  Polarimetry is one of the keys to enhanced direct imaging of exoplanets. Not
only does it deliver a differential observable providing extra contrast, but
when coupled with spectroscopy, it also reveals valuable information on the
exoplanetary atmospheric composition. Nevertheless, angular separation and
contrast ratio to the host-star make for extremely challenging observation.
Producing detailed predictions for exactly how the expected signals should
appear is of critical importance for the designs and observational strategies
of tomorrow's telescopes. We aim at accurately determining the magnitudes and
evolution of the main observational signatures for imaging an exoplanet:
separation, contrast ratio to the host-star and polarization as a function of
the orbital geometry and the reflectance parameters of the exoplanet. These
parameters were used to construct polarized-reflectance model based on the
input of orbital parameters and two albedo values. The model is able to
calculate a variety of observational predictions for exoplanets at any orbital
time. The inter-dependency of the three main observational criteria
-separation, contrast ratio, polarization- result in a complex time-evolution
of the system. They greatly affect the viability of planet observation by
direct imaging. We introduce a new generic display of the main observational
criteria, which enables an observer to determine whether an exoplanet is within
detection limits: the Separation-POlarization-Contrast diagrams (SPOC). We
explore the complex effect of orbital and albedo parameters on the visibility
of an exoplanet. The code we developed is available for public use and
collaborative improvement on the python package index, together with its
documentation. It is another step towards a full comprehensive simulation tool
for predicting and interpreting the results of future observational
exoplanetary discovery campaigns.
