Design and fabrication of 1.3nm InGaAsP/InP DH LED with a monolithic integral lens

which exhibits high-speed performance

have been presented.Dependences of operating characteristics

such as the coupled power

the far field radiation patterns and the cut-off frequency on the LED and fiber structure parameters

have been analyzed and applied to complete an optimal design. LED's coupled to graded fiber with 50μm core

0.2NA were fabricated at the wavelength of 1.3μm. A significant improvement has been achieved particularly in the cut-off frequency and the maximum value of 425MHz at 150mA has been realized.Remarkable improvement in the coupling efficiency is demonstrated.