Luminescent Solar Concentrator With Distributed Outcoupling Structures And Microoptical Elements
AssigneePalo Alto Research Center Incorporated
InventorsPhilipp H. Schmaelzle, Robert A. Street
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Abstract
A luminescent solar concentrator including a light-guiding slab containing a luminescent material that generates light emissions in response to received sunlight, spaced-apart outcoupling structures that provide a distributed outcoupling of the light emissions through predetermined locations on one of the “broadside” (e.g., upper or lower) surfaces of the light-guiding slab, and optical elements positioned to redirect the outcoupled light emissions such that the light emissions are concentrated onto a predetermined target (e.g., a PV cell). Each optical element includes a collimating surface portion and optional returner surface.
Claims20
A solar concentrator for concentrating sunlight onto a solar receptor, the solar concentrator comprising:
- a light-guiding slab consisting of a light transparent material and having opposing parallel first and second broadside surfaces, and a luminescent material disposed in the light-guiding slab, the luminescent material being capable of absorbing sunlight having a first wavelength within a first wavelength range and generating light emissions having a second wavelength within a second wavelength range, the second wavelength of said light emissions being longer than the first wavelength, wherein said first and second broadside surfaces are formed and the light transparent material is selected such that, when sunlight enters the light-guiding slab and causes the luminescent material to produce said light emissions, at least some of the energy emissions are retained within the light-guiding slab by total internal reflection off of portions of the first and second broadside surfaces;
- a plurality of spaced-apart outcoupling structures, each said outcoupling structure being disposed on a corresponding outcoupling region of one of said first and second broadside surfaces, each outcoupling structure including a low-absorption, light scattering material disposed on said corresponding outcoupling region such that, when said retained light emissions are reflected onto said said corresponding outcoupling region, said retained light emission is redirected by said each outcoupling structure out of said light-guiding slab;
- and
- a plurality of optical elements fixedly secured to the light-guiding slab, each of the optical elements being arranged relative to an associated one of said plurality of outcoupling structures such that at least some of said light emissions passed out of said light-guiding slab by each said one of said plurality of outcoupling structures is directed into said associated optical element, wherein each of the optical elements is formed such that said light emissions are then redirected by said associated optical element in a predetermined direction toward said solar receptor.
A solar concentrator for concentrating sunlight onto a solar receptor, the solar concentrator comprising:
- a light-guiding slab consisting of a light transparent material and having opposing parallel first and second broadside surfaces, and a luminescent material disposed in the light-guiding slab, the luminescent material being capable of absorbing sunlight having a first wavelength within a first wavelength range and generating light emissions having a second wavelength within a second wavelength range, the second wavelength of said light emissions being longer than the first wavelength, wherein said first and second broadside surfaces are formed and the light transparent material is selected such that, when sunlight enters the light-guiding slab and causes the luminescent material to produce said light emissions, at least some of the energy emissions are retained within the light-guiding slab by total internal reflection off of portions of the first and second broadside surfaces;
- means for causing said light emissions retained within the light-guiding slab by total internal reflection and directed onto spaced-apart outcoupling regions of at least one of said first and second broadside surfaces to be passed out of said light-guiding slab;
- and
- a plurality of optical elements fixedly secured to the light-guiding slab, each of the optical elements being arranged relative to an associated one of said plurality of outcoupling regions such that at least some of said light emissions passed out of said light-guiding slab is directed into said plurality of optical elements, wherein the plurality of optical elements are formed such that said light emissions are then redirected by said plurality of optical elements in predetermined directions toward said solar receptor.
Dependencies are inferred from the claim text.