Electronic endoscope apparatus which superimposes signals on power supply

An electronic endoscope apparatus comprising:

• an electronic endoscope equipped with an image pickup device;
• a main unit which is connected with the electronic endoscope and includes a processor unit;
• a common power/signal line which connects the electronic endoscope with the main unit;
• a power supply circuit which is installed in the main unit and supplies power to the electronic endoscope via the common power/signal line;
• a scope-side waveform superimposing circuit which superimposes a video signal obtained by the image pickup device on power transmitted through the common power/signal line and superimposes scope-side reference pulses on a predetermined blanking period in the video signal;
• a processor-side waveform superimposing circuit which superimposes processor-side reference pulses on a predetermined blanking period that occurs in the video signal supplied through the common power/signal line and that is not superimposed with the scope-side reference pulses;
• a processor-side separating circuit which separates the video signal and scope-side reference pulses superimposed on the common power/signal line;
• a processor-side synchronizing signal generating circuit which forms a signal synchronized with the scope-side reference pulses outputted from the processor-side separating circuit;
• a scope-side separating circuit which separates the processor-side reference pulses superimposed on the common power/signal line;
• and
• a scope-side timing generator which forms a signal synchronized with the processor-side reference pulses outputted from the scope-side separating circuit.

An electronic endoscope apparatus comprising:

• an electronic endoscope equipped with an image pickup device;
• a main unit which is connected with the electronic endoscope and includes a processor unit;
• an electromagnetic coupler which electromagnetically connects the electronic endoscope and the main unit to supply electric power and signals;
• a power supply circuit which is installed in the main unit and supplies AC power to the electronic endoscope via the electromagnetic coupler;
• a power receiving circuit which is installed in the electronic endoscope and draws AC power through the electromagnetic coupler;
• a waveform superimposing circuit which superimposes a video signal obtained by the image pickup device on the power transmitted through the electromagnetic coupler and superimposes scope-side or processor-side reference pulses on a predetermined blanking period in a field or a frame of the video signal;
• a separating circuit which separates the video signal superimposed on the power transmitted through the electromagnetic coupler and scope-side or processor-side reference pulses;
• and
• a synchronizing signal generating circuit which forms a signal synchronized with the scope-side or processor-side reference pulses outputted from the separating circuit.