  Wire-grid polarizer sheets in the terahertz region have been fabricated on
flexible substrates by nanoimprint technology. They show ideal polarization
property in the terahertz frequency region whereas the cost is very low. Since
the wire pitch is far smaller than the wavelength, the effective medium theory
agrees well with experimental results. The effective medium theory shows
possibility of further improvement of polarization properties by selecting
appropriate materials for wire grids.
