Abstract

Diffraction optics, i.e. Fresnel zone plates, holograms and diffraction gratings, has a limited application in the optical wavelength range. A decrease in wavelength to 100 nm and less changes conventional relationships between different types of optical elements owing to the change in the radiation-substance interaction since absorption starts to play a more important role as compared to refraction. Therefore at 1 nm≲λ≲100nm focusing elements may be fabricated only from thin membranes di stinguished by an abrupt change of either absorption (amplitude zone plates) or transmitted wave phase (phase zone plates).

© 1988 Optical Society of America