Abstract
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 device and light-receiving device. In this study, each of a light emitting diode (LED) and a laser diode (LD) is used as the light-emitting device, and PINPD as the light-receiving device. Transcutaneous transmission characteristics of these optical couplers are measured and compared. As a result, it is found that, in the transcutaneous telemetry system used, the LD as a light-emitting device shows better transmission characteristics in the light-emitting efficiency and the permissible deviation caused by body motion, and also found that there is a optimum separation between the emitting device and the receiving device for the permissible deviation to be maximum
