Power equalization with optical feedback in a 52 wavelength SOA ring laser source

In summary, we have demonstrated a simple and stable, multi-wavelength laser source. It combines two semiconductor optical amplifiers and a fiber Fabry-Perot filter to generate 52 simultaneously oscillating wavelengths across 21 nm with a flat output spectrum. The power equalization and the broadening of the oscillating spectrum was achieved by means of adjusted, single-pass optical feedback of its output back into the source. The power standard deviation between the lines is less than 0.3 dB, the extinction between them was greater than 32 dB and their linewidth was calculated to be 500 MHz. The source may be useful as a relatively inexpensive source for passive and active component characterization.