| 摘要 |
PROBLEM TO BE SOLVED: To reduce variation in gradation of an image, read using a gray reference member, without making a read operation time long.SOLUTION: An image reader comprises a reference member having gray reference density, a read part, an output part which outputs a read-time line signal and a correction-time line signal having a period longer than the period of the read-time line signal, a conversion part, a correction part, and a control part. The control part performs correction data acquisition processing to acquire correction data by reading the reference member, line by line, based upon the correction-time line signal when the correction-time line signal is output from the output part, and read processing to acquire a gradation value by making shading corrections on the digital data, acquired by reading a document, line by line, based upon the read-time line signal, based upon the correction data when the read-time line signal is output from the output part.SELECTED DRAWING: Figure 6 |
