We present a vacuum window mechanism that is useful for applications requiring two different vacuum windows in series, with one of them movable and resealable. Such applications include space borne instruments that can benefit from a thin vacuum window at low ambient pressures but must also have an optically open aperture at atmospheric pressures. We describe the implementation and successful operation with the E and B experiment balloon-borne payload, a millimeter-wave instrument designed to measure the polarization of the cosmic microwave background radiation.
Bibliographical noteFunding Information:
Support for the development and flight of the EBEX instrument was provided by NASA Grant Nos. NNX12AD50G, NNX13AE49G, NNX08AG40G, and NNG05GE62G and by NSF Grant Nos. AST-0705134 and ANT-0944513. Zilic acknowledges support by the Minnesota Space Grant Consortium. We are grateful to Suzanne Staggs for providing the original XPER window upon which our design was based. We thank Xin Zhi Tan for help with the figures.
© 2017 Author(s).