Optimum Zone Plate Theory and Design

Abstract

Transmission zone plates composed of materials describable by the complex index of refraction ñ(ñ = (1 − δ)+ ik) modulate both the amplitude and phase of the light passing through them. In this monograph, a general variational approach to the design of zon plate profiles which maximize system transfer functions like I(m)/IIN or I(m)/IOUT (where IIN and IOUT are the total input and output powers and I(m) is the diffracted power of the mth order) is presented in terms of the real and imaginary components of ñ. The variational problem, as formulated here, is shown to generate some important classical zone plate configurations as special solutions and to lead naturally to the derivation of the most general zone plate configurations possible. Some specific optimum solutions are derived for gold in the soft x-ray range and tabulated for convenient reference.KeywordsZone PlateComplex IndexThickness ProfileOptimum ProfileFresnel Zone PlateThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.