Patent ID: 7177460
Filing Date: 2007-02-13
Classification: G01B

Abstract:
1. A surveying instrument for measuring starting and end points of an object with a computer, the surveying instrument comprising: a) a base; b) a work bench located on the base; c) two tracks selectively moving the base and the workbench in a horizontal plane; d) a coordinate board connected to and located below the work bench and having a plurality of grids located thereon, each of the plurality of grids being a square and having an equal-size and a recognizable icon located thereon; e) a first optical sensor located above and projecting towards the work bench; and f) a second optical sensor located below the coordinate board and projecting towards the coordinate board, the recognizable icon being a computer code readable by the second optical sensor, the first optical sensor and the second optical sensor are connected to the computer, wherein, when the object is placed on the work bench, the first optical sensor identifying the starting point, the second optical sensor reading a first recognizable icon of a first grid of the plurality of grids and transferring data of the first recognizable icon to the computer to determine a first pixel block center and defining a value of the starting point, and, when the object is moved by the two tracks, the object, the work bench, and the coordinate board move together and the coordinate board move together, the first optical sensor identifying the end point, the second optical sensor reading a second recognizable icon of a second grid of the plurality of grids and transferring data of the second recognizable icon to the computer to determine a second pixel block center and defining a value of the end point.