A pulse oximeter, comprising: a light emitting device configured to emit white light to irradiate a blood vessel; and a sensor comprising separate unit pixels and configured to detect transmitted light that is received from the light emitting device, subsequently to the transmitted light having irradiated the blood vessel, the sensor including a near infrared organic photoelectric conversion device configured to sense a particular near infrared wavelength spectrum of light, and a red photoelectric conversion device configured to sense a particular red wavelength spectrum of light, characterized in that: the near infrared organic photoelectric conversion device is formed of a combination of a near infrared organic photoelectric conversion layer on a semiconductor substrate and a common electrode disposed on the near infrared organic photoelectric conversion layer, and a pixel electrode formed for each separate unit pixel is between the near infrared organic photoelectric conversion layer and the semiconductor substrate and in contact with the near infrared organic photoelectric conversion layer; each separate unit pixel includes a separate photoelectric conversion device (550r, 550g, 550r) and a separate pixel electrode overlapped with a separate portion of the near infrared organic photoelectric conversion layer and the common electrode; and each pixel electrode is connected with a charge accumulator through a contact filled in a via formed in an interlayer insulating layer. a light emitting device configured to emit white light to irradiate a blood vessel; and a sensor comprising separate unit pixels and configured to detect transmitted light that is received from the light emitting device, subsequently to the transmitted light having irradiated the blood vessel, the sensor including a near infrared organic photoelectric conversion device configured to sense a particular near infrared wavelength spectrum of light, and a red photoelectric conversion device configured to sense a particular red wavelength spectrum of light, a near infrared organic photoelectric conversion device configured to sense a particular near infrared wavelength spectrum of light, and a red photoelectric conversion device configured to sense a particular red wavelength spectrum of light, characterized in that: the near infrared organic photoelectric conversion device is formed of a combination of a near infrared organic photoelectric conversion layer on a semiconductor substrate and a common electrode disposed on the near infrared organic photoelectric conversion layer, and a pixel electrode formed for each separate unit pixel is between the near infrared organic photoelectric conversion layer and the semiconductor substrate and in contact with the near infrared organic photoelectric conversion layer; each separate unit pixel includes a separate photoelectric conversion device (550r, 550g, 550r) and a separate pixel electrode overlapped with a separate portion of the near infrared organic photoelectric conversion layer and the common electrode; and each pixel electrode is connected with a charge accumulator through a contact filled in a via formed in an interlayer insulating layer. the near infrared organic photoelectric conversion device is formed of a combination of a near infrared organic photoelectric conversion layer on a semiconductor substrate and a common electrode disposed on the near infrared organic photoelectric conversion layer, and a pixel electrode formed for each separate unit pixel is between the near infrared organic photoelectric conversion layer and the semiconductor substrate and in contact with the near infrared organic photoelectric conversion layer; each separate unit pixel includes a separate photoelectric conversion device (550r, 550g, 550r) and a separate pixel electrode overlapped with a separate portion of the near infrared organic photoelectric conversion layer and the common electrode; and each pixel electrode is connected with a charge accumulator through a contact filled in a via formed in an interlayer insulating layer.