Patent ID: 7209775

Claim:
An apparatus for measuring a bio signal, comprising: a bio signal measurement unit, which is insertable into an ear to be in close contact with an internal surface of the ear, the bio signal measurement unit having a photo-plethysmography (PPG) measurement module for radiating light of different wavelengths onto the internal surface of the ear, detecting light transmitted through the ear, and outputting a PPG signal including bio information; a control unit having a PPG signal processor for generating the bio information using the PPG signal measured by the PPG measurement module and a sound processor for simultaneously outputting a sound signal without any bio information signal interference, wherein the control unit outputs the bio information when a signal received by the control unit corresponds to the bio information, and outputs the sound signal when a signal received by the control unit corresponds to the sound signal; an output unit for displaying the bio information generated from the control unit; and an earphone connected to the control unit for outputting the sound signal received from the control unit, wherein the control unit further includes a sound processor for controlling the volume of the sound signal.