Patent ID: 8867064

Claim:
An image forming apparatus comprising: a display unit displaying operation information; an input unit receiving a user's command to use a function of the image forming apparatus in response to touching thereon by the user; an electrode disposed on a surface of said input unit to be touched by the user; a human-body communication unit electrically connected to said electrode, said human-body communication unit being adapted to read user information from a portable device worn by the user, in response to the user's input of a command for a function, wherein said human-body communication unit reads again the user information from the portable device when the user inputs a command for a different function; a storage unit storing authentication information defining whether or not use of each function incorporated in said image forming apparatus is allowed, in association with said user information; and a control unit, wherein said control unit is operative to: identify a commanded function and read said user information from said portable device, when said user's command is inputted, determine whether or not the use of said identified commanded function is allowed for said user information read from said portable device worn by the user who inputted said command, by making reference to said authentication information, provide said commanded function to the user, when the use of said commanded function is allowed, and invalidate said user's command, when the use of said commanded function is not allowed; and wherein said input unit is configured integrally with said display unit, said display unit displays a plurality of display areas each including independent operation information and authentication, and said control unit is further operative to: determine whether or not which of said plurality of display areas has been selected when the user touches said input unit, and perform authentication based on said user information, according to the operation information corresponding to said selected display area, independently of the user's command generated to the other display area.