Sheet removal determination system and sheet removal determination method

A sheet removal determination method, comprising:

• detecting a sheet discharged to a discharge port;
• detecting a terminal device positioned within a communication enabled range;
• determining whether or not a user is an authorized user based on user information acquired from the terminal device;
• and
• determining that the sheet has been improperly removed if the user is not the authorized user and the terminal device is detected and a quantity of the sheets is less than that of the sheets before detection after the sheet is detected;
• and
• detecting terminal device positioned within a communication enabled range if the terminal device is detected and a quantity of the sheets is increasing than that of the sheets before detection after the sheet is detected.

An image forming apparatus, comprising:

• an image forming section;
• and
• a sheet removal determination system, comprising:
• a first detection device configured to detect a sheet discharged to a discharge port;
• a second detection device configured to detect a terminal device positioned within a communication enabled range of the second detection device;
• and
• a controller configured to
• determine whether or not a user is an authorized user based on user information acquired from the terminal device detected by the second detection device,
• determine that the sheet has been improperly removed if the user is not the authorized user and the second detection device detects the terminal device and a quantity of the sheets is less than that of the sheets before detection after the sheet is detected by the first detection device, and
• detect the terminal device again with the second detection device if the second detection device detects the terminal device and a quantity of the sheets is increasing than that of the sheets before detection after the sheet is detected by the first detection device.