Broadband achromatic phase retarder based on metal-multilayer dielectric grating
Li Na1, 2, Kong Wei-Jin1, 3, †, Xia Feng1, Yun Mao-Jin1, 3
       

(color online) Effects of deviation of (a) groove depth, (b) duty cycle, and (c) incident angle on phase retardations of TE and TM waves.