Next Generation Vector Vortex Waveplates for Astronomical Coronagraphs

Vector vortex waveplates (VVWs) are highly promising technology enabling astronomical coronagraph masks for exoplanet imaging and characterization. Currently, the technology basics are well known, and there have been successful demonstrations of VVWs meeting several key operational requirements. The next generation of VVWs under development will make it possible to extend their spectral range of performance into infrared, further increase the contrast using novel materials, and would improve manufacturing to reduce cost. Yield and quality will be increased by eliminating internal and external sources of structural non-uniformities and defects and by employing novel minimally invasive manufacturing processes. Novel designs and device architectures to be developed in the Phase 2 of the project are intended to improve performance of VVWs to the levels that would not require polarization filtering thus increasing the throughput nearly twice. High contrast liquid crystal polymer broadband reflective VVWs to be developed wherein geometrical phase is insensitive to retardation would allow novel coronagraph architectures while minimizing dependence on process conditions and simplifying manufacturing. Furthermore, the next generation VVWs would allow reducing size and weight of coronagraphs by integrating VVW technology with other planar optics functions. The next generation of VVWs under development will make it possible to extend their spectral range of performance into infrared, further increase the contrast using novel materials, and would improve manufacturing to reduce cost. Yield and quality will be increased by eliminating internal and external sources of structural non-uniformities and defects and by employing novel non-invasive manufacturing processes. Novel designs and device architectures to be developed in the Phase 2 of the project are intended to improve performance of VVWs to the levels that would not require polarization filtering thus increasing the throughput nearly twice. High contrast liquid crystal polymer broadband reflective VVWs to be developed wherein geometrical phase is insensitive to retardation would allow novel coronagraph architectures while minimizing dependence on process conditions. The next generation VVWs would allow reducing size and weight of coronagraphs by integrating VVW technology with other optical functions. The Phase 2 of the project would allow overcoming the problems we are still facing in the fabrication of VVWs for advancing the technology into coronagraph applications and to the next generation characterized by: ultrahigh contrast; ultralow-scatter and defects; ultrabroadband spectra of high diffraction efficiency; spectra extended to SWIR-MWIR; polarization-independence; availability of transmissive as well as reflective systems; feasibility of combining multiple functions into a single thin film, and, making VVWs with higher yield and lower cost by developing robust VVW architectures that would eliminate or, at least, will dramatically reduce the effects of fabrication errors and ambient conditions on device performance. Meeting these objectives in the Phase 2 would require maturation of the breakthroughs in fabrication technology, some of them demonstrated in the Phase 1 of the project: direct assembly minimizing or fully avoiding release/transfer processes; fabrication VVWs on ultrathin glass; tuning retardation during and post-polymerization; enhancing automation level to ensure absence of defects and high quality for multiple coatings required for ultrabroadband and SWIR components; and, necessarily, ability to perform more of the key fabrication and test processes in higher purity and environmentally stabilized clean room.
Benefits: Astronomical coronagraphs, optical communications; quantum computing; super-resolution imaging Free-space optical communication; optical tweezers and micromanipulation; bio-sensors; quantum computing; image processing; Shaping of high power laser beams