title: Wide-band coronagraph with sinusoidal phase in the angular direction.
abstract: We suggest a new phase mask coronagraph that can work in a wide band of wavelengths. The phase mask has alternatively sinusoidal and uniform functions in the angular direction. We compare it with the four-quadrant phase mask coronagraph and vortex phase mask coronagraph. Through numerical tests, we find that the new mask gives a deep extinction of star light and has a small inner working angle. It is also shown that this mask has a better performance in chromatism than the others for a wide band of wavelengths.
authors.affiliation: Department of Physics, Shanghai University, Baoshan District, Shanghai, China.
authors.forename: Ourui
authors.initials: O
authors.lastname: Ma
authors.forename: Qing
authors.initials: Q
authors.lastname: Cao
authors.forename: Fanzhen
authors.initials: F
authors.lastname: Hou
mesh_terms: D000465:Algorithms; D003116:Color; D007368:Interferometry / Q000379:methods*; D008027:Light; D015233:Models, Statistical; D008962:Models, Theoretical; D013026:Space Flight; D013055:Spectrophotometry, Infrared / Q000379:methods