Card reader and foreign matter detection method

A card reader for use with a card, the card reader comprising:

• a main body part comprising a card conveyance path in which the card inserted from an insertion port is conveyed;
• a first card detection mechanism disposed upstream of the main body part in an insertion direction of the card and structured to detect the card;
• a second card detection mechanism disposed in the main body part at a distance less than a length of the card in the insertion direction from the first card detection mechanism and structured to detect the card;
• a shutter member disposed between the first card detection mechanism and the second card detection mechanism and structured to move between a closed position to close the card conveyance path and an open position to open the card conveyance path;
• a shutter state detector structured to detect a state of the shutter member;
• and
• a control unit structured to:
• control the shutter member to move to the closed position when an object inserted from the insertion port is detected by the second card detection mechanism after the inserted object is detected by the first card detection mechanism, and then the inserted object is not detected by the second card detection mechanism at a timing when the inserted object is not detected by the first card detection mechanism;
• and
• detect that an object other than the card has been inserted when the shutter state detector detects that the shutter member does not move to the closed position after the control.