The present invention provides a method and apparatus for using light emitting diodes for curing and various solid state lighting applications. The down hole casting assembly includes a mold and a blank coupled to the mold. The first phase difference plate 13 is a uniaxial phase difference plate which has a negative refractive index anisotropy, in which the phase difference value in the thickness direction is set in a range of from 220 nm to 1,320 nm, and which has the optical axis perpendicular to first and second glass substrates 4, 5 between which a liquid crystal layer 8 is interposed. The device is stable in a first configuration and a second configuration.