ENERGY CONSTRAINTS IN OPTIMUM APODIZATION PROBLEMS

[摘要] It is shown that the conventional energy constraint applied to optimum apodization problems is inappropriate for systems with large numerical apertures. In such cases, the total energy flux should be held fixed rather than the total intensity, which is the usual constraint. For comparison, Luneburg's first apodization problem is reexamined with each of these two constraints. It is proven that, when the total energy flux is fixed, a uniform converging spherical wave provides the optimum solution. This result contradicts earlier claims concerning the advantages of the so-called ''perfect wave'' over a uniform spherical wave.

[发布日期] 1994-08-15