HIGHER-ORDER KINOFORM LENSES - DIFFRACTION EFFICIENCY AND ABERRATIONAL PROPERTIES

The higher order kinoform lens is a diffractive imaging lens for which the optical path length transitions between neighboring zones is an i ntegral multiple of the design wavelength. Convenient expressions for diffraction efficiency, Seidel aberrations, and spherical aberrations of different orders are derived. It is observed that, when a p'th orde r kinoform lens with design wavelength lambda(0) is used with an illum ination having bandwidth Delta lambda around a midwavelength lambda, t he key parameter in determining the diffraction efficiency and aberrat ional properties at m'th diffraction order is the ratio R = (m lambda/ p lambda(0)). (C) 1997 Society of Photo-Optical Instrumentation Engine ers.