PURPOSE: To enable image sensing of the whole band at a high speed, by a method wherein, when the image sensing start position of each band is not in the region which can be sensed by a charged particle beam, the image sensing start times of bands subsequent to the above band are delayed.
CONSTITUTION: In a step S1, a CPU reads data like the number of subfields of each band. In a step 2, time necessary for the image sensing of each band is calculated on the basis of the read data. In a step S3, the image sensing end position and the image sensing end time of each band are obtained. In a step 4, the initial value of stage moving speed is obtained. In a step 5, whether the image sensing start position of an i-th band which is now noticed is in the region where image sensing is possible is discriminated. When the image sensing start position exceeds the region where image sensing is possible, sequence is branched to a step 6. In the step 6, the image sensing start time is so changed that the image sensing start of the band is delayed until the image sensing start position of said band reaches the region where image sensing is possible. In a step S7, the above delay is added to the image sensing end time, and modification is completed.
TAKAHASHI YASUSHI
SAKAMOTO JUICHI
DAIKYO YOSHIHISA
