Multilevel phase holograms manufactured by electron-beam lithography.

Ten-level transmission phase holograms (kinoforms) manufactured in one resist layer by electron-beam lithography are reported for the first time to our knowledge. The measured hologram diffraction efficiencies were 70% for the two resist materials used. This corresponds to 82% of the maximum theoretical value for these holograms and is, to our knowledge, the highest reported to date.