IMAGE READING METHOD AND APPARATUS, AND IMAGE FORMING APPARATUS EMPLOYING THE SAME

PROBLEM TO BE SOLVED: To provide an image reading method and apparatus capable of allowing a overlapping feed detection means to detect overlapped sheets in a stage of feeding sheets from a stacker to a platen and reading a series of the sheets with no missing without the need for maintenance by a user when the sheets are overlappingly fed. SOLUTION: The image reading apparatus is provided with: the stacker on which sheets are located; a separation means for separately and sequentially feeding the sheets on the stacker; a sheet carrying guide for guiding the sheets from the separation means to a read platen; and an overlapping feed detection means for detecting whether or not two overlapped sheets or more exist in the sheet carrying guide. The overlapping feed detection means discriminates whether a single sheet or a plurality of sheets are carried by arranging a light emitting element and a light receiving element such as photo diodes and ultrasonic sensors opposite to each other while sandwiching the sheets inbetween and comparing a detected value of the light receiving element with a prescribed value and includes: a page order discrimination means for discriminating the feed order of the sheets fed from the stacker; and an overlapping feed identification means for identifying the page order of the overlappingly fed sheets on the basis of overlapping feed detection information from the overlapping feed detection means and page order information from the page order discrimination means. COPYRIGHT: (C)2005,JPO&NCIPI