  The scientific interest in directly image and identifying Earth-like planets
within the Habitable Zone (HZ) around nearby stars is driving the design of
specialized direct imaging mission such as ACESAT, EXO-C, EXO-S and AFTA-C. The
inner edge of Alpha Cen A and B Habitable Zone is found at exceptionally large
angular separations of 0.7 and 0.4 arcseconds respectively. This enables direct
imaging of the system with a 0.3m class telescope. Contrast ratios in the order
of 1e-10 are needed to image Earth-brightness planets. Low-resolution (5-band)
spectra of all planets, will allow establishing the presence and amount of an
atmosphere. This star system configuration is optimal for a specialized small,
and stable space telescope, that can achieve high-contrast but has limited
resolution. This paper describes an innovative instrument design and a mission
concept based on a full Silicon Carbide off-axis telescope, which has a Phase
Induce Amplitude Apodization coronagraph embedded in the telescope. This
architecture maximizes stability and throughput. A Multi-Star Wave Front
algorithm is implemented to drive a deformable mirror controlling
simultaneously diffracted light from the on-axis and binary companion star. The
instrument has a Focal Plane Occulter to reject starlight into a high-precision
pointing control camera. Finally we utilize a Orbital Differential Imaging
(ODI) post-processing method that takes advantage of a highly stable
environment (Earth-trailing orbit) and a continuous sequence of images spanning
2 years, to reduce the final noise floor in post processing to 2e-11 levels,
enabling high confidence and at least 90 percent completeness detections of
Earth-like planets.
