Portable device

A portable device, comprising:

• a plurality of modules each of which has a battery, an individual function unit configured to operate by electric power stored in the battery and exhibit individual functions, and a short range communication unit configured to perform authentication processing through non-contact communication;
• wherein at least one of the plurality of modules includes an authentication power supply module;
• and wherein, when a first module and a second module, among the plurality of modules, perform authentication processing through non-contact short range communication, the authentication power supply module supplies electric power for authentication operation to at least one of the first module and the second module.

An electric power supply method performed by a portable device including a plurality of modules each of which has a battery, an individual function unit configured to operate by electric power stored in the battery and exhibit individual functions, and a short range communication unit configured to perform authentication processing through non-contact communication,

• wherein, when a first module and a second module of the plurality of modules perform authentication processing through non-contact short range communication, the first module detects remaining capacity of its own battery;
• and wherein, when the remaining capacity surpasses a predetermined level, electric power for use in performing authentication operation is supplied to the second module.

An electric power supply method performed by a portable device including a plurality of modules each of which has a battery, an individual function unit configured to operate by electric power stored in the battery and exhibit individual functions, and a short range communication unit configured to perform authentication processing through non-contact communication,

• wherein at least one of the plurality of modules includes an authentication power supply module;
• and wherein, when a first module and a second module, among the plurality of modules, perform authentication processing through non-contact short range communication, the authentication power supply module supplies electric power for authentication operation to both the first module and the second module or either of them.

A module for use in a portable device including:

• a plurality of modules each of which has a battery, an individual function unit configured to operate by electric power stored in the battery and exhibit individual functions, and a short range communication unit configured to perform authentication processing through non-contact communication,
• wherein remaining capacity of a battery of one module is detected when authentication of another module is performed;
• and wherein, when the remaining capacity surpasses a predetermined level, electric power for performing authentication operation is supplied to the other module.

A module for use in a portable device including:

• a plurality of modules each of which has a battery, an individual function unit configured to operate by electric power stored in the battery and exhibit individual functions, and a short range communication unit configured to perform authentication processing through non-contact communication,
• wherein, when a first module and a second module other than a module of interest perform authentication processing through non-contact short range communication, electric power for authentication operation is supplied to at least one of the first module and the second module.