The existing high contrast imaging techniques cannot be applied
directly to the telescope of the diameter 30–100 m without taking
into account the specific characteristics of a segmented surface.
While the increase in telescope diameter is an advantage for the
high contrast range science, the segmentation sets a limit on the
performance of the coronagraph. In particular, diffraction from
intersegment gaps sets a floor to the achievable extinction of the
starlight. Masking out the gaps in the Lyot plane although helps
increasing the contrast, does not solve completely the problem: the
high spatial frequency component of the diffractive light remains.
In the paper I suggest using a Lyot stop which produces a
phase-amplitude modulation in order to reduce the effect of
segmentation.