摘要 |
An apparatus for forming a pattern has a scanning-time setter, a time-error detector, a scanning-time corrector, a pulse data selector, and a control pulse signal generator. The scanning-time setter sets a "fine-section scanning-time" as a pass-time of the beam for each section of a series of fine sections. The time-error detector successively detects a time-error between the set fine-section scanning-time and an actually detected fine-section scanning-time for each fine section. The scanning-time corrector successively corrects the set fine-section scanning-time for each fine section on the basis of the time-error to successively generate a corrected fine-section scanning-time. The pulse data selector successively selects a set of pulse data, corresponding to the corrected fine-section scanning-time, from a series of sets of pulse data. The control-pulse signal generator successively generates a sequence of control-pulse signals in accordance with a selected set of pulse data.
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