SPATIAL PARAMETRIC CHARACTERIZATION OF GENERAL POLYCHROMATIC-LIGHT BEAMS

The ABCD law and the M-2 factor are generalized for the propagation of general polychromatic light beams through first-order optical systems by introducing a generalized complex radius of curvature Q, an averag e wavelength <(lambda)over bar> and a characterization width W-C. The real part and the imaginary part of the parameter 1/Q are related to t he effective radius of curvature and the characterization width W-C re spectively. The characterization width W-C and the generalized M-2 fac tor are shown to be appropriate for describing the propagation capabil ity and the beam quality of a general polychromatic light beam respect ively. Moreover, the relation M-2 greater than or equal to 1 is deduce d, a novel approach for interpreting the physical meaning of the effec tive radius of curvature is presented, and several special examples su ch as the polychromatic diffraction-limited light beams are analysed. (C) 1997 Elsevier Science B.V.