  High-contrast imaging techniques now make possible both imaging and
spectroscopy of planets around nearby stars. We present the optical design for
the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS), a
lenslet-based, cryogenic integral field spectrograph (IFS) for imaging
exoplanets on the Subaru telescope. The IFS will provide spectral information
for 138x138 spatial elements over a 2.07 arcsec x 2.07 arcsec field of view
(FOV). CHARIS will operate in the near infrared (lambda = 1.15 - 2.5 microns)
and will feature two spectral resolution modes of R = 18 (low-res mode) and R =
73 (high-res mode). Taking advantage of the Subaru telescope adaptive optics
systems and coronagraphs (AO188 and SCExAO), CHARIS will provide sufficient
contrast to obtain spectra of young self-luminous Jupiter-mass exoplanets.
CHARIS will undergo CDR in October 2013 and is projected to have first light by
the end of 2015. We report here on the current optical design of CHARIS and its
unique innovations.
