# US 10,872,988 B1 · Photovoltaic device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,872,988 B1 - Document ID: US10872988B1 - Status: Granted - Kind: B1 - Application number: 14/170,007 - Filed: 2014-01-31 - Granted: 2020-12-22 - Earliest claimed: 2013-02-03 - Applicants: Mark R. Schroeder; Kenneth Buciak - Inventors: Mark R. Schroeder; Kenneth Buciak - Web page: https://patentgrep.com/patent/US10872988B1 ## CPC - H10F 77/147: {Shapes of bodies} - H10F 19/00: Integrated devices, or assemblies of multiple devices, comprising at least one photovoltaic cell covered by group H10F10/00, e.g. photovoltaic modules - H10F 77/122: comprising only Group IV materials - H10F 77/148: {Shapes of potential barriers} - H10F 77/169: Thin semiconductor films on metallic or insulating substrates - H10F 77/315: {the coatings being antireflective or having enhancing optical properties} - H10F 77/484: {Refractive light-concentrating means, e.g. lenses} - H10F 77/703: {of the semiconductor bodies, e.g. textured active layers} - Y02E 10/52: PV systems with concentrators - Y02E 10/547: Monocrystalline silicon PV cells - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract Briefly, in accordance with one or more embodiments, photovoltaic device comprises a core having a shape that is at least partially spherical, an absorber disposed over the core, and a transparent conductor disposed over the absorber. ## Claims ### Claim 1 A photovoltaic device, comprising: a core having a shape that is at least partially spherical; an absorber disposed over the core and having a shape that is at least partially curved; and a transparent conductor disposed over the absorber and having a shape that is at least partially curved; wherein the transparent conductor has an index of refraction that is less than an index of refraction of the absorber such that the transparent conductor and the absorber function as a lens to refract impinging photons into the absorber; wherein an interface between the transparent conductor and the absorber has a smoothness defined such that a distance between peak to peak features on a surface of the transparent conductor at the interface is less than about one tenth of a wavelength of the impinging photons divided by the index of refraction of the transparent conductor; and wherein the absorber and the transparent conductor have indices of refraction and thicknesses selected to function as an annular waveguide such that the photons impinging into the absorber travel circumferentially in the absorber about a center of the core. ### Claim 2 (depends on 1) A photovoltaic device as claimed in claim 1, wherein the absorber provides a greater homogeneity of photon density of states in a direction perpendicular to an interface between the core and the absorber than in an absorber of a planar photovoltaic device in response to incoming light. ### Claim 3 (depends on 1) A photovoltaic device as claimed in claim 1, wherein the absorber comprises a first semiconductor layer of a first type and a second semiconductor layer of a second type. ### Claim 4 (depends on 1) A photovoltaic device as claimed in claim 1, wherein the absorber comprises a first semiconductor layer of a first type, a second semiconductor layer of a second type, or an intrinsic layer disposed between the first semiconductor layer and the second semiconductor layer, or combinations thereof. ### Claim 5 (depends on 1) A photovoltaic device as claimed in claim 1, wherein the core comprises monocrystalline silicon. ### Claim 6 (depends on 1) A photovoltaic device as claimed in claim 1, wherein the transparent conductor comprises a transparent conductive oxide. ### Claim 7 (depends on 1) A photovoltaic device as claimed in claim 1, wherein the core is at least partially formed on a substrate. ### Claim 8 (depends on 1) A photovoltaic device as claimed in claim 1, wherein the core is at least partially formed on a substrate, and further comprising a back contact layer disposed between the core and the substrate. ### Claim 9 (depends on 1) A photovoltaic device as claimed in claim 1, wherein the core has structure comprising at least a partial sphere, at least a partial spheroid, or at least a partial pseudo-sphere, or combinations thereof. ### Claim 10 A solar power system, comprising: an array of photovoltaic devices; wherein the photovoltaic devices comprise: a core having a shape that is at least partially spheroidal; an absorber disposed over the core and having a shape that is at least partially curved; and a transparent conductor disposed over the absorber and having a shape that is at least partially curved; wherein the transparent conductor has an index of refraction that is less than an index of refraction of the absorber such that the transparent conductor and the absorber function as a lens to refract photons into the absorber; wherein an interface between the transparent conductor and the absorber has a smoothness defined such that a distance between peak to peak features on a surface of the transparent conductor at the interface is less than about one tenth of a wavelength of the impinging photons divided by the index of refraction of the transparent conductor; and wherein the absorber and the transparent conductor have indices of refraction and thicknesses selected to function as an annular waveguide such that the photons impinging into the absorber travel circumferentially in the absorber about a center of the core. ### Claim 11 (depends on 10) A solar power system as claimed in claim 10, wherein the photovoltaic devices are arranged at coordinates wherein the photovoltaic devices are not shadowing each other over a widest or a nearly widest range of incident angles of light rays from a light source. ### Claim 12 (depends on 10) A solar power system as claimed in claim 10, wherein the absorber comprises a first semiconductor layer of a first type, a second semiconductor layer of a second type, or an intrinsic layer disposed between the first semiconductor layer and the second semiconductor layer, or combinations thereof. ### Claim 13 (depends on 10) A solar power system as claimed in claim 10, wherein the core comprises monocrystalline silicon. ### Claim 14 (depends on 10) A solar power system as claimed in claim 10, wherein the transparent conductor comprises a transparent conductive oxide. ### Claim 15 (depends on 10) A solar power system as claimed in claim 10, wherein the core is at least partially formed on a substrate. ### Claim 16 (depends on 10) A solar power system as claimed in claim 10, wherein the core is at least partially formed on a substrate, and further comprising a back contact layer disposed between the core and the substrate. ### Claim 17 (depends on 10) A solar power system as claimed in claim 10, wherein the core has structure comprising at least a partial sphere, at least a partial spheroid, or at least a partial pseudo-sphere, or combinations thereof. ### Claim 18 (depends on 10) A solar power system as claimed in claim 10, wherein the photovoltaic devices are arranged in a regular pattern, in an irregular pattern, in a hexagonal pattern, or in a trigonal pattern.