Hemispherical large-area surface-emitting SH GaAlAs LED with very low nonlinear distortion characteristics

A large-area surface-emitting SH GaAlAs LED is fabricated with the aim of reducing optical nonlinear distortion. A drastic reduction of the second-harmonic distortion level due to a compensation effect is confirmed at the position of maximum fiber input power. The developed LED exhibits -61-dB second-harmonic and -57-dB third-harmonic distortion levels under a 100-mA bias current and 50-percent modulation depth.