Prospects of highly efficient AlGaInP based surface emitting type ring-LED for 50 and 156 Mb/s POF data link systems

The detail design and performance of the surface emitting type visible light emitting diode (LED) is described for using in the plastic optical fiber (POF)-based data links. The diode showed brightness as high as 3.5 mW @ 100 mA (de) and also exhibited the beam divergence angle as low as 10 degrees with using of well designed plastic lens. The using of LED with plastic lens helps to attain also the coupling efficiency over 70% with POF. The temperature rise of the ring LED under operation is also estimated to be 9 and 6 degrees C less than the conventional diode at 50 and 35 mA bias currents, respectively, Transmission experiments reveal that the diode is suitable for 50 and 156 Mb/s 100 m POE-based data links.