Patent ID: 7369312
Filing Date: 2008-05-06
Classification: G02B

Abstract:
1. A polarization converter for converting electromagnetic radiation from a source into electromagnetic radiation having a prescribed polarized radiation state, said radiation source providing electromagnetic radiation resolvable into a two mutually orthogonal linear polarization states, comprising: a plurality of alternating layers, the plurality of alternating layers including at least two layer types, one layer type having at least one of a high refractive index and birefringence, and polarization scattering capability, as compared to the other layer types, and one layer type having at least a low refractive index and no birefringent capability, as compared to the other layer types, the alternating layers having the at least one of a high refractive index and birefringence, and polarization scattering capability being adjacent at least one non-birefringent layer of low refractive index in an alternating arrangement of layer types defining interfaces between the layer types, the interfaces being arranged at an angle with respect to incoming electromagnetic radiation such that both reflection and refraction occurs at the interfaces, with one linear polarization state being preferentially reflected at the interfaces between layer types, with orthogonal polarization states being preferentially refracted at the said interfaces, one edge of each alternating layer being adjacent at an entrance aperture or adjacent to a micro-optic collector, the entrance aperture thus comprising a series of adjacent micro-optic entrance apertures, each defined by a cross-section of an alternating layer at the entrance aperture, or series of micro-optic collectors, one other edge of each alternating layer also being adjacent an exit aperture or series of micro-optic reflectors, the exit aperture thus comprising a series of adjacent micro-optic exit apertures, each defined by a cross-section of a layer at the exit aperture, or a micro-optic reflector, with said low and high refractive indices being related so as to cause polarization separation, reflection, refraction, and channeling of said two mutually orthogonal linear polarization states, and where at least one layer is a radiation conduit favoring reflection of a selected polarization state and transmitting radiation to the exit aperture, and where at least one layer is a radiation polarization converter causing refracted radiation to be of randomized electric field radiation vectors, and to refract said refracted radiation out of a major side of the layer having at least one of a high refractive index and birefringence, and polarization scattering capability into an adjacent non-birefringent layer, with at least one of a high refractive index and birefringence, and polarization scattering capability being constructed and randomly positioned with respect to the birefringent electric field radiation vector rotation of desired polarization states, with, for optimum polarization conversion performance, the said angled layers are angled at angles other than Brewster's angle with respect to incident radiation utilizing more than one reflection refraction interaction, in accordance with Malus's law, and the multiple reflection refraction interactions providing higher conversion efficiency than available with orientation at Brewster's angle with two or less reflection refraction interactions, with said polarization converter optimizing polarization conversion using greater than one reflection refraction interaction between said layer types, with said optic polarization efficiency being dependent on the number of reflection refraction interactions, so selected and optimized by the optic distance between layers, wherein said layers are positioned in a curved geometrical position allowing the spacing between said layers to be increased or decreased and allowing said layers to change the direction of channeled radiation, wherein at least one or more of said layers is formed of a material selected from the group consisting of air, liquid, gas and aero gel, wherein the spacing between said birefringent layers is geometrically positioned to approach a variable and minimum distance only supporting radiation reflection and refraction from said adjacent layer surfaces, wherein said high index layers are floating in the polarization conversion region, wherein an electromagnetic radiation collection micro-optic, comprising a reflective coating, is formed and positioned at the entrance aperture to act to collect, reflect, direct and concentrate the incoming radiation into the polarization conversion optic area, wherein a micro-optic, comprising an additional reflective coating, is formed and positioned at the exit aperture to reflect the channeled radiation out of the optic in a collimated or divergent state.