non-contacting thickness or caliper measurements of moving webs or sheets employ a sensor device that includes a first sensor head and a second sensor head that are spaced apart to define a path through which the moving web travels. The sensor device projects a laser generated, multiple points pattern onto the upper surface of the moving web. Pattern recognition algorithm analysis of the pattern identifies the orientation, e.g., tilt, of the moving web. The device further measures the film tilt, the distance between the first sensor head and the first web surface, the distance between the second sensor head and the second web surface, and the distance between the two sensor heads to provide a highly accurate on-line thickness measurement of the moving web.

 
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