An achromatic Fresnel optic that combines a Fresnel zone plate and a refractive
Fresnel lens. The zone plate provides high resolution for imaging and focusing,
while the refractive lens takes advantage of the refraction index change properties
of appropriate elements near absorption edges to recombine the electromagnetic
radiation of different energies dispersed by the zone plate. This compound lens
effectively solves the high chromatic aberration problem of zone plates. The AFO
has a wide range of potential applications in lithography, microimaging with various
contrast mechanisms and measurement techniques.
