A multifrequency laser (MFL) eliminates nonlinearities produced in the "shared" waveguide of the MFL laser (the section in which all the lightwaves from all the lasers pass) by either making the shared waveguide as short as possible to mimimize the production of mixing product signals or using a channel spacing that is unequal such that any mixing product signals formed from the multifrequency optical laser signal do not overlap in frequency with any of the signals of the multifrequency optical laser signal.