| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem in which an image reading unit configured to read a front and back of a document by rotation may deviate from an original reading position due to aged deterioration or physical impact from outside and become incapable of accurately reading an image.SOLUTION: An image reading unit having a sensor is rotated in units of predetermined angles to read a white reference member, luminance information pieces on the white reference member are acquired at the respective predetermined angles of rotation, an angle at which a luminance information piece is greater than other luminance information pieces is determined from among the plurality of acquired luminance information pieces at the respective predetermined angles, and the image reading unit is rotated based on the determined angle to correct a reference position of the image reading unit. |
