Transcutaneous optical telemetry system-investigation on deviation characteristics

As a means of sending signals from the interior of a living body to the exterior, or vice versa, we have proposed a transcutaneous optical telemetry system (TOTS). As there is the skin between the transmitter and the receiver, light will be attenuated in it and the signal will be deteriorated. Therefore, careful examinations are necessary on the performances of the transcutaneous optical coupler, wavelength of the light used, directivities of the light-emitting element and light-receiving element. In this report, a light emitting diode (LED) and a laser diode (LD) are used as the light-emitting element. Transcutaneous transmission characteristics of these two elements are measured and compared. As a result, it is found that, in the transcutaneous telemetry system used, the LD shows better transmission characteristics