Patent ID: 8884156

Claim:
A solar energy harvesting device comprising: a lightguide structure having opposing, locally parallel first and second boundary surfaces defining a peripheral edge extending between the first and second surfaces and comprising a material layer including a stimuli-responsive material (SRM) that is evenly distributed throughout the material layer, said material layer being disposed between the first and second boundary surfaces; means for concentrating solar radiation directed onto said device such that said solar radiation is concentrated at a focal point disposed inside the material layer; and a solar energy receiver disposed in a fixed relationship to said lightguide structure, wherein the SRM is characterized such that all of said SRM disposed in said material layer assumes a first state when a first amount of said concentrated solar radiation at said focal point is below a predetermined first level, and such that a portion of said SRM disposed in a focal zone adjacent to said focal point changes from the first state to a second state when said concentrated solar radiation at said focal point increases from said first amount to a predetermined second amount while a remaining portion of said SRM disposed outside of said focal zone remains in said first state, the second state being more opaque than the first state such that the concentrated solar radiation is redirected by said portion in said second state and transmitted through the remaining portion of said SRM in said first state, wherein said solar energy receiver is positioned to receive at least a portion of said redirected concentrated solar radiation that is transmitted through the remaining portion of said SRM in said first state and exits the lightguide structure through said peripheral edge, wherein said lightguide structure further comprises a first transparent layer including said first surface and a second transparent layer including said second surface, said first and second transparent layers consisting of a solid light transparent material, wherein the material layer is disposed between said first transparent layer and said second transparent layer, wherein the material layer further comprises a mixture including a transparent carrier material comprising one of a gel material and a liquid, and wherein said SRM comprises a temperature dependent material having a lower critical solution temperature (LOST) in the range of 30° C. and 90° C.