Patent ID: 7081584
Filing Date: 2006-07-25
Classification: H01L,H02S,Y02E

Abstract:
1. The method for deriving an electrical output from solar radiation, comprising the steps of: (a) providing a serially coupled multijunction photovoltaic cell having, a series connected array of junction unit cells with a stack orientation, a multijunction defined edge illumination receiving surface, said stack orientation being at a stack angle with respect to said receiving surface equivalent to Brewster's angle, an electrical output derivable at terminals and formed of impurity doped photovoltaic material exhibiting a given bandgap energy at a bandgap energy wavelength and a wavelength defined band of useful energy extending below said bandgap energy wavelength; (b) providing an imaging primary concentrator; (c) concentrating said solar radiation within a concentration light path with said imaging concentrator; (d) removing components of solar energy at said concentration light path, prior to the light impinging on said receiving surface, corresponding with at least a portion of those wavelengths above said bandgap energy wavelength; (e) providing a non-imaging internally reflecting secondary concentrator having a centrally disposed axis, an entrance of given dimensional extent located to receive said concentration light path, having an exit adjacent said receiving surface of dimensional extent less than said given dimensional extent and having an internally reflecting surface effective to homogenize light within said concentration light path while directing light in an impinging direction toward said cell edge illumination receiving surface effective to permit generation of said electrical output; and (f) coupling said terminals with a load.