  We investigate signatures of spin and orbital states of $R$VO$_{3}$ ($R$=Y
and La) in the optical conductivity using density functional theory plus
dynamical mean-field theory (DFT+DMFT). From the assignment of multiplet states
to optical transitions, DFT+DMFT reproduces experimental temperature dependent
evolutions of optical conductivity for both YVO$_{3}$ and LaVO$_{3}$. We also
show that the optical conductivity is a useful quantity to probe the evolution
of the orbital state even in the absence of spin order. The result provides a
reference to investigate spin and orbital states of ${t_{2g}}^{2}$ vanadate
systems which is an important issue for both fundamental physics on spin and
orbital states and applications of vanadates by means of orbital state control.
