A monolithically integrated smart pixel consisting of a photoconductive receiver and a non-resonant cavity LED

Summary form only. We present a concept for the monolithic integration of a special photoconductive receiver with a high efficiency LED, leading to a simple but powerful smart pixel device. The receiver of this smart pixel consists of a n-i-p reference diode in series with a specially designed photoconductive n-i-p detector. A common bias voltage U/sub sw/ is applied across both diodes. Since the photoconductive detector is basically a combination of a n-i-p photodiode and a back-gated field-effect transistor, the n-channel on top of the detector can be depleted by applying a sufficiently negative bias across the pn-junction. Under illumination (/spl lambda/=785 nm) the common bias voltage U/sub sw/ will drop across that diode which receives less optical power. Thus, the output current of the receiver can be controlled by the illumination of the two input diodes.