Analysis and applications of optical diffraction by gratings

TLDR

Diffraction characteristics of general dielectric planar and surface‑relief gratings are reviewed, with applications to laser‑beam deflection, guidance, modulation, coupling, filtering, wavefront reconstruction, distributed feedback, acousto‑optics, integrated optics, holography, and spectral analysis discussed. An exact, approximation‑free formulation of grating diffraction—rigorous coupled‑wave theory—using state‑variable methods is presented, and shown to reduce to existing approximate theories under appropriate limits. The impact of the fundamental assumptions underlying approximate theories is quantified and discussed.

Abstract

Diffraction characteristics of general dielectric planar (slab) gratings and surface-relief (corrugated) gratings are reviewed. Applications to laser-beam deflection, guidance, modulation, coupling, filtering, wavefront reconstruction, and distributed feedback in the fields of acoustooptics, integrated optics, holography, and spectral analysis are discussed. An exact formulation of the grating diffraction problem without approximations (rigorous coupled-wave theory developed by the authors) is presented. The method of solution is in terms of state variables and this is presented in detail. Then, using a series of fundamental assumptions, this rigorous theory is shown to reduce to the various existing approximate theories in the appropriate limits. The effects of these fundamental assumptions in the approximate theories are quantified and discussed.