Now showing 1 - 2 of 2
No Thumbnail Available
Publication

Dielectric binary blazed gratings

1993-08-01, Haidner, H., Sheridan, John T., Streibl, N.

Artificial index gratings, which are composed of binary microstructures of sizes less than the incident wavelength, are analyzed as functions of the filling factor or duty cycle of the microstructures. Different models for calculating the optimum duty cycles to produce high blazed diffraction efficiency are compared. Blazed binary grating designs in a material with a refractive index n = 2 show theoretical diffraction efficiencies as high as η = 80%. In the semiconductor material silicon, which has a refractive index n = 3.4, theoretical diffraction efficiencies as high as η = 70% are predicted.

No Thumbnail Available
Publication

Binary blazed reflection gratings

1994-06-01, Collischon, M., Haidner, H., Kipfer, P., Lang, A., Sheridan, John T., Schwider, J., Streibl, N., Lindolf, J.

A reflection grating with a binary surface profile is presented that has high diffraction efficiency. The measured intensity for the + 1st diffracted order was 77%. The binary grating is composed of a minilattice with feature sizes comparable with the wavelength of the incident light. The overall structure is designed in such a way that it imitates a conventional blazed grating. The grating also has interesting polarization properties. The main part of the TE-polarized light is diffracted into the 1st diffracted order, and most of the TM-polarized light remains in the 0th diffracted order. The measurements of the grating are compared with rigorous diffraction theory and found to be in reasonable agreement.