Efficient Linearly Polarized Lamp for Liquid Crystal Displays

We propose a new optical design to produce linearly polarized illumination for liquid crystal displays. The operation mechanism is based on polarization conversion due to induced surface plasmon polariton on metallic gratings in conical diffraction. This linearly polarized lamp integrates an unpolarized light source and a light recycling scheme inside the lamp housing. Its structure is simple and, moreover, its optical efficiency reaches 92% in emitting a linearly polarized light.