Abstract
Reduction of laser diode noise was examined by using negative electrical feedback. A laser output noise level was reduced by 14dB in the frequency range below 22 MHz, but was increased above 22 MHz. The experimental result was in good agreement with a theory. The noise level in reading out a video disk was reduced by 3dB to the disk noise level without feedback, and the carrier-to-noise ratio was increased by 3dB consequently.
