Transcutaneous photocoupler for transmission of biological signals.

A compact, photocouplerlike system is presented for wireless transcutaneous transmission of biological signals. The system consists of an optically powered near-infrared light transmitter, a receiver for the signals from it, and a near-infrared light source with which to irradiate it. The transmitter, which is implanted under the skin, is transcutaneously coupled with the receiver and the light source, which are combined and placed on the skin. The transmitter, which is powered transcutaneously by the light source, then amplifies a signal input to it and sends intensity-modulated light transcutaneously to the receiver. With this system, electromyograms and neuronal firing patterns of live rats have been successfully recorded.