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We present the status of the development of a coronagraph for the Space Infrared telescope for Cosmology and
Astrophysics (SPICA). SPICA is the next generation of infrared space-borne telescope missions following to AKARI,
led by Japan. SPICA will carry a telescope that has a 3.5 m diameter monolithic primary mirror and the whole telescope
will be cooled to 4.5 K. It is planned to launch SPICA into the sun-earth L2 libration halo orbit using H II-A rocket in the
middle of the 2010s and execute infrared observations at wavelengths mainly between 5 and 200 micron. The SPICA
mission gives us a unique opportunity for coronagraph observations, because of the large telescope aperture, the simple
pupil shape, the capability of infrared observations from space, and the early launch. We have started development of the
SPICA coronagraph in which the primary target is direct observation of extra-solar Jovian planets. The main
wavelengths of observation, the required contrast and the inner working angle (IWA) of the SPICA coronagraph
instrument are set to be 5-27 micron, 10-6, and a few λ/D (and as small as possible), respectively, in which λ is the
observation wavelength and D is the diameter of the telescope aperture (3.5m). We focused on a coronagraph with a
binary shaped pupil mask as the primary candidate for SPICA because of its feasibility. Nano-fabrication technology
using electron beam lithography was applied to manufacture a high precision mask and a laboratory experiment with a
He-Ne laser (λ=632.8nm) was performed in air without active wavefront control. The raw contrast derived from the
average measured in the dark region reached 6.7×10-8. On the other hand, a study of Phase Induced Amplitude
Apodization (PIAA) was started in an attempt to achieve higher performance, i.e., smaller IWA and higher throughput. A
hybrid solution using PIAA and a shaped pupil mask was proposed. A laboratory experiment was performed using a He-
Ne laser with active wavefront control via a 32×32 channel deformable mirror. A raw contrast of 6.5×10-7 was achieved.
Designs of binary shaped pupil mask are presented for the actual SPICA pupil which is obstructed by the telescope's
secondary mirror and its support. Subtraction of point spread function (PSF) was also evaluated.
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