Image reader and image reading method

摘要

In an image reading method, an image of an original document is read at a plurality of positions within one period in a manner that the focal position spaced a specific distance apart from the surface of the original document is periodically varied while being moved in the slow scan direction. The plurality of read positions during one period are synchronized every period. In-focus image data is detected from the image data read out during each period. Other image data than the detected in-focus image data during one period is replaced with the in-focus image data. Alternatively, blur of other image data than the detected in-focus image data during one period is corrected on the basis of the in-focus image data. An image reader based on the image reading method is also disclosed.