Patent ID: 7522938

Claim:
A portable information terminal apparatus, comprising first and second circuit blocks capable of transmitting a signal between each other, and a switching device, wherein: said first circuit block comprising: a first optical signal transmitting/receiving device which converts an electric signal into an optical signal for transmitting it to said second circuit block and also converts an optical signal received from said second circuit block into an electric signal, and a first electric signal transmitting/receiving device which transmits an electric signal to said second circuit block and also receives an electric signal from said second circuit block; said second circuit block comprising: a second optical signal transmitting/receiving device which converts an electric signal into an optical signal for transmitting it to said first circuit block and also converts an optical signal received from said first circuit block into an electric signal, and a second electric signal transmitting/receiving device which transmits an electric signal to said first circuit block and also receives an electric signal from said first circuit block; and said switching device switches optical signal communication form achieved by said first and second optical signal transmitting/receiving devices and electric signal communication form achieved by said first and second electric signal transmitting/receiving devices according to a signal transmission amount between said first and second circuit blocks.