1. Technical Field
The disclosure relates generally to lenses, and more particularly to a lens for condensing the solar light.
2. Description of the Related Art
Generally, solar light is considered to be aligned. A standard Fresnel lens is configured for concentrating solar light for a solar cell. However, the intensity of light through the Fresnel lens is not uniform. When the solar light passes through the Fresnel lens, the intensity of the center is normally higher than that of periphery. Thus, what is called for is a lens that can overcome the limitations described.
Referring to
The transparent member 11 is circular. The transparent member 11 includes a first surface 110 and a second surface 112. The second surface 112 is configured for receiving the solar light. The first surface 110 and the second surface 112 are planar. The transparent member 11 is made of resin or glass.
The conical protrusion 12 is defined at a center 114 of the first surface 110. The annular protrusions 13 are concentrically defined on the first surface 110 and configured around the conical protrusion 12. Each of cross-sections along the line II-II of the protrusions 13 approximately forms a right-angled triangle at a side of the center 114 of the first surface 110 of the transparent member 11. Each of the triangles includes a bottom surface 130, a first surface 132 which is perpendicular to the bottom surface 130, a second surface 134 which is slantwise to the bottom surface 130, a first angle θ and a second angle α and a third angle γ. The bottom surfaces 130 of the triangles are on the first surface 110. The second surfaces 132 are located toward the conical protrusion 12. The radius of the conical protrusion 12 and the widths of the bottom surfaces 130 increase in turn outwards from the center 114. The second angles α increase in turn outwards from the conical protrusion 12. In the first embodiment, a relation among the radius of the conical protrusion 12 and the widths of the bottom surfaces 130 outwards from the center 114 of the transparent member 11 provide an increasing arithmetical progression.
A cross section of the conical protrusion 12 could be considered as consisting of two right-angled triangles beside the center 114. A width of a bottom surface of each of the triangles defined by the conical protrusion 12 equals to the radius of the conical protrusion 12. The radius of the conical protrusion 12 is less than any of the widths of the bottom surfaces 130.
The transparent member 11 can be triangular or elliptical, there being no limitation to the shape as disclosed.
Referring to
Referring to
Referring to
Referring to
R1 is the radius of the transparent member 11. R2 is the radius of the solar cell plate 21. D is a distance between the solar cell plate 21 and the first surface 110 of the transparent member 11. mmax is total number of the triangles at a side of the transparent member 11 relative to the center 114, which in the embodiment of
Uniform intensity can be easily obtained utilizing the non-imaging lens 10 satisfying the formulae (1) and (2).
While the disclosure has been described by way of example and in terms of exemplary embodiment, it is to be understood that the disclosure is not limited thereto. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
Number | Date | Country | Kind |
---|---|---|---|
200910307046.7 | Sep 2009 | CN | national |
This application is related to patent application Ser. No. ______, entitled “LENS WITH A DETERMINED PITCH” and filed on ______, 2010 (Attorney Docket No. US26737) and patent application Ser. No. ______, entitled “LENS WITH MULTIPLE PROTRUSIONS” and field on ______, 2010 (Attorney Docket No. US26739). Such applications have the same inventors and assignee as the present application.