Electromagnetic theory of gratings: some advances and some comments on the use of the operator formalism

We first briefly draw the reader’s attention to some of our papers recently published in other journals. Then, after some comments on the admittance and impedance operators, we introduce the Calderon projectors, and we show how the operator formalism can be used in grating problems. Finally, we present theoretical considerations on total sequences in function spaces, and we discuss a numerical method that seems promising.