Example of the Kogelnik efficiency curves for s- and p-polarization states. Δn_g is 0.145, and n₂ is 1.3. This grating is tuned at a DCG layer thickness of 9 μm for a wavelength of 1040 nm with 1400 fringes/mm and an (close to Bragg) incidence angle of α₂ = 34.55°. For this thickness, the diffraction efficiency for unpolarized light reaches near unity. This efficiency curve does not include potential reflection and absorption losses.