  In this paper we present an overview of the Telescope designed for ESA's
mission dedicated to map the Cosmic Microwave Background Anisotropies and
Polarization. Two instruments, LFI and HFI, operate in an overall frequency
range between 25 and 900 GHz and share the focal region of the 1.5 meter
optimized telescope. The optimization techniques adopted for the optical design
and the telescope characteristic are reported and discussed.
