Anti Reflection structures:
Example of bi-dimensional glass made gratings
Data
Glass Refractive index ns = 1.52
Supertrate medium Air n = 1.
Grating periods: 2 x 250nm
Grating depth 250nm
Rigorous calculation with 49 coupled waves
Normal Incidence
Theoretical
Reflectance (rigorous method)
with normal incidence
Transmittance
mapping of structure 3 Vs wavelength
(from 380nm to 780nm) and angle of incidence (from 0 to 45 deg)
The lossed energy is located
into the substrate propagative waves
(+/- 1 transmission order) or in the specular reflected zero order.