Patent US2248822A successfully refreshed from Google Patents.
US5153780A
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Method and apparatus for uniformly concentrating solar flux for photovoltaic applications
Assignee: United States, AS REPRESENTED BY OF ENERGY
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Filing: 1991-06-10
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Granted: 1992-10-06
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Expires: 2011-06-10
Abstract
Abstract A dish reflector and method for concentrating moderate solar flux uniformly on a target plane on a solar cell array, the dish having a stepped reflective surface that is characterized by a plurality of ring-like segments arranged about a common axis, and each segment having a concave spherical configuration.
Inventors
- 👤 Gary J. Jorgensen
- 👤 Meir Carasso
- 👤 Timothy J. Wendelin
- 👤 Allan A. Lewandowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:06
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/08; G02B5/10; F; F24; F24S; F24S23/00; F24S23/70; F24S23/80; H; H10; H10F; H10F77/00; H10F77/40; H10F77/42; H10F77/484; H10F77/488; Y; Y02; Y02E; Y02E10/00; Y02E10/40; Y02E10/50; Y02E10/52
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
86 words
A dish reflector for concentrating solar flux uniformly over a target plane on a solar cell array, said reflector comprising a plurality of concentric, concave, reflective surface elements, arranged symmetrically about a common axis which is perpendicular to said target plane, and each of said surface elements being defined with respect to its axial position forward of a parabolic reference dish sharing said common axis and having a vertex spaced from said target plane by a distance equal to the focal length of said reference dish.
Claim 2
Dependent Claim
86 words
A dish reflector for concentrating solar flux uniformly over a target plane on a solar cell array, said reflector comprising a plurality of concentric, concave, reflective surface elements, arranged symmetrically about a common axis which is perpendicular to said target plane, and each of said surface elements being defined with respect to its axial position forward of a parabolic reference dish sharing said common axis and having a vertex spaced from said target plane by a distance equal to the focal length of said reference dish.
Claim 3
Dependent Claim
27 words
A dish reflector as defined in claim 1 wherein each of said reflective surface elements comprises an equal fraction of the total reflective surface of said reflector.
Claim 4
Dependent Claim
18 words
A dish reflector as defined in claim 1 wherein said reflective surface elements are equal in surface area.
Claim 5
Dependent Claim
19 words
A dish reflector as defined in claim 3 wherein each of said reflective surface elements comprises a spherical segment.
Claim 6
Dependent Claim
25 words
A dish reflector as defined in claim 1 wherein each of said reflective surface elements is displaced from said reference dish by a predetermined amount.
Claim 7
Dependent Claim
31 words
A dish reflector as defined in claim 5 wherein each of said reflective surface elements has a curvature equal to 1/(2f) were f is the focal length of said reference dish.
Claim 8
Dependent Claim
17 words
A dish reflector as defined in claim 5 wherein each of said elements comprises a spherical configuration.
Claim 9
Dependent Claim
44 words
A dish reflector as defined in claim 5 wherein each of said reflective elements comprises a spherical segment and wherein the ratio of the focal length of said reference dish to the diameter of the aperture of said dish is equal to about 0.5.
Claim 10
Dependent Claim
19 words
A dish reflector as defined in claim 1 wherein each of said reflective surface elements comprises a spherical segment.
Claim 11
Dependent Claim
25 words
A dish reflector as defined in claim 9 wherein the solar concentration along said target plane is in the range of ±10% of 175 suns.
Claim 12
Dependent Claim
38 words
A dish reflector as defined in claim 1 wherein the curvature of each of said reflective surface elements is adapted to produce aberrations that spread out the solar image formed by said solar reflector on said target plane.
Claim 13
Dependent Claim
17 words
A dish reflector as defined in claim 11 wherein each of said elements comprises a spherical segment.
Claim 14
Dependent Claim
13 words
A dish reflector as defined in claim 11 comprising five said reflective elements.
Claim 15
Dependent Claim
16 words
A dish reflector as defined in claim 1 comprising three to five of said reflective elements.
Claim 16
Dependent Claim
28 words
A dish reflector as defined in claim 14 wherein each of said spherical reflective elements has a curvature equal to one-half the focal length of said reference dish.
Claim 17
Dependent Claim
13 words
A dish reflector as defined in claim 15 comprising five of said elements.
Claim 18
Dependent Claim
13 words
A dish reflector as defined in claim 1 comprising five said reflective elements.
Claim 19
Dependent Claim
23 words
A dish reflector as defined in claim 17 wherein said target plane is a circle of about 3.0 to 4.0 cm in diameter.
Claim 20
Dependent Claim
32 words
A dish reflector as defined in claim 1 wherein each of said reflective elements has a degraded surface with specularity errors that tend to spread the flux reflected from each said element.
Claim 21
Dependent Claim
18 words
A dish reflector as defined in claim 19 wherein said uniform flux is range of about 175 suns.
Claim 22
Dependent Claim
18 words
A dish reflector as defined in claim 19 wherein the specularity of said reflector is about 3.0 mrad.
Claim 23
Dependent Claim
30 words
A dish reflector as defined in claim 1 wherein each of said reflective elements has a spherical configuration adapted to provide optical aberrations that spread out over said target plane.
Claim 24
Dependent Claim
27 words
A dish reflector as defined in claim 1 wherein the specularity of each of said reflective elements is in the range of about 1.5 to 3.0 mrad.
Claim 25
Dependent Claim
18 words
A dish reflector as defined in claim 1 wherein ech of said reflective elements has a parabolic configuration.
Claim 26
Dependent Claim
37 words
A dish reflector as defined in claim 1 wherein the vertices of each of said elements are displaced from the vertex of said reference dish be a predetermined distance from said reference dish along said common axis.
Claim 27
Independent Claim
141 words
A method for concentrating solar flux to moderate levels of concentration, in the range of 75 to 400 suns, uniformly over a target plane on a solar cell array, including the steps of: a) providing a dish reflector comprising a plurality of concentric, concave, reflective surface elements, arranged symmetrically about a common axis, and each of said surface elements being defined with respect to its axial position forward of a parabolic reference dish sharing said common axis; b) positioning said reflector relative to said target plane such that said common axis is perpendicular to said target plane and such that the vertex of said parabolic reference dish is spaced from said target plane by a distance equal to the focal length of said reference dish; and c) receiving said solar flux and reflecting it from said reflector onto said target plane.
Claim 28
Independent Claim
141 words
A method for concentrating solar flux to moderate levels of concentration, in the range of 75 to 400 suns, uniformly over a target plane on a solar cell array, including the steps of: a) providing a dish reflector comprising a plurality of concentric, concave, reflective surface elements, arranged symmetrically about a common axis, and each of said surface elements being defined with respect to its axial position forward of a parabolic reference dish sharing said common axis; b) positioning said reflector relative to said target plane such that said common axis is perpendicular to said target plane and such that the vertex of said parabolic reference dish is spaced from said target plane by a distance equal to the focal length of said reference dish; and c) receiving said solar flux and reflecting it from said reflector onto said target plane.
Claim 29
Dependent Claim
19 words
A method as defined in claim 26 for concentrating solar flux in the range of 75 to 200 suns.
Claim 30
Dependent Claim
21 words
A method as defined in claim 27 wherein each of said reflective surface elements is essentially equal in effective surface area.
Claim 31
Dependent Claim
14 words
A method as defined in claim 26 wherein said reflective elements comprise spherical segments.
Claim 32
Dependent Claim
29 words
A method as defined in claim 26 wherein each of said reflective elements has a curvature equal to 1/(2f), where f is the focal length of said reference dish.
Claim 33
Dependent Claim
30 words
A method as defined in claim 26 including the step of degrading said reflective surface elements to increase the specularity error of said reflective surface elements in a predetermined manner.
Claim 34
Dependent Claim
27 words
A method as defined in claim 31 wherein said reflective elements are degraded so as to have specularity error in the range of 5.0 to 10.0 mrad.
Claim 35
Dependent Claim
23 words
A method as defined in claim 31 wherein the number of said reflective elements present is in the range of three to five.
Claim 36
Dependent Claim
35 words
A method as defined in claim 31 including the step of intimately covering said surface elements with a thin layer of reflective material whereby said thin layer takes on the surface characteristics of said elements.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-10-06 | 1996-04-06 | 1996-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-10-06 | 2000-04-06 | 2000-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-10-06 | 2004-04-06 | 2004-10-06 | $7700.00 | Window Closed / Lapsed |