AUTO FOCUSING DEVICE AND METHOD OF MASKLESS EXPOSURE APPARATUS

摘要

PURPOSE: An apparatus and a method for auto-focusing a maskless exposing device are provided to implement the focus calibration of spot beam using a measuring optical part before an exposing process. CONSTITUTION: The focus of beam generated from a projection optical part is varied, and the beam is radiated to the surface of a reference mark(102). Image information related to the beam radiated to the reference mark is obtained(104). Based on the image information, the focus of the beam is matched to the surface of the reference mark. A reference distance and a distance to the surface of a target are obtained based on a distance measuring sensor(110). Based on the distances, the focus of the beam is matched to the surface of the target.