Proc. SPIE 7438, 74380O, 1−10, 2009
Solar Physics and Space Weather Instrumentation III
S. Fineschi and J.A. Fennelly (eds)
© SPIE − The International Society for Optical Engineering
Fabrication and test of a diamond-turned mirror suitable for a spaceborne photometric heliospheric imager
A. Buffington
Center for Astrophysics and Space Sciences, University of California San Diego
K.G. Bach, B.W. Bach and E.K. Bach
Bach Research Corp., USA
M.M. Bisi, P.P. Hick and B.V. Jackson
Center for Astrophysics and Space Sciences, University of California San Diego
P.D. Klupar
NASA Ames Research Cntr
Abstract
We have fabricated a diamond-turned low-mass version of a toroidal mirror which
is a key element for a spaceborne visible-light heliospheric imager. This
mirror's virtual image of roughly a hemisphere of sky is viewed by a
conventional photometric camera. The optical system views close to the edge of
an external protective baffle and does not protrude from the protected volume.
The sky-brightness dynamic range and background-light rejection requires minimal
wideangle scattering from the mirror surface. We describe the manufacturing
process for this mirror, and present preliminary laboratory measurements of its
wide-angle scattering characteristics.