Idealized Grating Functions

The idealized grating function works without information about the actual shape of the grating structure. In the spatial frequency (k) domain, it defines

• the position (in k domain) of the diffraction orders according to the grating equation, and
• the effective B-matrix for each order according to a desired diffraction efficiency.

The relationship between the position of an arbitrary diffraction order and that of the input is governed by the grating equation. For a specific order, to connect the outgoing electromagnetic field quantities with the incoming ones, a 2×2 B-matrix is needed. An idealized method is used to define such an effective B-matrix from a given diffraction efficiency.