SYSTEM AND METHOD FOR FOCUSING A CHARGE COUPLED DEVICE LENS ON A SELECTED SURFACE OF AN OBJECT

摘要

A positioning system and method for focusing a charge coupled device (CCD) lens on a selected surface of an object to be measured is provided. The positioning system and method moves the CCD lens downwards to approximate an estimate Z-axis coordinate of the CCD lens, and moves the CCD lens upwards to find an accurate Z-axis coordinate of the CCD lens according to the selected surface of the object. The system and method further moves the CCD lens to a position corresponding to the accurate Z-axis coordinate to focus the CCD lens on the selected surface.