High-efficiency subwavelength diffractive element patterned in a high-refractive-index material for 633 nm

Simion Astilean (1) , Philippe Lalanne (1) , Pierre Chavel (2) , Edmond Cambril (3) , Huguette Launois (3)

1 Laboratoire Charles Fabry de l'Institut d'Optique / Naphel
2 Laboratoire Charles Fabry de l'Institut d'Optique / Scop
3 L2M - Laboratoire de Microstructures et de Microélectronique

We propose the use of high-index materials for the fabrication of subwavelength diffractive components operating in the visible domain. This approach yields a reduction of fabrication constraints and an improvement of theoretical performance. A blazed grating with subwavelength binary features and with a period of 5.75 wavelengths is designed and fabricated in a TiO2 layer coated upon a glass substrate. The first-order diffraction efficiency measured with a He-Ne laser beam is 83%, which is slightly larger than that achieved theoretically by the best standard (continuous profile) blazed grating fabricated in glass with the same period.

Domains: Optics [physics.optics]

Simion Astilean, Philippe Lalanne, Pierre Chavel, Edmond Cambril, Huguette Launois. High-efficiency subwavelength diffractive element patterned in a high-refractive-index material for 633 nm. Optics Letters, 1998, 23 (7), pp.552-554. ⟨10.1364/OL.23.000552⟩. ⟨hal-00877412⟩