Solar cells

A solar cell assembly comprising in combination

• a solar cell for generating an electrical current in response to electromagnetic radiation, said cell having a front surface and an electrode obscuring a plurality of regions of said front surface, said regions each having a characteristic dimension in a first direction and being spaced from one another along said first direction in a predetermined spatial frequency, said electrode comprising a comb-like array of equally spaced-apart parallel like conductors;
• a transparent front cover of predetermined refractive index having opposed first and second surfaces, both of said first and second surfaces confronting a medium having a refractive index different from said predetermined refractive index, said first and second surfaces having first and second contours respectively, each of said contours being in the form of a plurality of substantially identical cylindrical segments having a like plurality of substantially coplanar cylinder axes, adjacent ones of said cylinder axes being spaced apart a distance similar to that between adjacent ones of said conductors, each of said cylinder axes being disposed (a) in a plane substantially parallel to said conductors, (b) parallel to individual conductors, and (c) equidistant from an adjacent pair of said conductors, said cylinders being dimensioned and disposed so that selected rays of said radiation incident upon said cylinders are directed to regions of said front surface which are not obscured by said electrode;
• and
• means for securing said front cover to said cell in overlaying relation to said front surface so as to maintain said first and second surfaces at predetermined distances from said front surface.

A solar cell assembly comprising in combination

• a solar cell for generating an electrical current in response to electromagnetic radiation, said cell having a front surface and an electrode obscuring a plurality of regions of said front surface, said regions each having a characteristic dimension in a first direction and being spaced from one another along said first direction in a predetermined spatial frequency, said electrode comprising a comb-like array of equally spaced-apart parallel like conductors;
• a transparent front cover of predetermined refractive index having opposed first and second surfaces, said first surface confronting a medium having a refractive index different from said predetermined refractive index, said first surface having a contour, said contour having a spatial frequency along said first direction corresponding to the spatial frequency of said regions, said contour including a plurality of pairs of cylindrical segments, each segment having an axis substantially parallel to said conductors, each pair being disposed such that the segments intersect in a line substantially in opposing relationship to a one of said conductors, said cylindrical elements being dimensioned so that selected rays of said radiation incident near said lines are deflected through a predetermined angle and directed to regions of said front surface which are not obscured by said electrode;
• and
• means for securing said front cover to said cell in overlaying relation to said front surface so as to maintain said first surface at a predetermined distance from said electrode with said lines in a selected alignment with said regions, said predetermined distance being selected so that no less than one half of said characteristic dimension subtends said predetermined angle at said predetermined distance, and said alignment being selected to that said regions and zones are disposed along a path parallel to an incident ray of said radiation.

A solar cell assembly comprising in combination

• a solar cell for generating an electrical current in response to electromagnetic radiation, said cell having a front surface and an electrode obscuring a plurality of regions of said front surface, said regions each having a characteristic dimension in a first direction and being spaced from one another along said first direction in a predetermined spatial frequency, said electrode comprising a comb-like array of spaced-apart like conductors;
• a transparent front cover of predetermined refractive index having opposed first and second surfaces, said first surface at least in part confronting a medium having a refractive index different from said predetermined refractive index, said first surface having a contour comprising a plurality of spaced-apart identical prismatic sections, each of said sections being defined by a pair of intersecting lateral faces disposed to make equal but opposite angles, each greater than the critical angle, with a plane parallel said front surface, said pair of lateral faces intersecting along a line which is parallel to and centered opposite one of said conductors, said contour having a spatial frequency along said first direction corresponding to the spatial frequency of said regions, said lateral faces being dimensioned and disposed so that selected rays of said radiation incident upon said lateral faces are deflected through a predetermined angle and directed to regions of said front surface which are not obscured by said electrode, the projection of each of said prismatic sections on a plane parallel to said lines having a size along said first direction substantially the same size as said characteristic dimension, said first surface also including a plurality of planar sections parallel to said planar surface, each of said planar sections extending between a pair of said prismatic sections on a plane parallel to said lines, each said planar section having a size along said first direction substantially the same as the separation between adjacent said conductors, and said second surface being a substantially planar surface parallel to said lines and spaced apart from said first surface;
• and
• means securing said front cover to said cell in overlaying relation to said front surface with said first surface facing said front surface so as to maintain said first surface at a predetermined distance from said electrode with said prismatic sections in a selected alignment with said regions, said predetermined distance being selected so that no less than one half of said characteristic dimension subtends said predetermined angle at said predetermined distance, said alignment being selected so that said regions and zones are disposed along a path parallel to an incident ray of said radiation.