الملخص

The experimental investigation of the influence of optical feedback on the pulse analysis of GaAlAs laser diode is represented, with an experimental setup designed for this purpose. Optical feedback was constructed with a plane mirror facing the facet of the laser diode at a distance of ( 16 cm ). Phase control and feedback rate were varied according to the external cavity length with the respect of laser diode cavity. Many benefits can be obtained from this research , to improve laser light output with increasing the external differential quantum efficiency by ( 0.7 %), arid threshold reduction by ( 0,5 mA ) with Optical feedback furthermore the experimental result indict that there was a peak shift of the pulse distribution of the laser output towards high frequency by feedback rale was increased. Laser wavelength tuning can be interpreted from there experimental results in additional to the improvement of spectral characteristics with the reduction of FWHM and increase in the intensity of laser output.