Parameter-tolerant binary gratings.
A normalized modal analysis of binary gratings under normal TE incidence involving the most condensed set of optogeometrical parameters gives a complete solution to the problem of canceling the 0(th) transmitted order in phase masks of a low-to-high refractive index ratio down to 0.5 with a large tolerance on the corrugation duty cycle or a large spectral bandwidth. The solution is presented in the form of single normalized 3D charts which shed light on the fulfillment of the 0(th)-order cancellation condition: balanced excitation and π-phase difference between two grating modes. Examples of tolerant gratings are given.
Université de Lyon, Laboratoire Hubert Curien, UMR CNRS 5516, 18 rue du Professeur Benoît Lauras, F-42000,Saint-Etienne, France. thomas.kampfe@univ-st-etienne.fr
Thomas
T
Kämpfe
Olivier
O
Parriaux