A three-dimensional common-path interferometer is proposed, which can achromatically null out an on-axis source while it maintains the detectability of an off-axis source. A geometric phase in the three-dimensional interferometer introduces an achromatic pi-phase shift to the light from the on-axis source, such that destructive interference nulls out the axial light at one of the ports of the interferometer. Light from the off-axis source, which is exempt from the pi-phase shift, comes out from both ports with equal intensity. The common-path scheme makes the system highly immune to environmental disturbances.
© 2005 Optical Society of America
Alexander V. Tavrov, Yosuke Kobayashi, Yosuke Tanaka, Tatsutoshi Shioda, Yukitoshi Otani, Takashi Kurokawa, and Mitsuo Takeda, "Common-path achromatic interferometer-coronagraph: nulling of polychromatic light," Opt. Lett. 30, 2224-2226 (2005)