Design of highly transparent glasses with broadband antireflective subwavelength structures.

We present a design optimization of highly transparent glasses with broadband antireflective subwavelength structures (SWS) based on the theoretical calculation using a rigorous coupled wave analysis method. It is found that optical transmission characteristics of SWS integrated glasses are governed mainly by the zero-order condition considering multiple internal reflections but not external reflection. By utilizing parabola-shaped SWS on both sides of the glasses with a period of 200 nm and a height of 200 nm, an average transmittance of 99.58% is achieved over a whole range of visible wavelength. Transmission band shrinkage effects of the SWS integrated glass are also observed with increasing the incident angle of light.