Broadband Vector Vortices for High Contrast Coronagraphy

Vector vortex waveplates (VVWs) have been shown to be useful for coronagraphy and other applications requiring proximity glare suppression. BEAM Co. has been on the forefront of development of VVWs for such applications, and is well-positioned to apply past experience to extending this technology into new regions of the spectrum, including the ultraviolet, and to make it possible to achieve high contrast in coronagraphy over broader wavelength bands than has to date been possible. Materials already proven to enable proximity glare suppression in the visible are readily adaptable to the UV at least down to 300 nm wavelength, and further material development should allow glare suppression for even shorter wavelengths. Multilayer liquid crystal polymer structures are expected to allow broadening of the spectral bandwidth over which high contrast is provided from 10% of the center wavelength to at least 20% of bandwidth. The design techniques to be developed under the program for new wavelength bands, and for broader operational bandwidths, are applicable to a wide range of diffractive waveplate devices in addition to VVWs, and to additional applications, including design of diffraction gratings for spectrometry, and design of telescopes based on diffractive waveplate structures.