Apparatus for forming pattern

An apparatus for generating a sequence of control pulse signals comprising:

• a scanning-time setter that sets a fine-section scanning-time as a pass-time of a beam for each section of a series of fine sections, the series of fine sections being defined by dividing a scanning-line into constant-intervals;
• a time-error detector that successively detects a time-error between the set fine-section scanning-time and an actually detected fine-section scanning-time in each fine section;
• a scanning-time corrector that successively corrects the set fine-section scanning-times for each fine section on the basis of the time-error to successively generate a corrected fine-section scanning-time;
• a pulse data selector that successively selects a set of pulse data, corresponding to the corrected fine-section scanning-time, from a series of sets of pulse data, each of said series of sets of pulse data having a different data-array in accordance with the corrected fine-section scanning-time;
• and
• a control pulse signal generator that successively generates a sequence of control pulse signals in accordance with the selected set of pulse data, the sequence of control pulse signals controlling the output-timing of a sequence of writing pulse signals for controlling an optical modulator.

A Method for generating a sequence of control pulse signals comprising:

• setting a fine-section scanning-time as a pass-time of a beam in each section of a series of fine sections, the series of fine sections being defined by dividing a scanning-line into constant-intervals;
• successively detecting a time-error between the set fine-section scanning-time and an actually detected fine-section scanning-time for each fine section;
• successively correcting 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;
• successively selecting a set of pulse data, corresponding to the corrected fine-section scanning-time, from a series of sets of pulse data, each of said series of sets of pulse data having a different data-array in accordance with the corrected fine-section scanning-time;
• and
• successively generating a sequence of control pulse signals in accordance with the selected set of pulse data, the sequence of control pulse signals controlling the output-timing of a sequence of writing pulse signals for controlling an optical modulator.