Image reading apparatus and image reading method

An image reading apparatus configured to read an image on an original document that is sandwiched by a carrier sheet including a joint where peripheral portions of two sheets for sandwiching the original document are joined, the image reading apparatus comprising:

• a transport unit configured to transport the carrier sheet;
• a reading unit configured to read the image on the original document sandwiched by the carrier sheet transported;
• a carrier sheet detecting unit located upstream of the reading unit in a transport direction, and configured to detect the carrier sheet transported;
• and
• a control unit configured to determine that the carrier sheet is transported based on a detection result of the carrier sheet detecting unit or a reading result of the reading unit, wherein
• the control unit is configured to switch between adopting the detection result of the carrier sheet detecting unit and adopting the reading result of the reading unit,
• the carrier sheet includes a transmissive opening portion and a light-shielding portion having light-shielding properties at the joint, and
• the control unit determines that the carrier sheet is transported, based on the detection result by the carrier sheet detecting unit detecting the opening portion and the light-shielding portion, or the reading result by the reading unit reading the opening portion and the light-shielding portion.

An image reading apparatus configured to read an image on an original document that is sandwiched by a carrier sheet including a joint where peripheral portions of two sheets for sandwiching the original document are joined, the image reading apparatus comprising:

• a transport unit configured to transport the carrier sheet;
• a reading unit configured to read the image on the original document sandwiched by the carrier sheet transported;
• a carrier sheet detecting unit located upstream of the reading unit in a transport direction, and configured to detect the carrier sheet transported;
• a multi-feeding detecting unit configured to detect multi-feeding of an original document transported by the transport unit;
• and
• a control unit configured to determine that the carrier sheet is transported based on a detection result of the carrier sheet detecting unit or a reading result of the reading unit, wherein
• the control unit is configured to switch between adopting the detection result of the carrier sheet detecting unit and adopting the reading result of the reading unit,
• the control unit determines multi-feeding of the original document based on a detection result of the multi-feeding detecting unit when the control unit determines that the carrier sheet is transported based on the detection result of the carrier sheet detecting unit,
• the control unit determines multi-feeding of the original document based on the reading result of the reading unit when the control unit determines that the carrier sheet is transported based on the reading result of the reading unit,
• the control unit reports an error, when the control unit determines that multi-feeding of the original document occurs, and
• the control unit does not determine multi-feeding of the original document, when the control unit determines that the carrier sheet is transported, and
• a first period is shorter than a second period, where
• the first period is a period in which the original document is transported, multi-feeding of the original document is determined, and the error is reported, when the control unit determines that the carrier sheet is transported based on the detection result of the carrier sheet detecting unit, and
• the second period is a period in which the original document is transported, multi-feeding of the original document is determined, and the error is reported, when the control unit determines that the carrier sheet is transported based on the reading result of the reading unit.