  The far-field pattern of a simple one-dimensional laser array of emitters
radiating into free space is considered. In the path of investigating the
inverse problem for their near fields leading to a target beam form,
surprisingly we found that the result is successful when the matrix of the
corresponding linear system is not well-scaled. The essence of our numerical
observations is captured by an elegant inequality defining the functional range
of the optical distance between two neighboring emitters. Our finding can
restrict substantially the parametric space of integrated photonic systems and
simplify significantly the subsequent optimizations.
