(two-mirror variant of three-mirror astigmat telescopes)
An Eisenberg-Pearson telescope is a type of two-mirror
reflector telescope which was described in 1987,
that effectively provides a three-mirror anastigmat design,
but with its specifically-shaped center of the
primary mirror serving in place of a third mirror.
Like three-mirror anastigmat telescopes,
it can reduce common aberrations,
while providing a flat focal plane.
The Rubin Observatory telescope has been termed an Eisenberg-Pearson telescope,
but I presume some consider the three-mirror-astigmat design
that describes it optically to be a more-useful categorization.