摘要 |
A laser drawing apparatus according to the invention calibrates the accuracy of a first light quantity monitor in detecting the quantities of laser beams, based on results of detection by a second light quantity monitor of the quantities of laser beams emitted from an imaging optical system to a drawing stage, when a characteristic deterioration of or adhesion of foreign matter to optical components of the first light quantity monitor has resulted in variations in the optical characteristic of the first light quantity monitor, and variations in the detection by the first light quantity monitor of the quantities of the laser beams. The quantities of the laser beams emitted to a printed circuit board (image-receiving object) is thereby adjusted to a proper value, to maintain high-quality, high-definition drawings requiring a high degree of light quantity precision.
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