Patent Document ID: 5532824
Application ID: 08430425
Patent Status: 1

Claim One:
1. A method for determining a position of an object having a first pattern thereon, the object moving within a region with respect to a reference coordinate system, the method comprising the steps of: projecting a second pattern upon a surface of the object; sensing an image of the region including an image of the first pattern and an image of the second pattern, said image constituting a fixed defined portion of the region; providing an image signal representing the image of the fixed defined portion of the region; and analyzing the image signal to detect positional changes of the image of the first pattern in the image of the fixed defined portion of the region and to detect positional changes of the image of the second pattern in the image of the fixed defined portion of the region and to ascertain the position of the object based on a position of the image of the first pattern in the image of the fixed defined portion of the region and on a position of the image of the second pattern in the image of the fixed defined portion of the region.