  We present a metamaterial-based random polarization control plate to produce
incoherent laser irradiation by exploiting the ability of metamaterial in local
polarization manipulation of beam upon transmission via tuning its local
geometry. As a proof-of-principle, we exemplify this idea numerically in a
simple optical system using a typical L-shaped plasmonic metamaterial with
locally varying geometry, from which the desired polarization distribution can
be obtained. The calculating results illustrate that this scheme can
effectively suppress the speckle contrast and increase irradiation uniformity,
which has potential to satisfy the increasing requirements for incoherent laser
irradiation.
