Patent ID: 8014585

Claim:
An image plotting data obtaining method for obtaining image plotting data used when plotting an image on a substrate by moving an image plot point forming area, which forms an image plot point based on the image plotting data, relative to the substrate and sequentially forming the image plot points on the substrate according to the movement, the method comprising the steps of: associating information of a plurality of predetermined hypothetical image plotting trajectories of the image plot point forming area on the substrate, the trajectories having different start point positions from each other in the direction orthogonal to the relative moving direction, with original image data representing the image, and obtaining information of a plurality of hypothetical image plot point data trajectories in the original image data, each corresponding to each of the plurality of hypothetical image plotting trajectories; obtaining hypothetical image plotting data, each corresponding to each of the hypothetical image plot point data trajectories, from the original image data based on the information of plurality of hypothetical image plot point data trajectories; storing the obtained plurality of hypothetical image plotting data in advance, and setting a correspondence relationship between the hypothetical image plot point data trajectories and the hypothetical image plotting data in advance; obtaining information of image plotting trajectory of the image plot point forming area on the substrate when the image is plotted; associating the obtained image plotting trajectory with the original image data, and obtaining information of image plot point data trajectory of the image plot point forming area in the original image data corresponding to the image plotting trajectory; selecting a plurality of hypothetical image plot point data trajectories corresponding to the obtained image plot point data trajectory from the plurality of hypothetical image plot point data trajectories, and obtaining information indicating the area corresponding to the image plot point data trajectory in each hypothetical image plot point data trajectory indicated by the selected hypothetical image plot point data trajectories; identifying hypothetical image plotting data corresponding to the selected plurality of hypothetical image plot point data trajectories from the plurality of hypothetical image plotting data stored in advance based on the correspondence relationship; obtaining partial hypothetical image plotting data from each of the identified hypothetical image plotting data based on the information indicating the area corresponding to the image plot point data trajectory; and obtaining image plotting data corresponding to the image plot point data trajectory based on each of the obtained partial hypothetical image plotting data.