title: Fabrication and simulation of diffractive optical elements with superimposed antireflection subwavelength gratings.
abstract: With the aim of reducing surface reflections and increasing the diffraction efficiency we investigated the superposition of subwavelength phase gratings onto blazed phase gratings. With direct-write electron-beam lithography bare blazed gratings and blazed gratings carrying subwavelength gratings were fabricated and their optical performances compared. For TE polarization the subwavelength-carrying gratings showed a maximum diffraction efficiency of 90.6%, whereas the corresponding maximum value for the bare grating was 86.3%. The experiment was simulated with rigorous diffraction theory.
authors: Angstrom Laboratory, Uppsala University, P.O. Box 534, SE-751 21 Uppsala, Sweden.
authors: F
authors: F
authors: Nikolajeff
authors: B
authors: B
authors: Löfving
authors: M
authors: M
authors: Johansson
authors: J
authors: J
authors: Bengtsson
authors: S
authors: S
authors: Hård
authors: C
authors: C
authors: Heine