This paper suggests that the astronomical science data recorded with low F# telescopes for
applications requiring a known point spread function shape and those applications requiring instrument
polarization calibration may be compromised unless the effects of vector wave propagation are properly
modeled and compensated. Exoplanet coronagraphy requires “matched filter” masks and explicit designs
for the real and imaginary parts for the mask transmittance. Three aberration sources dominate image
quality in astronomical optical systems: amplitude, phase and polarization. Classical ray-trace aberration
analysis used today by optical engineers is inadequate to model image formation in modern low F# highperformance
astronomical telescopes. We show here that a complex (real and imaginary) vector wave
model is required for high performance, large aperture, very wide-field, low F# systems.
Self-induced polarization anisoplanatism (SIPA) reduces system image quality, decreases contrast
and limits the ability of image processing techniques to restore images. This paper provides a unique
analysis of the image formation process to identify measurements sensitive to SIPA. Both the real part and
the imaginary part of the vector complex wave needs to be traced through the entire optical system,
including each mirror surface, optical filter, and all masks. Only at the focal plane is the modulus squared
taken to obtain an estimate of the measured intensity.
This paper also discusses the concept of the polarization conjugate filter, suggested by the author
to correct telescope/instrument corrupted phase and amplitude and thus mitigate6, in part the effects of
phase and amplitude errors introduced by reflections of incoherent white-light from metal coatings.