| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image reading device that accurately detects the size of documents. <P>SOLUTION: When a document presser plate is in a half-open state (step S11: YES), a document reading part 4 reads an image for one line (step S12), and a document size detection part calculates brightness of the document from the image (step S13). If the brightness of the document is higher than a set value, that is, the brightness of the document is close to white (step S14: NO), the document size detection part detects the size of the document using the image read in step S12 (step S17). If the brightness of the document is equal to or lower than the set value, that is, the brightness of the document is gray or black (step S14: YES), when the document presser plate 3 is in a closed state (step S15: YES), the document reading part 4 reads the image for one line again (step S16), and the document size detection part determines the size of the document using the image (step S17). <P>COPYRIGHT: (C)2012,JPO&INPIT |
