A wide-angle metamaterial narrow-band-stop filter for 532 nm wavelength   green light
  Traditional optical interference narrow-band-stop filters do not possess wide-angle property, because peaks and troughs of filter spectrum would be moved at a non-normal angle of incidence (AOI), which could result in functional failure in particular cases, e.g. blocking of laser for pilot in cockpit during premeditated laser pointer direct. For this reason, we designed a wide-angle metamaterial narrow-band-stop filter assembled by cross shaped units to block 532 nm green light, which is firstly reported in the world. Unnecessary shift of spectrum caused by AOI change is effectively inhibited, and angular tolerance of wide-angle capability achieves to 35 degrees non-normal AOIs. 
Liyang Yue, Songkun Ji, Bing Yan, Nguyen Thanh Tung, Vu Dinh Lam and   Zengbo Wang
physics.optics