  With the continuous improvement in the precision of exoplanet observations,
it has become feasible to probe for subtle effects that can enable a more
comprehensive characterization of exoplanets. A notable example is the tidal
deformation of ultra-hot Jupiters by their host stars, whose detection can
provide valuable insights into the planetary interior structure. In this work,
we extend previous research on modeling deformation in transit light curves by
proposing a simple approach to account for tidal deformation in phase curves.
The planetary shape is modeled as a function of the second fluid Love number
for radial deformation $h_{2f}$. We show that the effect of tidal deformation
manifests across the full orbit of the planet as its projected area varies with
phase, thereby allowing us to better probe the planet's shape in phase curves
than in transits. Comparing the effects and detectability of deformation by
different space-based instruments, we find that the effect of deformation is
more prominent in infrared observations where the phase curve amplitude is the
largest. A single JWST phase curve observation of a deformed planet, such as
WASP-12b, can allow up to 17$\sigma$ measurement of $h_{2f}$ compared to
4$\sigma$ from transit-only observation. Such high precision $h_{2f}$
measurement can constrain the core mass of the planet to within 19\% of the
total mass, thus providing unprecedented constraints on the interior structure.
Due to the lower phase curve amplitudes in the optical, the other instruments
provide $\leq4\sigma$ precision on $h_{2f}$ depending on the number of phase
curves observed. We also find that detecting deformation from infrared phase
curves is less affected by uncertainty in limb darkening, unlike detection in
transits. Finally, the assumption of sphericity when analyzing the phase curve
of deformed planets can lead to biases in several system parameters
