  We have studied polarized image of a Schwarzschild black hole with an
equatorial thin accretion disk as photon couples to Weyl tensor. The
birefringence of photon originating from the coupling affect the black hole
shadow, the thin disk pattern and its luminosity distribution. We also analyze
the observed polarized intensity in the sky plane. The observed polarized
intensity in the bright region is stronger than that in the darker region. The
stronger effect of the coupling on the observed polarized vector appears only
in the bright region close to black hole. These features in the polarized image
could help us to understand black hole shadow, the thin accretion disk and the
coupling between photon and Weyl tensor.

General Relativity and Quantum Cosmology