  The photon production rate from the deconfined medium is analyzed with the
photon self-energy constructed from the quark propagator obtained by the
numerical simulation on the quenched lattice for two values of temperature,
$T=1.5T_{\rm c}$ and $3T_{\rm c}$, above the critical temperature $T_{\rm c}$.
The photon self-energy is calculated by the Schwinger-Dyson equation with the
lattice quark propagator and a vertex function determined so as to satisfy the
Ward-Takahashi identity. The obtained photon production rate exhibits a similar
behavior as the perturbative results at the energy of photons larger than
$0.5$~GeV.
